# AC 33-9: Developing Data for Major Repairs of Turbine Engine Parts - Type: Advisory circular (guidance, not mandatory unless a rule or AD requires it) - Status: Current - Approved: April 30, 2010 - Last reviewed: September 27, 2018 - Family: AC 33-9 - 14 CFR parts: 33, 34, 43 - Pages: 176 - PDF: https://openairdocs.org/files/sha256/84/48/8448fc06f79a882691050f6eb029ac384c0a4bc5eab1f29932e9e61a14945ddd - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/31916B17FF7305D48625771C006F2ECA.0001 - DRS record last changed: November 21, 2025 - Page: https://openairdocs.org/ac/33-9 ## Versions - [AC 33-9](https://openairdocs.org/ac/33-9) (Current), approved Apr 30, 2010, 176 pages ## Text Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 U.S. Department of Transportation Federal Aviation Administration Advisory Circular Subject: Developing Data for Major Repairs of Turbine Engine Parts Date: 4/30/10 Initiated by: ANE-110 AC No: 33-9 1. Purpose. a. This advisory circular (AC) provides information and guidance on developing the technical data needed for major repairs of critical and complex turbine engine parts. This guidance will help persons developing major repair data meet the requirements of Title 14 of the Code of Federal Regulations (14 CFR) part 43 to restore the engine to at least equal to its original or properly altered condition. This does not mean that a repaired part must be returned to a factory-new condition. However, the engine on which the repaired part is installed must remain airworthy and in compliance with the applicable regulations. For repairs of turbine engines and parts, the applicable requirements are Airworthiness Standards: Aircraft Engines (14 CFR part 33) and Fuel Venting and Exhaust Emissions Requirements for Turbine Engine Powered Airplanes (14 CFR part 34). b. Additionally, this AC provides guidance to assist persons developing major repairs with developing a continued operational safety plan. It also helps them evaluate engine parts recovered from accidents and incidents prior to making a repair. 2. Applicability. a. This AC provides guidance to all persons developing the technical data to substantiate major repairs for critical or complex turbine engine parts, including type certificate (TC) and supplemental type certificate (STC) holders. b. This guidance is neither mandatory nor regulatory in nature and does not constitute a regulation. It describes acceptable means, but not the only means, for demonstrating compliance with the applicable regulations. The FAA (“we”) will consider other methods of demonstrating compliance that a person developing repair data may elect to present. Terms such as “should,” “shall,” “may,” and “must” are used only in the sense of ensuring applicability of this particular method of compliance when the acceptable method of compliance in this document is used. While these guidelines are not mandatory, they are derived from extensive FAA and industry experience in determining compliance with the applicable regulations. On the other hand, if we become aware of circumstances that convince us that following this AC would not result in ### Page 2 2 compliance with the applicable regulations, we will not be bound by the terms of this AC, and we may require additional substantiation as the basis for finding compliance. c. This document does not change, create any additional, authorize changes in, or permit deviations from, existing regulatory requirements. 3. Related References. Please check the FAA’s website at http://www.faa.gov/regulations_policies/ for the latest revision of the following documents. a. AC 20-62D, Eligibility, Quality, and Identification of Aeronautical Replacement Parts; May 24, 1996. b. AC 33.75-1A, Guidance Material for 14 CFR 33.75, Safety Analysis; September 26, 2007. c. AC 39-8, Continued Airworthiness Assessments of Powerplant and Auxiliary Power Unit Installations of Transport Category Airplanes; September 8, 2003. d. AC 43-18, Fabrication of Aircraft Parts by Maintenance Personnel; March 24, 2006. e. AC 120-77, Maintenance and Alteration Data; October 7, 2002. f. Order 8110.37D, Designated Engineering Representative (DER) Handbook; August 10, 2006. g. Order 8110.4C, Type Certification; August 14, 2008. h. Order 8110.54, Instructions for Continued Airworthiness Responsibilities, Requirements, and Contents; July 1, 2005. i. Order 8120.2F, Production Approval and Certificate Management Procedures; January 30, 2009. j. FAA Order 8120.11, Disposition of Scrap or Salvageable Aircraft Parts and Materials; February 12, 1996. 4. Background. a. The designs of many critical and complex turbine engine parts, hereafter referred to as “parts,” require the use of advanced design and test methodologies, comprehensive materials data, and refined manufacturing techniques to achieve high levels of safety, reliability and performance. A person developing a repair for a critical or complex part should have a thorough understanding of the part’s design characteristics, operational environments, operating requirements, and failure modes and effects. This knowledge is useful for determining if a repair to a part is major and for developing the appropriate technical data for FAA approval. ### Page 3 b. Our previous evaluations of major repair data packages for critical and complex parts have indicated that the data were not always adequate to support substantiation of the repair. Data developed for major repairs of critical or complex parts may typically include rigorous analyses and tests to show the engine on which the repaired part is installed will be at least equal to its original or properly altered condition. An original or properly altered condition is an airworthy condition that existed before the need for the proposed repair. An airworthy condition means the aircraft conforms to its type certificate and is in a condition for safe operation. c. This AC uses part categorization as an aid for persons to determine whether a part being repaired is a critical or complex part. In addition, this AC recommends certain information be included in major repair data packages to improve consistency and completeness. In Appendix 2 of this AC, we also provide templates for repairs related to various engine part families to assist repair developers in identifying the technical elements and regulatory requirements when developing and substantiating similar repairs, if determined major. 5. Part Categorization. This AC categorizes parts based on their most severe potential failure effect using various methods for assessing malfunctions and failure modes. To assess malfunctions and failure modes, repair developers may use the failure modes and effects assessment described in Appendix 1 of this AC or other acceptable analytic techniques. Refer to AC 33.75-1A for examples of other acceptable techniques. a. Part Categories. The categories used in this AC are consistent with categories found in Order 8120.2 and AC 39-8, and used in AC 43-18. The part categories are: (1) Category 1. A product, i.e. engine, or part(s) thereof, whose failure could prevent continued safe flight and landing; resulting consequences could reduce safety margins, degrade performance, or cause loss of capability to conduct certain flight operations. A Category 1 part, for the purpose of this AC and Orders 8110.37 and 8110.4, is a critical part. (2) Category 2. An engine or part(s) thereof whose failure would not prevent continued safe flight and landing; resulting consequences may reduce the capability of the aircraft or the ability of the crew to cope with adverse operating conditions or subsequent failures. For the purpose of this AC and Order 8110.4, a Category 2 part is typically a complex part that may affect a critical part. (3) Category 3. An engine or part(s) thereof whose failure would have no effect on continued safe flight and landing of the aircraft. The only consequence would be partial or complete loss of engine thrust or power (and associated engine services). For single engine applications, consider changing part categorization to Category 1 or 2 if complete loss of thrust could prevent continued safe flight and landing or reduce the ability of the crew to cope with adverse operating conditions or subsequent failures. b. Tables of Potential Failure Effects. The following tables provide some potential failure effects for Categories 1 and 2. We also listed a few examples of parts whose malfunction or failure could result in one or more of the listed potential failure effects. ### Page 4 4 Table 1. Category 1 Engine Parts Potential Failure Effects Part Examples (1) Non-containment of highenergy debris. (2) Concentration of toxic products in the engine bleed air intended for the cabin, and sufficient to incapacitate crew or passengers. (3) Significant thrust in the opposite direction to that commanded by the pilot. (4) Uncontrolled fire. (5) Failure of the engine mount system leading to inadvertent engine separation. (6) Release of the propeller by the engine, if applicable. (7) Complete inability to shut the engine down. Life-limited parts Main engine mounts, with no redundant load carrying features High pressure vessels (for example, casings subject to compressor discharge pressure and combustor pressure) Containment structures Fan blades Fuel system shut-off Primary structures (for example, structures that provide support and rigidity of the main engine backbone and for attachment of engine to airframe) Thrust reverser control component if thrust reverser control component is part of the engine type certificate. ### Page 5 5 Table 2. Category 2 Engine Parts Potential Failure Effects Part Examples (1) Controlled fires (that is, those brought under control by shutting down the engine or by onboard extinguishing systems). (2) Case burn-through where it can be shown there is no propagation to hazardous engine effects. (3) Release of low-energy parts where it can be shown there is no propagation to hazardous engine effects. (4) Vibration levels that result in crew discomfort. (5) Concentration of toxic products in the engine bleed air for the cabin sufficient to degrade crew performance. (6) Thrust in the opposite direction to that commanded by the pilot, below the level defined as hazardous. (7) Loss of integrity of the load path of the engine supporting system without actual engine separation. (8) Generation of thrust greater than maximum rated thrust. (9) Significant uncontrollable thrust oscillation. (10) Loss of protection such as loss of overspeed protection or loss of containment case capability. (11) Effect or influence on a Category 1 part. Rotating parts that are not life-limited (for example, compressor and turbine airfoils) Accessory gearbox and internal components Engine bearings Spinners Main engine mounts with redundant load carrying features Static gas path parts (for example, vanes and seals) Control system actuators Combustion liners Fuel nozzles ### Page 6 6. Developing Data for Major Repairs. To improve the quality and adequacy of data for major repairs of critical (Category 1) and complex (Category 2) parts, we recommend persons developing the major repair data include the following information in their repair data packages: a. A description of: (1) The part to be repaired, including the part number. (2) The repair, including any associated limitations. For example: • The extent of the damage the repair covers. • How many times, if limited, the repair can be repeated on a single part. b. The part categorization, if categorization is used. c. The applicable sections of the regulatory requirements from the certification basis for the engine(s) that the repaired part is eligible for installation on. d. An applicability assessment of any related service difficulty reports and airworthiness directives (ADs) to the part. e. The complete step-by-step “how to” instructions for accomplishing the repair. This should include drawings and specifications, new materials and fabrication details, if any. f. Technical data. The regulations require that when performing a major repair, the work be done in accordance with technical data approved by the Administrator. Technical data also includes substantiation data to show compliance to applicable regulatory requirements. (1) Category 1 parts. We recommend that persons developing data in support of a major repair of a Category 1 part meet with the project aircraft certification office (PACO) to develop a substantiation plan before submitting a data package. The plan should outline the pertinent technical and regulatory requirements and testing, as needed to develop the data and substantiate the repair. In addition, the plan should identify process controls, inspections or tests, or both, required in the step-by-step procedures to mitigate the risks of improperly completing the repair. Note: For major repairs of Category 1 parts, Order 8110.37, Designated Engineering Representative (DER) Handbook, requires DERs notify the PACO prior to approval of the data. Order 8110.4, Type Certification, requires PACO engineers notify the accountable directorate of a major repair of a Category 1 part and coordinate data approval with the certificate management ACO. (2) Category 2 parts. We recommend persons developing data in support of a major repair of a Category 2 part use the templates in Appendix 2 of this AC or develop a new template, if applicable. ### Page 7 (a) Together with industry we developed the sample templates in Appendix 2 for typical repairs that were previously determined major. These templates may be used as aids to identify technical elements and regulatory requirements to be considered when developing your data and substantiating your repair for similar repairs to Category 2 parts, if determined major. These templates are not all inclusive; rather, they are for a limited number of typical Category 2 parts. (b) Persons using these templates should discuss any questions with the PACO. If a template is not available for a proposed major repair, consider developing a new template. Using a format consistent with the templates provided will help ensure that your template identifies the applicable technical considerations and regulatory requirements. You should review the new template with the PACO early in the project to determine if any additional data will be needed. g. An assessment of the applicability of the Instructions for Continued Airworthiness (ICAs). If ICAs are affected or needed, supplemental ICAs must be provided. Refer to FAA Order 8110.54, Instruction for Continued Airworthiness Responsibilities, Requirements, and Contents, for further information. 7. Developing a Continued Operational Safety (COS) Plan. a. COS Management Plan. Repair approval holders and persons making a major repair must perform their work in accordance with approved technical data and applicable performance regulations. If service experience or FAA oversight audits show the repair data was inadequate, in error, or the work was performed improperly, the FAA will evaluate the safety impact and take appropriate action. That action may be to issue an AD, Special Airworthiness Information Bulletin (SAIB), or other appropriate document. In such a case, the repair approval holder or the person who performed the work, or both, may be requested to develop a corrective action program or a design change to restore safety to an acceptable level. Therefore, the FAA recommends that repair approval holders who develop data for major repairs and persons who use that data to perform maintenance develop a COS management plan. b. Part Identification. To facilitate part tracking as part of a COS management plan, we recommend that persons proposing a repair provide supplementary part identification procedures. (1) Any original part markings, such as the part number and serial number, should be maintained. Supplementary identification should be permanent and legible. It should include a name, trademark, or other symbol of the person performing the repair. Supplementary identification combined with adequate maintenance records ensures that if a problem occurs the affected parts can be identified, tracked, and, if necessary, removed from service. (2) Parts subject to an airworthiness limitation should retain their original markings in accordance with § 45.14. When adding supplementary identification to the part, repair developers must ensure that their repair identification does not adversely impact the part. For example, do not apply repair identification on contact surfaces or near radii of parts because ### Page 8 8 these are typically areas of high stress concentrations. When impractical, i.e., the part is too small or applying the repair identification would compromise part integrity, we recommend entering part identification information in the part’s maintenance records. c. Maintaining Records. Federal Aviation Regulations have specific minimum time requirements for the retention of certain maintenance records. Experience has shown that the maintenance records and the availability of repair data can be extremely valuable for accident investigation and corrective action development. Therefore, we recommend that the data approval holder and persons performing the major repairs, for example, repair stations, owner/operators, or air carriers, keep records that include at least the following: (1) A record keeping plan to: (a) Identify where repaired parts are in service or who the customer owners/operators of the parts are. (b) Retain records of the work performed during the repair. (c) Retain the technical data for the parts. (2) Documentation of the quality control of the repair. (3) A means to monitor the performance of repaired parts in service. (4) A means to identify and isolate parts that do not conform to approved data or are unairworthy. (5) The capability to analyze failed parts and identify root causes of failures in order to develop and implement corrective action(s) when needed. 8. Repair of Engine Parts Recovered from Accidents or Incidents. a. We recommend persons repairing parts recovered from accidents or incidents inspect these parts for hidden damage prior to beginning a repair. Repair stations are required to perform this inspection per regulation, refer to § 145.211(c). This pre-repair inspection will ensure the part does not have hidden damage or has not been overstressed or overheated, which is not always obvious from visual or dimensional inspection. b. The ICAs may be insufficient for this pre-repair inspection. Therefore, developing special instructions for evaluating repairability of such parts may be appropriate. We suggest repair developers review the part’s maintenance and operational records for relevant service information and verify the history and origin of the parts when making that determination. Parts that are determined to be unsuitable for repair should not be repaired and should be returned to the owner with the appropriate entry in the part maintenance record. Refer to AC 20-62 and Order 8120.11 for further information on the airworthiness and eligibility of such parts. Parts ### Page 9 9 otherwise eligible for repair which do not exhibit evidence of irreparable damage may be repaired. Francis A. Favara Manager, Engine and Propeller Directorate Aircraft Certification Service ### Page 10 Appendix 1 10 APPENDIX 1. FAILURE MODES AND EFFECTS ASSESSMENT 1. A failure modes and effects assessment is a qualitative process, independent of failure rates and probabilities, by which each failure mode of a part in the engine system is analyzed. Some top-level functions typically considered in an engine failure modes and effects assessment are:  Maintaining structural integrity, including allowed overspeed and overtemperature exceedances;  Providing thrust or power;  Operating in inclement weather;  Providing customer bleed, power extraction, or both; and  Meeting fuel consumption, exhaust gas temperature, vibration, emission or noise limits. 2. Each system and subsystem of the engine is broken down into its basic functions using a functional block diagram consistent with the Air Transport Association policy for identification and definition of systems. 3. The functional block diagram defines each system and subsystem, and all their functions, in the turbine engine. The experienced safety engineer performing the analysis determines the partto-part and part-to-system influences in both directions (input and output). The process flow is shown in figure A1.1 below: Figure A1.1. Process Flow Diagram Determine input functions from other engine systems Identify parts within the system being analyzed Determine functions provided by the part being analyzed Determine consequence of failure to provide the desired function by design intent Determine outcome on part, engine system, and the engine Categorize part by outcomes in Tables 1 and 2 of this AC ### Page 11 Appendix 1 11 4. The part categorization process is built around the fundamental understanding of the part function and its potential effects on physically or functionally mating parts or both. The fundamental premise in the categorization process, and in the physical operation and function of the turbine engine, is system interactions. a. System interactions are influences a part, or a set of parts, can have on the turbine engine, propulsion system, or aircraft through form, fit, or function, where (1) Form is the shape, size, dimensions, and other physical measurable parameters that uniquely characterize a part. (2) Fit is the ability of a part to interface or interconnect, physically and functionally, at the common boundaries with another part or system of the engine. (3) Function is the action(s) the part is designed to perform in the engine. b. These influences may extend beyond the component being classified, may be direct or indirect, and may develop immediately or over time. Characteristics of these influences include: (1) Direct influences, which are form and fit. These influences are based on physical contact or interface clearances between adjacent parts. (2) Indirect influences, which are functional in nature. These influences are not based on physical contact, but may be aerodynamic, thermal, or vibratory. 5. The interactions where the consequence of failure is the furthest from the cause are the most difficult to identify. Many fundamental relationships in part interactions and subsequent system effects exist. Figure A1.2 below provides four examples. ### Page 12 Appendix 1 12 Figure A1.2. Part Interaction Considerations Part Interaction Considerations •Fluid interactions • Air, fuel, oil •Direct interactions • Mechanical loading • Aero loading • Contact/wear • Chemical •Indirect interactions • Vibration • Acoustical • Primary air • Secondary air • Control system • Structural dynamics • Sensor systems Stage 1 HPT Nozzle 1 2 3 4 Effective area/flow HPC press. ratio Stall margin consumption Stall at limiting condition Fuel Pump Impeller Fuel flow schedule Fuel to Combustor Starting characteristic Altitude re-light capability Stage 2 HPT Nozzle Cooling flow to rotor Purge flow level Hot gas ingestion Critical part temperature & life Rotor Blade Loads and moments on disk Local dovetail loading Dovetail or slot bottom life LLP life impact Indirect Effect Indirect Effect Time Relationship Direct Effect ### Page 13 Appendix 2 13 APPENDIX 2. SAMPLE TEMPLATES 1. Purpose. This appendix includes templates for major repairs related to 17 engine part families, listed in Table A2-1 below. The FAA selected them based on typical repairs for complex turbine engine parts submitted as major. These templates will aid repair developers in identifying the technical elements and regulatory requirements they should consider when developing and substantiating similar major repairs. Persons developing data must ensure that any additional technical criteria or regulatory requirements are met for their specific proposed major repair. 2. Template Instructions. Each template shows both shaded and un-shaded (clear) cells corresponding to the sample repair and its specific engineering, technical and regulatory considerations. Those cells that are generally applicable are un-shaded. However, the repair developer must decide if the cells need to be completed or not. The templates identify the current part 33 regulations, Amendments 1-20 inclusive, applicable to turbine engines as an example. When reviewing the associated regulatory considerations, the repair developer should determine applicability and identify the corresponding methods of compliance to be used to provide the supporting data. a. The certification basis of the engine(s) on which the repaired part is eligible for installation identifies the regulatory requirements that should be reviewed for applicability. Applicable regulations are those regulations that must be evaluated to determine that the engine remains in compliance and airworthy with respect to the repair work performed. For critical and complex parts, the repair developer should determine which of the original compliance findings to those applicable regulations could be affected by their proposed major repair. To do this, you must understand how the part to be repaired functions in the engine operating environment, and the associated regulatory requirements. Repair developers substantiate their repair to these requirements, using acceptable methods, to show that the condition of the engine on which the repaired part is installed will be at least equal to its original or properly altered condition. b. Acceptable methods are identified as follows: (1) D - Documentation (for example, Instructions for Continued Airworthiness). (2) A - Analysis of relevant data. (3) I - Inspection (for example, metallurgical examination, hardness testing, Nondestructive testing inspection). (4) R - Rig testing. (5) C - Component testing. (6) E - Engine testing. ### Page 14 Appendix 2 14 (7) S - Similarity to previously FAA approved data. Repair developers will need to show that the previously approved data is applicable to the new proposed repair, and to the product type design if different than the type design for which the data was previously approved. 3. Sample Templates. If a template is not available for a particular major repair, the repair developer can create or modify another as necessary. Table A2-1. Sample Templates. Template Number Title Page 1 Bearing Compartment and Carbon Seal Parts Family 15 2 High Pressure Turbine (HPT) Blade Part Family 25 3 Low Pressure Compressor (LPC) – High Pressure Compressor (HPC) Blade Part Family 36 4 Blades – Low Pressure Turbine (LPT) 46 5 Combustor Part Family 55 6 Externals Part Family (Tubes, Manifolds, Ducts, Brackets) 66 7 Fuel Nozzle Part Family 75 8 Gearbox Housing Assembly Part Family (Shafts, Gears, Housings) 84 9 Low Pressure Compressor (LPC) – High Pressure Compressor (HPC) Stator Part Family – Vane Sector (And Full Ring) Type Stators 94 10 Low Pressure Compressor (LPC) – High Presser Compressor (HPC) Stator Part Family – Fixed Vane Type Stators 103 11 Major Engine Cases 112 12 Major Rotating (Non-Life Limited) Part Family (Excluding Turbine Shaft Coupling Part Family) 121 13 High Pressure Compressor (HPC)/High Pressure Turbine (HPT)/Low Pressure Turbine (LPT) Airseals (Non-Rotating) And Shrouds (Stationary) Part Family 130 14 Static Structure Part Family (ducts, bearing housings, etc.) 138 15 Low Pressure Compressor (LPC) – High Pressure Compressor (HPC) Stator Part Family – Variable Vane Type Stators 148 16 HPT Vane Part Family 157 ### Page 15 Appendix 2 15 17 Low Pressure Turbine (LPT) Vane Part Family 166 ### Page 16 Appendix 2 16 Template 1 **REPAIR SUBSTANTIATION CHECKLIST - BEARING COMPARTMENT AND** **CARBON SEAL PART FAMILIES** Categories of Bearing Compartment & Carbon Seal Part Family Repair. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES OF** **REPAIRS** **REPAIR DESCRIPTION** 1. Restoration of Protective Coating  This repair includes touch-up coating 2. Weld or Braze Repair  This repair excludes detail part replacement 3. Weld or Braze Repair  This repair includes detail part replacement 4. Assembly and/or Disassembly  This repair assembles, disassembles, removes and replaces detail parts, or s ubassemblies without use of permanent attachment techniques (i.e.; welding or brazing). Assembly is either bolted or riveted. 5. Blend Repair 6. Dimensional Restoration by Coating or Plating 7. Bushing/Helicoil Repair 8. Straightening, Re-twist, or Reforming Repair  This repair includes straightening of bent knife edges 9. Surface Treatment Repair  This repair includes peening, vibratory tumble (e.g.; restoration of surface finish/texture) 10. Machining Repair  This repair includes lapping, skim cut, non-conventional machining. 11. Restoration of Adhesives, Bonding Agents, Potting Compound When the cell under a category of repair is not shaded, the items listed under that requirement should be reviewed for applicability, based on the repair design, and only the items pertinent to this category of repair should be selected and addressed appropriately. Items not selected need not be addressed. An FAA-approved configuration means a new part (produced under a PC, TSO, or PMA) or a previously approved repaired part. ### Page 17 Appendix 2 17 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 11 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-Mechanical Fatigue b. Oxidation c. Corrosion d. Elevated Temperature- Induced Changes (Creep, Diffusion, Ageing, Temperature Gradients) e. Wear due to: Adhesion, Abrasion, Corrosion, Erosion, Cavitation, Fretting, Oxidation f. High Cycle Fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 18 Appendix 2 18 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 11 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design, and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 19 Appendix 2 19 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 11 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy, as a result of welds or braze, should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size, and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) ### Page 20 Appendix 2 20 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 11 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability, as a result of the coating, should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (Interface Contamination) l. Hydrogen Embrittlement (Plating) m. Compatibility With Base Material/Other Coatings 5. Select surface treatment that applies (without material removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing ### Page 21 Appendix 2 21 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 11 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, re-twisting, reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (chemical, power flash, ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs q. Contamination ### Page 22 Appendix 2 22 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 11 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design, and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s):  Surface finish/texture  Shotpeen Intensity/Coverage  Bearing bore dimensions and location characteristics  Pressure Strength Test  Flow Capacity test  Dimensions, including heat distortion effects 1) Roundness 2) Flatness 3) Parallelism 4) Concentricity 5) True Position Tolerances 6) Edge Distance Requirements 7) Finish Dimensions Requirements 10. Significant Operations Identified for Validation that would include parameter variability limits. ### Page 23 Appendix 2 23 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 11 11. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specs  Quality Requirements  Critical Process Validation needs Applicable 14 CFR Part 33 Requirements Subpart A – General 12. 33.4 Instructions for Continuous Airworthiness (ICA's) 13. 33.5 Instruction manual for installing and operating the engine 14. 33.7 Engine ratings and operating limitations 15. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 16. 33.14 Start-stop cyclic stress (low cycle fatigue) 17. 33.15 Materials 18. 33.17 Fire prevention 19. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) ### Page 24 Appendix 2 24 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 11 20. 33.21 Engine cooling 21. 33.23 Engine mounting attachments and structure 22. 33.25 Accessory attachments 23. 33.27 Turbine, compressor, fan, and turbo-supercharger rotors 24. 33.28 Electrical and electronic control systems 25. 33.29 Instrument connection Repair Process Capability Technical Substantiation Requirements Subpart E – Design and Construction; Turbine Aircraft Engines 26. 33.62 Stress analysis 27. 33.63 Vibration 28. 33.65 Surge and stall characteristics (Note 2) 29. 33.66 Bleed air system 30. 33.67 Fuel system 31. 33.68 Induction system icing (operability aspects) (Note 2) 32. 33.69 Ignitions system 33. 33.71 Lubrication system 34. 33.72 Hydraulic actuating systems 35. 33.73 Power or thrust response 36. 33.74 Continued rotation ### Page 25 Appendix 2 25 CATEGORIES OF REPAIR Req No. Airworthiness Standards to be Substantiated 1 2 3 4 5 6 7 8 9 10 11 Subpart E – Design and Construction; Turbine Aircraft Engines (continued) 37. 33.75 Safety analysis 38. 33.76 Bird ingestion (operability aspects of ingestion) 39. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 40. 33.78 Rain and hail ingestion 41. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 42. 33.83 Vibration test 43. 33.85 Calibration tests 44. 33.87 Endurance test 45. 33.88 Engine overtemperature test 46. 33.89 Operation test (Note 2) 47. 33.90 Initial maintenance inspection 48. 33.91 Engine component tests (HCF/LCF bench testing) 49. 33.92 Rotor locking tests 50. 33.93 Teardown inspection 51. 33.94 Blade containment and rotor unbalance tests (weight changes) 52. 33.95 Engine-propeller system tests 53. 33.96 Engine tests in auxiliary power unit (APU) mode 54. 33.97 Thrust reversers 55. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 26 Appendix 2 26 Template 2 REPAIR SUBSTANTIATION CHECKLIST – HIGH PRESSURE TURBINE (HPT) **BLADE PART FAMILY** Categories of HPT Blade Part Family Repair. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Overcoat Repair (without stripping) 2. Strip and Re-coat Repair  This repair removes and replaces all types of coatings. 3. Weld or Braze Repair (excludes detail parts replacement)  Includes restoration of airfoil tip and chord length 4. Weld or Braze Repair  Includes detail parts replacement 5. Surface Treatment Repair Including shot-peen, glass bead peen, and vibratory tumble (e.g.; restoration of surface finish/texture). 6. Blend Repair 7. Blade Internal Cavity Cleaning Repair 8. Sulfidation or Corrosion Repair 9. Assembly and/or Disassembly. This repair removes and replaces details parts without the use of permanent attachment techniques (i.e., welding or brazing), but assembly is either bolted or riveted. ### Page 27 Appendix 2 27 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design, and assess their impact on the part’s airworthiness: ### Page 28 Appendix 2 28 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 29 Appendix 2 29 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) ### Page 30 Appendix 2 30 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability as a result of the coating should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (Interface Contamination) l. Hydrogen Embrittlement (Plating) m. Compatibility With Base Material/Other Coatings ### Page 31 Appendix 2 31 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 5. Select Surface Treatment that applies (Without Material Removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, re-twisting, reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (Chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs q. Contamination ### Page 32 Appendix 2 32 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design, and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight ### Page 33 Appendix 2 33 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen Intensity/Coverage c. Bearing bore dimensions and location characteristics d. Pressure Strength Test e. Flow Capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True Position Tolerances  Edge Distance  Requirements  Finish Dimensions Requirements g. Airfoil Profile  Leading & Trailing Edge Contour  Concave & convex contours  Thickness  Chord & Airfoil Length  Twist/Lean/Bow h. Tip Length i. Airfoil wall thickness 10. Part Weight: a. Mass b. Moment ### Page 34 Appendix 2 34 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 11. Platform width & (angel wing) Cross Notch/Cross Shroud geometry 12. Cooling (Total flow, flow split, back flow margin, hole exit geometry/angle/location, cross-over hole size, metering plate) Repair Process Capability Technical Substantiation Requirements 13. Verification Plan with Significant Operations Identified for Repair Source Qualification 14. Process Demonstration (including variability requirements) 15. Part Demonstration/Inspection 16. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 17. 33.4 Instructions for Continuous Airworthiness (ICA's) Repair Process Capability Technical Substantiation Requirements 18. 33.5 Instruction manual for installing and operating the engine 19. 33.7 Engine ratings and operating limitations 20. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 21. 33.14 Start-stop cyclic stress (low cycle fatigue) ### Page 35 Appendix 2 35 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 22. 33.15 Materials 23. 33.17 Fire prevention 24. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 25. 33.21 Engine cooling 26. 33.23 Engine mounting attachments and structure 27. 33.25 Accessory attachments 28. 33.27 Turbine, compressor, fan, and turbosupercharger rotors 29. 33.28 Electrical and electronic control systems 30. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 31. 33.62 Stress analysis 32. 33.63 Vibration 33. 33.65 Surge and stall characteristics (Note 2) 34. 33.66 Bleed air system 35. 33.67 Fuel system 36. 33.68 Induction system icing (operability aspects) (Note 2) 37. 33.69 Ignitions system 38. 33.71 Lubrication system 39. 33.72 Hydraulic actuating systems 40. 33.73 Power or thrust response 41. 33.74 Continued rotation 42. 33.75 Safety analysis 43. 33.76 Bird ingestion (operability aspects of ingestion) 44. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 45. 33.78 Rain and hail ingestion 46. 33.79 Fuel burning thrust augmentor ### Page 36 Appendix 2 36 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 Subpart F – Block Tests; Turbine Aircraft Engines 47. 33.83 Vibration test 48. 33.85 Calibration tests 49. 33.87 Endurance test 50. 33.88 Engine overtemperature test 51. 33.89 Operation test (Note 2) 52. 33.90 Initial maintenance inspection 53. 33.91 Engine component tests (HCF/LCF bench testing) 54. 33.92 Rotor locking tests 55. 33.93 Teardown inspection 56. 33.94 Blade containment and rotor unbalance tests (weight changes) 57. 33.95 Engine-propeller system tests 58. 33.96 Engine tests in auxiliary power unit (APU) mode 59. 33.97 Thrust reversers 60. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 37 Appendix 2 37 Template 3 REPAIR SUBSTANTIATION CHECKLIST – LOW PRESSURE COMPRESSOR (LPC) – HIGH PRESSURE COMPRESSOR (HPC) BLADE PART FAMILY Categories of LPC/HPC Blade Part Family Repair. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Strip and Re-coat Repair  This repair removes and replaces any and all types of coatings 2. Weld or Braze Repair (excludes detail parts replacement)  This repair includes restoration of airfoil tip and chord length 3. Weld or Braze Repair  This repair includes detail parts replacement 4. Assembly or Disassembly  This repair removes and replaces detail parts without the use of permanent attachment techniques (i.e., welding or brazing) but assembly is either bolted or riveted. 5. Blend Repair 6. Remove and Restore Anti-gallant Coating 7. Dimensional Restoration by Coating or Plating 8. Straightening, Re-twist or Re-forming Repair  This repair includes dent repair 9. Surface Treatment Repair  This repair includes shot-peen, glass bead peen, vibratory tumble (e.g., restoration of surface finish/texture) ### Page 38 Appendix 2 38 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-Mechanical Fatigue b. Oxidation c. Corrosion d. Elevated Temperature-Induced Changes (Creep, Diffusion, Ageing, Temperature Gradients) e. Wear due to: Adhesion, Abrasion, Corrosion, Erosion, Cavitation, Fretting, Oxidation f. High Cycle Fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 39 Appendix 2 39 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design, and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 40 Appendix 2 40 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) ### Page 41 Appendix 2 41 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability as a result of the coating should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (interface contamination) l. Hydrogen Embrittlement (plating) m. Compatibility with Base Material/Other Coatings 5. Select Surface Treatment that applies (without material removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing ### Page 42 Appendix 2 42 CATEGORIES OF REPAIR Req No. Repair Properties & Requirements to be Identified and Substantiated. 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, re-twisting, reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (Chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs q. Contamination 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. ### Page 43 Appendix 2 43 CATEGORIES OF REPAIR Req No. Repair Properties & Requirements to be Identified and Substantiated. 8. Select all that may be potentially affected by the repair design and evaluate system effect(s): Stress a. Heat Transfer b. Secondary Airflow c. Aerodynamics Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen Intensity/Coverage c. Bearing bore dimensions and location characteristics d. Pressure Strength test e. Flow Capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True Position Tolerances  Edge Distance Requirements  Finish Dimensions Requirements g. Airfoil Profile  Leading & Trailing Edge Contour  Concave & convex contours  Thickness  Chord & Airfoil Length  Twist/Lean/Bow h. Tip Length i. Airfoil wall thickness ### Page 44 Appendix 2 44 CATEGORIES OF REPAIR Req No. Repair Properties & Requirements to be Identified and Substantiated. 9 Critical Measurable Characteristics 10. Dovetail functional fit test 11. Part weight test: a. Mass Weight b. Moment Weight Repair Process Capability Technical Substantiation Requirements 12. Technical Plan with Significant Operations Identified 13. Process Demonstration (including variability requirements) 14. Part Demonstration/Inspection 15. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) 17. 33.5 Instruction manual for installing and operating the engine 18. 33.7 Engine ratings and operating limitations 19. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine cooling 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments ### Page 45 Appendix 2 45 CATEGORIES OF REPAIR Req No. Repair Properties & Requirements to be Identified and Substantiated. 27. 33.27 Turbine, compressor, fan, and turbosupercharger rotors 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 30. 33.62 Stress analysis 31. 33.63 Vibration 32. 33.65 Surge and stall characteristics (Note 2) 33. 33.66 Bleed air system 34. 33.67 Fuel system 35. 33.68 Induction system icing (operability aspects) (Note 2) 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response 40. 33.74 Continued rotation 41. 33.75 Safety analysis 42. 33.76 Bird ingestion (operability aspects of ingestion) 43. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration test 47. 33.85 Calibration tests 48. 33.87 Endurance test 49. 33.88 Engine overtemperature test 50. 33.89 Operation test (Note 2) 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF bench testing) 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection ### Page 46 Appendix 2 46 CATEGORIES OF REPAIR Req No. Repair Properties & Requirements to be Identified and Substantiated. 55. 33.94 Blade containment and rotor unbalance tests (Weight changes) 56. 33.95 Engine-propeller system tests 57. 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 47 Appendix 2 47 Template 4 **REPAIR SUBSTANTIATION CHECKLIST - LOW PRESSURE TURBINE (LPT)** BLADE PART FAMILIES Categories of LPT Blade Part Family Repair. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Strip and Re-coat Repair  This repair removes and replaces any and all types of coatings 2. Overcoat Repair (without stripping) 3. Weld or Braze Repair (excludes detail part replacement)  Includes restoration of airfoil tip and chord length 4. Weld or Braze Repair  Includes detail part replacement 5. Sulfidation or Corrosion Repair 6. Blend Repair 7. Straightening, Re-twist, or Reforming Repair 8. Surface Treatment Repair  This repair includes shot peen, glass bead peen, vibratory tumble (e.g., restoration of surface finish/texture) ### Page 48 Appendix 2 48 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-Mechanical Fatigue b. Oxidation c. Corrosion d. Elevated Temperature-Induced Changes (Creep, Diffusion, Ageing, Temperature Gradients) e. Wear due to: Adhesion, Abrasion, Corrosion, Erosion, Cavitation, Fretting, Oxidation f. High Cycle Fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 49 Appendix 2 49 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design, and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 50 Appendix 2 50 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Coating Material Properties, Characteristics & Processes: a. Deposited Material Composition b. Thickness, Coverage & Uniformity c. Microstructure d. Hardness e. Sintering f. Strip Process g. Residual Stress h. Lubricant Properties i. Spalling Resistance j. Thermal Resistance k. Erosion Resistance l. Bonding (Interface Contamination) m. Environmental Resistance n. Diffusion Zone o. Hydrogen Embrittlement Free p. (Plating) q. Compatibility With Base Material ### Page 51 Appendix 2 51 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 5. Select Surface Treatment that applies (without material removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (Chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs q. Contamination 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. ### Page 52 Appendix 2 52 CATEGORIES OF REPAIR Req No. Repair Properties & Requirements to be Identified and Substantiated. 8. Select all that may be potentially affected by the repair design, and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen Intensity/Coverage c. Bearing bore dimensions and location characteristics d. Pressure Strength test e. Flow Capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True Position Tolerances  Edge Distance Requirements  Finish Dimensions Requirements g. Airfoils Profile  Leading & Trailing Edge Contour  Concave & convex contours  Thickness  Chord & Airfoil Length  Twist/Lean/Bow h. Tip Length i. Airfoil wall thickness j. Throat Area ### Page 53 Appendix 2 53 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Critical Measurable Characteristics 10. Part Weight: a. Moment b. Mass 11. Platform width & (angel wing) Cross Notch/Cross Shroud geometry MPE Repair Process Capability Technical Substantiation Requirements 12. Verification Plan with Significant Operations Identified for Repair Source Qualification 13. Process Demonstration (including variability requirements) 14. Part Demonstration/Inspection 15. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) 17. 33.5 Instruction manual for installing and operating the engine ### Page 54 Appendix 2 54 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Subpart A – General 18. 33.7 Engine ratings and operating limitations 19. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine cooling 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments 27. 33.27 Turbine, compressor, fan, and turbosupercharger rotors 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 30. 33.62 Stress analysis 31. 33.63 Vibration 32. 33.65 Surge and stall characteristics (Note 2) 33. 33.66 Bleed air system 34. 33.67 Fuel system 35. 33.68 Induction system icing (operability aspects) (Note 2) 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response ### Page 55 Appendix 2 55 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Subpart E – Design and Construction; Turbine Aircraft Engines (continued) 40. 33.74 Continued rotation 41. 33.75 Safety analysis 42. 33.76 Bird ingestion (operability aspects of ingestion) 43. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration test 47 33.85 Calibration tests 48. 33.87 Endurance test 49. 33.88 Engine overtemperature test 50. 33.89 Operation test (Note 2) 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF bench testing) 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection 55. 33.94 Blade containment and rotor unbalance tests (weight changes) 56. 33.95 Engine-propeller system tests 57. 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 56 Appendix 2 56 Template 5 **REPAIR SUBSTANTIATION CHECKLIST - COMBUSTOR PART FAMILY** Categories of Combustor Part Family Repairs. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Strip & Recoat Repair  This repair removes and replaces any and all types of coatings. 2. Blend Repair 3. Straightening, Re-twist, or Reforming Repair  This repair includes straightening of bent flanges 4. Weld/Braze Repair  Excludes Detail Part Replacement 5. Weld/Braze Repair  Includes Detail Part Replacement 6. Assembly and/or Disassembly  This repair removes and replaces detail parts without use of permanent attachment technique, (i.e. weld or braze); assembly is either bolted or riveted. 7. Bushing/Helicoil Repair 8. Dimensional Restoration by Coating or Plating. ### Page 57 Appendix 2 57 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-Mechanical Fatigue b. Oxidation c. Corrosion d. Elevated Temperature- Induced Changes (Creep, Diffusion, Ageing, Temperature Gradients) e. Wear due to: Adhesion, Abrasion, Corrosion, Erosion, Cavitation, Fretting, Oxidation f. High Cycle Fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 58 Appendix 2 58 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 59 Appendix 2 59 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) Material Properties/Degradation Modes/Product Qualities/etc. Technical Substantiation Requirements 4. Coating & Plating Material Properties Characteristics & Processes: a. Deposit material composition b. Thickness, Coverage, and Uniformity c. Microstructure d. Hardness e. Sintering f. Strip process g. Residual stress h. Lubricant properties i. Spalling Resistance j. Thermal Resistance k. Erosion Resistance l. Bonding (Interface m. Contamination) n. Environmental Resistance o. Diffusion Zone p. Hydrogen Embrittlement Free Plating q. Compatibility with base material ### Page 60 Appendix 2 60 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 5. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and location characteristics d. Pressure strength test e. Flow capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True position tolerances  Edge distance requirements  Finish dimensions requirements ### Page 61 Appendix 2 61 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Retwisting, Re-forming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (Chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs q. Contamination 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. ### Page 62 Appendix 2 62 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8. Select all that may be potentially affected by the repair design, and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen Intensity/Coverage c. Bearing bore dimensions and location characteristics d. Pressure Strength test e. Flow Capacity test f. Dimensions, including heat distortion effects g. Roundness h. Flatness i. Parallelism j. Concentricity k. True Position Tolerances l. Edge Distance Requirements m. Finish Dimensions Requirements n. Diameter/Locating o. Air Swirler Features p. Mixing Air (dilution) Features q. Datum Location Features r. Air Cooling Hole Diameter s. Flowpath Exit Features t. Sealing Features u. Aft Seal v. Fuel Nozzles w. Igniter interfaces x. Flanges ### Page 63 Appendix 2 63 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 10. Cooling Feature Characteristics: a. Airflow b. Hole Diameter c. Blocked Hole Quantity/Location d. Cooling Slot Height/Length/Location e. Quantity of Holes/Slots 11. Thermal Barrier Coating: a. Thickness b. Coverage c. Type Repair Process Capability Technical Substantiation Requirements 12. Verification Plan with Significant Operations Identified for Repair Source Qualification ### Page 64 Appendix 2 64 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Repair Process Capability Technical Substantiation Requirements 13. Process Demonstration Including: a. Variability Requirements 14. Part Demonstration/Inspection 15. Manufacturing Requirements for fabrication of repair details or replacement sections to accomplish repair: a. Drawings/Specifications b. Quality Requirements c. Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) 17. 33.5 Instruction Manual for Installing and Operating the Engine 18. 33.7 Engine Ratings and Operating Limitations 19. 33.8 Selection of Engine Power and Thrust Ratings Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments ### Page 65 Appendix 2 65 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 27. 33.27 Turbine, compressor, fan, and turbo supercharger rotors 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 30. 33.62 Stress analysis 31. 33.63 Vibration 32. 33.65 Surge and stall characteristics, (Note 2) 33. 33.66 Bleed air system 34. 33.67 Fuel system 35. 33.68 Induction system icing, (operability aspects) (Note 2) 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response 40. 33.74 Continued rotation 41. 33.75 Safety analysis 42. 33.76 Bird ingestion (operability aspects of ingestion) 43. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration test 47. 33.85 Calibration tests 48. 33.87 Endurance tests 49. 33.88 Engine overtemperature test 50. 33.89 Operation test (Note 2) 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF Bench Testing) 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection ### Page 66 Appendix 2 66 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 55. 33.94 Blade containment and rotor unbalance tests (weight changes) 56. 33.95 Engine-propeller system tests 57. 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33-Appendix A – Instructions for Continued Airworthiness Part 33-Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 67 Appendix 2 67 Template 6 REPAIR SUBSTANTIATION CHECKLIST - EXTERNALS PART FAMILY (Tubes, Manifolds, Ducts, Brackets) Categories of Externals (Tubes, Manifolds, Ducts, Brackets) Part Family. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Assembly and/or Disassembly  This repair assembles, disassembles, removes and replaces detail parts, or subassemblies without use of permanent attachment techniques (i.e.; welding or brazing). Assembly is either bolted or riveted. 2. Weld or Braze Repair  This repair excludes detail part replacement 3. Weld or Braze Repair  Includes detail part replacement 4. Blend Repair 5. Sulfidation or Corrosion Repair 6. Dimensional Restoration by Coating or Plating 7. Bushing/Helicoil Repair 8. Straightening, Re-twist or Reforming Repair  This repair includes dent repair 9. Repairs to Restore Adhesives, Bonding Agents, Potting Compounds. 10. Machining Repair  This repair includes lapping, skim cut, non-conventional machining ### Page 68 Appendix 2 68 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 69 Appendix 2 69 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 70 Appendix 2 70 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Coating & Plating Material Properties Characteristics & Processes: a. Deposited Material Composition b. Thickness, Coverage & Uniformity c. Microstructure d. Hardness e. Sintering f. Strip Process g. Residual Stress h. Lubricant Properties i. Spalling Resistance j. Thermal Resistance k. Erosion Resistance l. Bonding (Interface Contamination) m. Environmental Resistance n. Diffusion Zone o. Hydrogen Embrittlement Free (Plating) p. Compatibility With Base Material q. 5. Select Surface Treatment that applies (without material removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing ### Page 71 Appendix 2 71 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, re-twisting, reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (Chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs q. Contamination ### Page 72 Appendix 2 72 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and location characteristics d. Pressure strength test e. Flow capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True position tolerances  Edge distance requirements  Finish dimensions requirements 10. Coating Coverage Definition 11. Blend Area Proximity Limits Defined ### Page 73 Appendix 2 73 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 10 Repair Process Capability Technical Substantiation Requirements 12. Verification Plan with Significant Operations Identified for Repair Source Qualification 13. Process Demonstration (including variability requirements) 14. Part Demonstration/Inspection 15. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) 17. 33.5 Instruction manual for installing and operating the engine 18. 33.7 Engine ratings and operating limitations 19. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine cooling 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments 27. 33.27 Turbine, compressor, fan, and turbosupercharger rotors ### Page 74 Appendix 2 74 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 10 Subpart B – Design and Construction; General 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 30. 33.62 Stress analysis 31. 33.63 Vibration 32. 33.65 Surge and stall characteristics 33. 33.66 Bleed air system 34. 33.67 Fuel system 35. 33.68 Induction system icing (operability aspects) (Note 2) 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response 40. 33.74 Continued rotation 41. 33.75 Safety analysis 42. 33.76 Bird ingestion (operability aspects of ingestion) 43. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration test 47. 33.85 Calibration tests 48. 33.87 Endurance test 49. 33.88 Engine overtemperature test ### Page 75 Appendix 2 75 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 10 Subpart F – Block Tests; Turbine Aircraft Engines 50. 33.89 Operation test 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF bench testing) 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection 55. 33.94 Blade containment and rotor unbalance tests (weight changes) 56. 33.95 Engine-propeller system tests 57. 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 76 Appendix 2 76 Template 7 **REPAIR SUBSTANTIATION CHECKLIST - FUEL NOZZLE PART FAMILY** Categories of Fuel Nozzle Part Family Repair. Determine which repair description best fits the repair proposal based. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Blend Repair 2. Thread Restoration and Functional Testing. 3. Assembly and/or Disassembly  Repair removes and replaces detail parts without use of permanent attachment techniques, (i.e. welding or brazing) but assembly is either bolted or riveted. 4. Machining Repair  Includes lapping, skim cut, non-conventional machining. 5. Weld or Braze Repair  Excludes Detail Part Replacement 6. Weld or Braze Repair  Includes Detail Part Replacement 7. Dimensional Restoration By Coating or Plating ### Page 77 Appendix 2 77 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 78 Appendix 2 78 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, dwell time) d. Creep e. Tensile Properties (yield, strength, elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 79 Appendix 2 79 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability as a result of the coating should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (Interface Contamination) l. Hydrogen Embrittlement (plating) m. Compatibility With Base Material/Other Coatings ### Page 80 Appendix 2 80 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 5. Select Surface Treatment that applies (without material removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs q. Contamination 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. ### Page 81 Appendix 2 81 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 8. Select all that may be potentially affected by the repair design and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and location characteristics d. Pressure strength test e. Flow capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True position tolerances  Edge distance requirements  Finish dimensions requirements g. Diameter/locating h. Air swirler features i. Mixing air (dilution) features j. Datum location features k. Air cooling hole diameter l. Flowpath exit features m. Aft seal n. Flanges o. Igniter interfaces ### Page 82 Appendix 2 82 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated, Cont’d. 7 Critical Measurable Characteristics 10. Material Debit Due To: a. Heat Treat b. Weld, Braze, Coat or Plate Processes c. Machine Process d. Blend e. Hone f. Lap g. Grit Blast h. Strip 11. Flow Volume 12. Flow Pattern 13. Pressure/Leak Test Repair Process Capability Technical Substantiation Requirements 14. Verification Plan with Significant Operations Identified for Repair Source Qualification 15. Process Demonstration (including variability requirements) 16. Part Demonstration/Inspection 17. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 18. 33.4 Instructions for Continuous Airworthiness (ICA's) 19. 33.5 Instruction manual for installing and operating the engine 20. 33.7 Engine ratings and operating limitations 21. 33.8 Selection of engine power and thrust ratings ### Page 83 Appendix 2 83 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 7 Subpart B – Design and Construction; General 22. 33.14 Start-stop cyclic stress (Low cycle fatigue) 23. 33.15 Materials 24. 33.17 Fire prevention 25. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 26. 33.21 Engine cooling 27. 33.23 Engine mounting attachments and structure 28. 33.25 Accessory attachments 29. 33.27 Turbine, compressor, fan, and turbo supercharger rotors 30. 33.28 Electrical and electronic control systems 31. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 32. 33.62 Stress analysis 33. 33.63 Vibration 34. 33.65 Surge and stall characteristics (Note 2) 35. 33.66 Bleed air system 36. 33.67 Fuel system 37. 33.68 Induction system icing (operability aspects) (Note 2) 38. 33.69 Ignitions system 39. 33.71 Lubrication system 40. 33.72 Hydraulic actuating systems 41. 33.73 Power or thrust response 42. 33.74 Continued rotation 43. 33.75 Safety analysis 44. 33.76 Bird ingestion (operability aspects of ingestion) 45. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 46. 33.78 Rain and hail ingestion 47. 33.79 Fuel burning thrust augmentor ### Page 84 Appendix 2 84 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 7 Material Properties/Degradation Modes/Product Qualities/etc. Technical Substantiation Requirements Subpart F – Block Tests; Turbine Aircraft Engines 48. 33.83 Vibration test 49. 33.85 Calibration tests 50. 33.87 Endurance test 51. 33.88 Engine overtemperature test 52. 33.89 Operation test (Note 2) 53. 33.90 Initial maintenance inspection 54. 33.91 Engine component tests (HCF/LCF bench testing) 55. 33.92 Rotor locking tests 56. 33.93 Teardown inspection 57. 33.94 Blade containment and rotor unbalance tests (weight changes) 58. 33.95 Engine-propeller system tests 59. 33.96 Engine tests in auxiliary power unit (APU) mode 60. 33.97 Thrust reversers 61. 33.99 General conduct of block tests Part 33 Appendix A – Instructions for Continued Airworthiness Part 33 Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 85 Appendix 2 85 Template 8 **REPAIR SUBSTANTIATION CHECKLIST - GEARBOX HOUSING ASSEMBLY** **PART FAMILY (SHAFTS, GEARS, HOUSINGS)** Categories of Gearbox Housing Assembly Part Family (shafts, gears, housings). Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Restoration of Protective Coating  Includes Touch Up Coating 2. Weld or Braze Repair  This repair excludes detail part replacement 3. Weld or Braze Repair  Includes detail part replacement 4. Assembly and/or Disassembly  This repair assembles, disassembles, removes and replaces detail parts, or subassemblies without use of permanent attachment techniques (i.e.; welding or brazing). Assembly is either bolted or riveted. 5. Sulfidation or Corrosion Repair 6. Blend Repair 7. Dimensional Restoration by Coating or Plating 8. Bushing/Helicoil Repair 9. Straightening, Re-twist, or Reforming Repair  This repair includes straightening of bent knife edges 10. Surface Treatment Repair  This repair includes peening, vibratory tumble (e.g.; restoration of surface finish/texture) 11. Machining Repair  This repair includes lapping, skim cut, non-conventional machining 12. Restoration of Adhesives, Bonding Agents, Potting Compounds. ### Page 86 Appendix 2 86 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 87 Appendix 2 87 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 88 Appendix 2 88 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Coating & Plating Material Properties Characteristics & Processes: a. Deposited Material Composition b. Thickness, Coverage & Uniformity c. Microstructure d. Hardness e. Sintering f. Strip Process g. Residual Stress h. Lubricant Properties i. Spalling Resistance j. Thermal Resistance k. Erosion Resistance l. Bonding (Interface Contamination) m. Environmental Resistance n. Diffusion Zone o. Hydrogen Embrittlement Free (Plating) p. Compatibility With Base Material ### Page 89 Appendix 2 89 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 5. Select Surface Treatment that applies (without material removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (Chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs q. Contamination ### Page 90 Appendix 2 90 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight ### Page 91 Appendix 2 91 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. 12 Critical Measurable Characteristics 9. Bearing Bore: a. Dimension b. Location 10. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and location characteristics d. Pressure strength test e. Flow capacity test f. Dimensions, including heat g. distortion effects  Roundness  Flatness  Parallelism  Concentricity  True position tolerances  Edge distance requirements  Finish dimensions requirements ### Page 92 Appendix 2 92 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 12 Critical Measurable Characteristics continued 11 Oil Nozzle Flow Test Repair Process Capability Technical Substantiation Requirements 12. Verification Plan with Significant Operations Identified for Repair Source Qualification 13. Process Demonstration (including variability requirements) 14. Part Demonstration/Inspection 15. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) 17. 33.5 Instruction manual for installing and operating the engine 18. 33.7 Engine ratings and operating limitations 19. 33.8 Selection of engine power and thrust ratings ### Page 93 Appendix 2 93 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 12 Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine cooling 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments 27. 33.27 Turbine, compressor, fan, and turbo supercharger rotors 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 30. 33.62 Stress analysis 31. 33.63 Vibration 32. 33.65 Surge and stall characteristics (Note 2) 33. 33.66 Bleed air system 34. 33.67 Fuel system 35. 33.68 Induction system icing (operability aspects) (Note 2) 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response 40. 33.74 Continued rotation 41. 33.75 Safety analysis 42. 33.76 Bird ingestion (operability aspects of ingestion) ### Page 94 Appendix 2 94 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 12 Subpart E – Design and Construction; Turbine Aircraft Engines 43. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration test 47. 33.85 Calibration tests 48. 33.87 Endurance test 49. 33.88 Engine overtemperature test 50. 33.89 Operation test (Note 2) 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF bench testing) Subpart F – Block Tests; Turbine Aircraft Engines 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection 55. 33.94 Blade containment and rotor unbalance tests (weight changes) 56. 33.95 Engine-propeller system tests 57. 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 95 Appendix 2 95 Template 9 REPAIR SUBSTANTIATION CHECKLIST – LOW PRESSURE COMPRESSOR (LPC) – HIGH PRESSURE COMPRESSOR (HPC) STATOR PART FAMILY – VANE **SECTOR (AND FULL RING) TYPE STATORS** Categories of LPC-HPC Stator Repair. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Restoration of Protective Coating (Paint, Aluminizing, Oil, etc.)  This repair includes touch-up coating 2. Weld or Braze Repair  This repair excludes detail part replacement 3. Weld or Braze Repair  This repair includes detail part replacement 4. Assembly and/or Disassembly  This repair assembles, disassembles, removes and replaces detail parts, or sub - assemblies without use of permanent attachment techniques (i.e.; welding or brazing). Assembly is either bolted or riveted 5. Blend Repair 6. Dimensional Restoration by Coating or Plating 7. Surface Treatment Repair  This repair includes peening, vibratory tumble (e.g.; restoration of surface finish/texture) 8. Straightening, Re-twist, or Reforming Repair  This repair includes straightening of bent flanges 9. Restoration of Adhesives, Bonding Agents & Potting Compounds ### Page 96 Appendix 2 96 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 97 Appendix 2 97 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, dwell time) d. Creep e. Tensile Properties (yield, strength, elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 98 Appendix 2 98 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Coating & Plating Material Properties Characteristics & Processes: a. Deposited Material Composition b. Thickness, Coverage & Uniformity c. Microstructure d. Hardness e. Sintering f. Strip Process g. Residual Stress h. Lubricant Properties i. Spalling Resistance j. Thermal Resistance k. Erosion Resistance l. Bonding (Interface Contamination) m. Environmental Resistance n. Diffusion Zone o. Hydrogen Embrittlement Free (Plating) p. Compatibility With Base Material ### Page 99 Appendix 2 99 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 5. Select Surface Treatment that applies (without material removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (Chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs q. Contamination 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. ### Page 100 Appendix 2 100 CATEGORIES OF REPAIR Req. No. Repair Design Requirements to be Identified and Substantiated, Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 Critical Measurable Characteristics 8. Select all that may be potentially affected by the repair design and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen Intensity/Coverage c. Bearing bore dimensions and location characteristics d. Pressure Strength Test e. Flow Capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True Position Tolerances  Edge Distance  Requirements  Finish Dimensions Requirements g. Airfoil Profile h. Leading & Trailing Edge Contours i. Concave & Convex Contours j. Thickness k. Chord & Tip Length l. Twist/Lean/Bow Critical Measurable Characteristics 10. Outer Band Rail Functional Fit 11. Inner Band Arc Length 12. Outer Band to Inner Band Dim Relationship 13. Assembled Honeycomb Inner Radius ### Page 101 Appendix 2 101 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 9 Repair Process Capability Technical Substantiation Requirements 14. Verification Plan with Significant Operations Identified for Repair Source Qualification 15. Process Demonstration (including variability requirements) 16. Part Demonstration/Inspection 17. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 18. 33.4 Instructions for Continuous Airworthiness (ICA's) 19. 33.5 Instruction manual for installing and operating the engine 20. 33.7 Engine ratings and operating limitations 21. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 22. 33.14 Start-stop cyclic stress (low cycle fatigue) 23. 33.15 Materials 24. 33.17 Fire prevention 25. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 26. 33.21 Engine cooling 27. 33.23 Engine mounting attachments and structure 28. 33.25 Accessory attachments ### Page 102 Appendix 2 102 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 9 Repair Process Capability Technical Substantiation Requirements Subpart B – Design and Construction; General 29. 33.27 Turbine, compressor, fan, and turbosupercharger 30. 33.28 Electrical and electronic control systems 31. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 32. 33.62 Stress analysis 33. 33.63 Vibration 34. 33.65 Surge and stall characteristics (Note 2) 35. 33.66 Bleed air system 36. 33.67 Fuel system 37. 33.68 Induction system icing (operability aspects) (Note 2) 38. 33.69 Ignitions system 39. 33.71 Lubrication system 40. 33.72 Hydraulic actuating systems 41. 33.73 Power or thrust response 42. 33.74 Continued rotation 43. 33.75 Safety analysis 44. 33.76 Bird ingestion (operability aspects of ingestion) 45. 33.77 Foreign object ingestion (operability aspects of ingestion) 46. 33.78 Rain and hail ingestion 47. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 48. 33.83 Vibration test 55. 33.85 Calibration tests 49. 33.87 Endurance test 50. 33.88 Engine overtemperature test 51. 33.89 Operation test (Note 2) ### Page 103 Appendix 2 103 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 52. 33.90 Initial maintenance inspection 53. 33.91 Engine component tests (HCF/LCF bench testing) 54. 33.92 Rotor locking tests 55. 33.93 Teardown inspection 56. 33.94 Blade containment and rotor unbalance tests (weight changes) 57. 33.95 Engine-propeller system tests 58. 33.96 Engine tests in auxiliary power unit (APU) mode 59. 33.97 Thrust reversers 60. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 104 Appendix 2 104 Template 10 REPAIR SUBSTANTIATION CHECKLIST –LOW PRESSURE COMPRESSOR (LPC) – HIGH PRESSER COMPRESSOR (HPC) STATOR PART FAMILY – FIXED VANE TYPE STATORS (CANTILEVERED AT O.D.) Categories of LPC-HPC Stator Repair. Determine which repair description best fits the repair proposal based. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Dimensional Restoration by Coating or Plating 2. Weld or Braze Repair  This repair excludes detail part replacement 3. Blend Repair 4. Surface Treatment Repair  This repair includes peening, vibratory tumble (e.g.; restoration of surface finish/texture) ### Page 105 Appendix 2 105 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 106 Appendix 2 106 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 107 Appendix 2 107 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability as a result of the coating should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (interface contamination) l. Hydrogen Embrittlement (plating) m. Compatibility with Base Material/Other Coatings ### Page 108 Appendix 2 108 CATEGORIES OF REPAIR Req No. Repair Properties & Requirement to be Identified and Substantiated. 5. Select Surface Treatment that applies (without material removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (Chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs Contamination ### Page 109 Appendix 2 109 CATEGORIES OF REPAIR Req No. Repair Properties & Requirement to be Identified and Substantiated. 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and d. location characteristics e. Pressure strength test f. Flow capacity test g. Dimensions, including heat distortion effects:  Roundness  Flatness  Parallelism  Concentricity  True position tolerances  Edge distance requirements  Finish dimensions requirements Airfoil Profile  Leading & Trailing Edge Contours  Concave & Convex Contours  Thickness  Chord & Tip Length Twist/Lean/Bow ### Page 110 Appendix 2 110 CATEGORIES OF REPAIR Repair Properties & Requirement to be Identified and Substantiated. 1 2 3 4 Critical Measurable Characteristics 10. Outer Band Rail Functional Fit 11. Inner Band Arc Length 12. Outer Band to Inner Band Dim Relationship 13. Assembled Honeycomb Inner Radius Repair Process Capability Technical Substantiation Requirements 14. Technical Plan with Significant Operations Identified 15. Process Demonstration (including variability requirements) 16. Part Demonstration/Inspection 17. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements ### Page 111 Appendix 2 111 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 4 Applicable 14 CFR Part 33 Requirements Subpart A – General 18. 33.4 Instructions for Continuous Airworthiness (ICA's) 19. 33.5 Instruction manual for installing and operating the engine 20. 33.7 Engine ratings and operating limitations 21. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 22. 33.14 Start-stop cyclic stress (low cycle fatigue) 23. 33.15 Materials 24. 33.17 Fire prevention 25. 33.19 Durability(Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 26. 33.21 Engine cooling 27. 33.23 Engine mounting attachments and structure 28 33.25 Accessory attachments 29. 33.27 Turbine, compressor, fan, and turbosupercharger rotors 30. 33.28 Electrical and electronic control systems 31. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 32. 33.62 Stress analysis 33. 33.63 Vibration 34. 33.65 Surge and stall characteristics (Note 2) 35. 33.66 Bleed air system 36. 33.67 Fuel system 37. 33.68 Induction system icing (operability aspects) (Note 2) 38. 33.69 Ignitions system 39. 33.71 Lubrication system 40. 33.72 Hydraulic actuating systems 41. 33.73 Power or thrust response ### Page 112 Appendix 2 112 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 4 Subpart E – Design and Construction; Turbine Aircraft Engines (continued) 42. 33.74 Continued rotation 43. 33.75 Safety analysis 44. 33.76 Bird ingestion (operability aspects of ingestion) 45. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 46. 33.78 Rain and hail ingestion 47. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 48. 33.83 Vibration tests 49. 33.85 Calibration tests 50. 33.87 Endurance tests 51. 33.88 Engine overtemperature test 52. 33.89 Operation test (Note 2) 53. 33.90 Initial maintenance inspection 54. 33.91 Engine component tests (HCF/LCF bench testing) 55. 33.92 Rotor locking tests 56. 33.93 Teardown inspection 57. 33.94 Blade containment and rotor unbalance tests (Weight changes) 58. 33.95 Engine-propeller system tests 59. 33.96 Engine tests in auxiliary power unit (APU) mode 60. 33.97 Thrust reversers 61. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 113 Appendix 2 113 Template 11 **REPAIR SUBSTANTIATION CHECKLIST -- MAJOR ENGINE CASES** Categories of Major Cases Part Family. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Weld or Braze Repair  This repair includes detail part replacement 2. Weld or Braze Repair  This repair excludes detail part replacement 3. Straightening, Re-twist or Reforming Repair  This repair includes dent repair 4. Dimensional Restoration by Coating or Plating 5. Restoration of Adhesives, Bonding Agents, Potting Compound. 6. Bushing or Helicoil Repair 7. Restoration of Protective Coating  Includes touch-up coating 8. Assembly and/or Disassembly  This repair assembles, disassembles, removes and replaces detail parts, or sub -assemblies without the use of permanent attachment techniques (i.e.; welding or brazing). Assembly is either bolted or riveted. 9. Remove and Restore Anti-gallant 10. Blend Repair ### Page 114 Appendix 2 114 CATEGORIES OF REPAIRS Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 115 Appendix 2 115 CATEGORIES OF REPAIR Req. No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated 1 2 3 4 5 6 7 8 9 10 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 116 Appendix 2 116 CATEGORIES OF REPAIRS Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. 4 Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability as a result of the coating should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (Interface Contamination) l. Hydrogen Embrittlement (plating) m. Compatibility With Base Material/Other Coatings 5. Select Surface Treatment that applies (Without Material Removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing ### Page 117 Appendix 2 117 CATEGORIES OF REPAIRS Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (chemical, power flash, ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs Contamination ### Page 118 Appendix 2 118 CATEGORIES OF REPAIRS Req No. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design, and evaluate system effect(s): Critical Measurable Characteristics 9. Hole dimensions and location characteristics 10. Flange & Case Wall thickness & configuration 11. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and location characteristics d. Pressure strength test e. Flow capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True position tolerances  Edge distance requirements  Finish dimensions requirements Repair Process Capability Technical Substantiation Requirements 12. Verification Plan with Significant Operations Identified for Repair Source Qualification 13. Process Demonstration (including variability requirements) ### Page 119 Appendix 2 119 CATEGORIES OF REPAIRS Req No. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 14. Part Demonstration/Inspection 15. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) ### Page 120 Appendix 2 120 CATEGORIES OF REPAIRS Req No. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 17. 33.5 Instruction manual for installing and operating the engine 18. 33.7 Engine ratings and operating limitations 19. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine cooling 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments 27. 33.27 Turbine, compressor, fan, and turbosupercharger rotors 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 30. 33.62 Stress analysis 31. 33.63 Vibration 32. 33.65 Surge and stall characteristics (Note 2) 33. 33.66 Bleed air system 34. 33.67 Fuel system 35. 33.68 Induction system icing (operability aspects) (Note 2) 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response 40. 33.74 Continued rotation ### Page 121 Appendix 2 121 CATEGORIES OF REPAIRS Req No. Repair Properties and Requirements to be Identified and Substantiated. 1 2 3 4 5 6 7 8 9 10 Subpart F – Block Tests; Turbine Aircraft Engines 41. 33.75 Safety analysis 42. 33.76 Bird ingestion (operability aspects of ingestion) 43. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration test 47. 33.85 Calibration tests 48. 33.87 Endurance test 49. 33.88 Engine overtemperature test 50. 33.89 Operation test (Note 2) 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF bench testing) 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection 55. 33.94 Blade containment and rotor unbalance tests (weight changes) 56. 33.95 Engine-propeller system tests 57. 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 122 Appendix 2 122 Template 12 **REPAIR SUBSTANTIATION CHECKLIST - MAJOR ROTATING (NON-LIFE** **LIMITED) PART FAMILY (EXCLUDING TURBINE SHAFT COUPLING PART** **FAMILY)** Categories of Major Rotating (Non-Life Limited) Part Repairs. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Restoration of Protective Coating (Paint, Aluminizing, Oil, etc.)  Includes touch-up coating 2. Weld or Braze Repair  This repair excludes detail part replacement 3. Assembly and/or Disassembly  This repair assembles, disassembles, removes and replaces detail parts, or sub - assemblies without use of permanent attachment techniques (i.e.; welding or brazing). Assembly is either bolted or riveted 4. Blend Repair 5. Remove and Restore Anti-gallant 6. Dimensional Restoration by Coating or Plating 7. Bushing/Helicoil Repair 8. Honing Repair 9. Machining Repair  This repair includes lapping, skim cut, non-conventional machining ### Page 123 Appendix 2 123 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 124 Appendix 2 124 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, dwell time) d. Creep e. Tensile Properties (yield, strength, elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 125 Appendix 2 125 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Coating & Plating Material Properties Characteristics & Processes: a. Deposited Material Composition b. Thickness, Coverage & Uniformity c. Microstructure d. Hardness e. Sintering f. Strip Process g. Residual Stress h. Lubricant Properties i. Spalling Resistance j. Thermal Resistance k. Erosion Resistance l. Bonding (interface contamination) m. Environmental Resistance n. Diffusion Zone o. Hydrogen Embrittlement Free (plating) p. Compatibility with Base Material ### Page 126 Appendix 2 126 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 5. Select Surface Treatment that applies (Without Material Removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (chemical, power flash, ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs Contamination 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. ### Page 127 Appendix 2 127 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 8. Select all that may be potentially affected by the repair design, and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and location characteristics d. Pressure strength test e. Flow capacity test f. Dimensions, including heat g. Distortion effects  Roundness  Flatness  Parallelism  Concentricity  True Position Tolerances  Edge Distance Requirements  Finish Dimensions Requirements 10. Coating Coverage Definition 11. Blend Area Proximity Limits Defined 12. No Grit Blast/Coating in Fillet Radii ### Page 128 Appendix 2 128 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 9 Repair Process Capability Technical Substantiation Requirements 13. Verification Plan with Significant Operations Identified for Repair Source Qualification 14. Process Demonstration (including variability requirements) 15. Part Demonstration/Inspection 16. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 17. 33.4 Instructions for Continuous Airworthiness (ICA's) 18. 33.5 Instruction manual for installing and operating the engine 19. 33.7 Engine ratings and operating limitations 20. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 21. 33.14 Start-stop cyclic stress (low cycle fatigue) 22. 33.15 Materials 23. 33.17 Fire prevention 24. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 25. 33.21 Engine cooling ### Page 129 Appendix 2 129 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 9 Subpart B – Design and Construction; General 26. 33.23 Engine mounting attachments and structure 27. 33.25 Accessory attachments 28. 33.27 Turbine, compressor, fan, and turbosupercharger 29. 33.28 Electrical and electronic control systems 30. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 31. 33.62 Stress analysis 32. 33.63 Vibration 33. 33.65 Surge and stall characteristics (Note 2) 34. 33.66 Bleed air system 35. 33.67 Fuel system 36. 33.68 Induction system icing (operability aspects) (Note 2) 37. 33.69 Ignitions system 38. 33.71 Lubrication system 39. 33.72 Hydraulic actuating systems 40. 33.73 Power or thrust response 41. 33.74 Continued rotation 42. 33.75 Safety analysis 43. 33.76 Bird ingestion (operability aspects of ingestion) 44. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 45. 33.78 Rain and hail ingestion 46. 33.79 Fuel burning thrust augmentor ### Page 130 Appendix 2 130 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 9 Subpart F – Block Tests; Turbine Aircraft Engines 47. 33.83 Vibration test 48. 33.85 Calibration tests 49. 33.87 Endurance test 50. 33.88 Engine overtemperature test 51. 33.89 Operation test (Note 2) 52. 33.90 Initial maintenance inspection 53. 33.91 Engine component tests (HCF/LCF bench testing) 54. 33.92 Rotor locking tests 55. 33.93 Teardown inspection 56. 33.94 Blade containment and rotor unbalance tests (weight changes) 57. 33.95 Engine-propeller system tests 58. 33.96 Engine tests in auxiliary power unit (APU) mode 59. 33.97 Thrust reversers 60. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B -– Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 131 Appendix 2 131 Template 13 REPAIR SUBSTANTIATION CHECKLIST – HIGH PRESSURE COMPRESSOR (HPC)/HIGH PRESSURE TURBINE (HPT)/LOW PRESSURE TURBINE (LPT) **AIRSEALS (NON-ROTATING) AND SHROUDS (STATIONARY) PART FAMILY** Categories of HPC/HPT/LPT Airseals (non-rotating) and Shrouds (stationary) Part Family Repair. Determine which repair description best fit the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Assembly and/or Disassembly  This repair assembles, disassembles, removes and replaces detail parts, or sub - assemblies without use of permanent attachment techniques (i.e.; welding or brazing). Assembly is either bolted or riveted 2. Blend Repair 3. Strip and Re-coat Repair  This repair removes and replaces any and all types of coatings 4. Dimensional Restoration by Coating or Plating 5. Weld or Braze Repair  This repair excludes detail part replacement) 6. Weld or Braze Repair  This repair includes part detail replacement 7. Straightening, Re-twist or Reforming Repair  This repair includes dent repair 8. Machining Repair  This repair includes lapping, skim cut, non-conventional machining ### Page 132 Appendix 2 132 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 133 Appendix 2 133 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design, and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, dwell time) d. Creep e. Tensile Properties (yield, strength, elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 134 Appendix 2 134 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze, should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability as a result of the coating should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (interface contamination) l. Hydrogen Embrittlement (plating) m. Compatibility with Base Material/Other Coatings ### Page 135 Appendix 2 135 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 5. Select Surface Treatment that applies (Without Material Removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (chemical, power flash, ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs Contamination 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight ### Page 136 Appendix 2 136 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and location characteristics d. Pressure strength test e. Flow capacity test f. Dimensions, including heat distortion effects 1) Roundness 2) Flatness 3) Parallelism 4) Concentricity 5) True Position Tolerances 6) Edge Distance 7) Requirements 8) Finish Dimensions Requirements Critical Measurable Characteristics 10. Coating Coverage Definition: a. No Grit Blast b. No coating in Filet Radii 11. Blend Area Proximity Limits Defined Repair Process Capability Technical Substantiation Requirements 12. Technical Plan with Significant Operations Identified 13. Process Demonstration (including variability requirements) 14. Part Demonstration/Inspection 15. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements ### Page 137 Appendix 2 137 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) 17. 33.5 Instruction manual for installing and operating the engine 18. 33.7 Engine ratings and operating limitations 19. 33.8 Selection of engine power and thrust ratings Applicable 14 CFR Part 33 Requirements Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine cooling 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments 27. 33.27 Turbine, compressor, fan, and turbosupercharger rotors 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 30. 33.62 Stress analysis 31. 33.63 Vibration 32. 33.65 Surge and stall characteristics (Note 2) 33. 33.66 Bleed air system 34. 33.67 Fuel system 35. 33.68 Induction system icing (operability aspects) (Note 2) 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response 40. 33.74 Continued rotation 41. 33.75 Safety analysis ### Page 138 Appendix 2 138 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Subpart E – Design and Construction; Turbine Aircraft Engines 42. 33.76 Bird ingestion (operability aspects of ingestion) 43. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration tests 47. 33.85 Calibration tests 48. 33.87 Endurance tests 49. 33.88 Engine overtemperature test 50. 33.89 Operation test (Note 2) 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF bench testing) 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection 55. 33.94 Blade containment and rotor unbalance tests (Weight changes) 56. 33.95 Engine-propeller system tests 57. 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 139 Appendix 2 139 Template 14 REPAIR SUBSTANTIATION CHECKLIST - STATIC STRUCTURE PART FAMILY (Ducts, Bearing Housings, Etc.) Categories of Static Structure Parts Family Repairs. Determine which repair description best fits the repair proposal based. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES OF** **REPAIRS** **REPAIR DESCRIPTION** 1. Blend Repair 2. Weld/Braze Repairs  Excludes Detail Part Replacement 3. Weld/Braze Repairs  Includes Detail Part Replacement 4. Assembly and/or Disassembly  This repair removes and replaces detail parts without the use of permanent attachment. Techniques, i.e., welded or brazed, assembly is either bolted or riveted. 5. Dimensional Restoration Coating or Plating 6. Straightening, Re-twist or Reforming Repair  This repair includes dent repair. ### Page 140 Appendix 2 140 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperatureinduced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 141 Appendix 2 141 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design, and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (yield, strength, elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 142 Appendix 2 142 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) ### Page 143 Appendix 2 143 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability, as a result of the coating, should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (interface contamination) l. Hydrogen Embrittlement (Plating) m. Compatibility with Base Material/Other Coatings Material Properties/Degradation Modes/Product Qualities/etc. Technical Substantiation Requirements 5. Select Surface Treatment that applies (Without Material Removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing ### Page 144 Appendix 2 144 CATEGORIES OF REPAIR Req No Repair Properties & Requirement to be Identified and Substantiated. 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Re-forming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (Chemical, power flash, Ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs Contamination 7. Cleaning Properties, Characteristics & Material Property Debits: a. Chemical (solutions, etc.) b. Grit Blast (,pressure media etc.) c. Power Flush (pressure, solution time, temp, etc.) d. Ultrasonic (solution frequency, time, etc.) e. Furnace (time, temp, atmosphere, etc.) ### Page 145 Appendix 2 145 CATEGORIES OF REPAIR Req No Repair Properties & Requirement to be Identified and Substantiated. 8. Select all that may be potentially affected by the repair design and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen Intensity/Coverage c. Bearing bore dimensions and location characteristics d. Pressure Strength Test e. Flow Capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True Position Tolerances  Edge Distance  Requirements  Finish Dimensions Requirements 10. Parent material thickness reduction assessment 11. Dimensional & Tolerance Reverse engineered parts Repair Process Capability Technical Substantiation Requirements 12. Verification Plan with Significant Operations Identified for Repair Source Qualification ### Page 146 Appendix 2 146 CATEGORIES OF REPAIR Req No Repair Properties & Requirement to be Identified and Substantiated. 13. Process Demonstration:  Including variability requirements 14. Part Demonstration/Inspection 15. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) 17. 33.5 Instruction manual for installing and operating the engine 18. 33.7 Engine ratings and operating limitations 19. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) (weight and CG location changes effects on disks) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine cooling 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments 27. 33.27 Turbine, compressor, fan, and turbo supercharger rotors ### Page 147 Appendix 2 147 CATEGORIES OF REPAIR Req No Repair Properties & Requirement to be Identified and Substantiated. 6 Subpart B – Design and Construction; General; continued 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument Control Subpart E – Design and Construction; Turbine Aircraft Engines 30. 33.62 Stress analysis 31. 33.63 Vibration 32. 33.65 Surge and stall characteristics (Note 2) 33. 33.66 Bleed air system 34. 33.67 Fuel system ### Page 148 Appendix 2 148 CATEGORIES OF REPAIR Req No Repair Properties and Requirements to be Identified and Substantiated. 6 Subpart E – Design and Construction; Turbine Aircraft Engines 35. 33.68 Induction system icing 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response 40. 33.74 Continued rotation 41. 33.75 Safety analysis 42. 33.76 Bird ingestion (operability aspects of ingestion) 43. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration test 47. 33.85 Calibration tests 48. 33.87 Endurance test(see Note 2) 49. 33.88 Engine overtemperature test 50 33.89 Operation test (operability aspects) 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF bench testing) 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection 55. 33.94 Blade containment and rotor unbalance tests (weight changes) 56. 33.95 Engine-propeller system tests 57. 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33 —Appendix A – Instructions for Continued Airworthiness DER Part 33— Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 149 Appendix 2 149 Template 15 REPAIR SUBSTANTIATION CHECKLIST – LOW PRESSURE COMPRESSOR (LPC) – HIGH PRESSURE COMPRESSOR (HPC) STATOR PART FAMILY – VARIABLE **VANE TYPE STATORS** Categories of LPC-HPC Stator Repair. Determine which repair description best fits the repair proposal based. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Weld or Braze Repair  This repair excludes detail part replacement 2. Blend Repair 3. Dimensional Restoration by Coating or Plating 4. Surface Treatment Repair  This repair includes peening, vibratory tumble (e.g.; restoration of surface finish/texture) ### Page 150 Appendix 2 150 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High-cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 151 Appendix 2 151 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design, and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 152 Appendix 2 152 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability as a result of the coating should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (interface contamination) l. Hydrogen Embrittlement (plating) m. Compatibility with Base Material/Other Coatings 5. Select Surface Treatment that applies (without material removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing ### Page 153 Appendix 2 153 CATEGORIES OF REPAIR Req No. Repair Properties & Requirement to be Identified and Substantiated. 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (chemical, power flash, ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs Contamination ### Page 154 Appendix 2 154 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design, and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight Critical Measurable Characteristics 9. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and location characteristics d. Pressure strength test e. Flow capacity test f. Dimensions, including heat distortion effects  roundness  flatness  parallelism  concentricity  true position tolerances  edge distance  requirements  finish dimensions requirements g. Airfoil profile  leading & trailing edge contours  concave & convex contours  thickness  chord & tip length  twist/lean/bow Critical Measurable Characteristics 10. Spindle (Trunnion) Diameter 11. Outer Spindle (Trunnion) to Lever Seating Flat 12. Outer Spindle (Trunnion) to Inner Spindle (Trunnion) 13. Outer Spindle (Trunnion) to Inner Spindle (Trunnion) Concentricity ### Page 155 Appendix 2 155 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated, Cont’d. 4 Repair Process Capability Technical Substantiation Requirements 14. Technical Plan with Significant Operations Identified 15. Process Demonstration (including variability requirements) 16. Part Demonstration/Inspection 17. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 18. 33.4 Instructions for Continuous Airworthiness (ICA's) 19. 33.5 Instruction manual for installing and operating the engine 20. 33.7 Engine ratings and operating limitations 21. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 22. 33.14 Start-stop cyclic stress (low cycle fatigue) 23. 33.15 Materials 24. 33.17 Fire prevention 25. 33.19 Durability(Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 26. 33.21 Engine cooling 27. 33.23 Engine mounting attachments and structure 28. 33.25 Accessory attachments 29. 33.27 Turbine, compressor, fan, and turbosupercharger rotors 30. 33.28 Electrical and electronic control systems 31. 33.29 Instrument connection Subpart E – Design and Construction; Turbine Aircraft Engines 32. 33.62 Stress Analysis 33. 33.63 Vibration ### Page 156 Appendix 2 156 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 4 Subpart E – Design and Construction; Turbine Aircraft Engines 34. 33.65 Surge and stall characteristics (Note 2) 35. 33.66 Bleed air system 36. 33.67 Fuel system 37. 33.68 Induction system icing (operability aspects) (Note 2) 38. 33.69 Ignitions system 39. 33.71 Lubrication system 40. 33.72 Hydraulic actuating systems 41. 33.73 Power or thrust response 42. 33.74 Continued rotation 43. 33.75 Safety analysis 44. 33.76 Bird ingestion (operability aspects of ingestion) 45. 33.77 Foreign object ingestion (operability aspects of ingestion) 46. 33.78 Rain and hail ingestion 47. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 48. 33.83 Vibration test 49. 33.85 Calibration tests 50. 33.87 Endurance test 51. 33.88 Engine overtemperature test 52. 33.89 Operation test (Note 2) 53. 33.90 Initial maintenance inspection 54. 33.91 Engine component tests (HCF/LCF bench testing) ### Page 157 Appendix 2 157 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 4 Subpart F – Block Tests; Turbine Aircraft Engines 55. 33.92 Rotor locking tests 56. 33.93 Teardown inspection 57. 33.94 Blade containment and rotor unbalance tests (weight changes) 58. 33.95 Engine-propeller system tests 59. 33.96 Engine tests in auxiliary power unit (APU) mode 60. 33.97 Thrust reversers 61. 33.99 General conduct of block tests Part33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 158 Appendix 2 158 Template 16 **REPAIR SUBSTANTIATION CHECKLIST - HPT VANE PART FAMILY** Categories of HPT Vane Repair. Determine which repair description best fits the repair proposal. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Strip and Re-coat Repair  This repair removes and replaces any and all types of coatings. 2. Weld or Braze Repair (excludes detail parts replacement)  Includes restoration of airfoil tip and chord length 3. Weld or Braze Repair  Includes detail parts replacement 4. Assembly and/or disassembly  This repair removes and replaces details parts without the use of permanent attachment techniques (i.e., welding or brazing) but assembly is either bolted or riveted. 5. Blend Repair 6. Dimensional Restoration by Coating or Plating 7. Straightening, Re-twist or Reforming Repair ### Page 159 Appendix 2 159 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 160 Appendix 2 160 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design, and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (Alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (Consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 161 Appendix 2 161 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability, as a result of the coating, should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (interface contamination) l. Hydrogen Embrittlement (plating) m. Compatibility with Base Material/Other Coatings ### Page 162 Appendix 2 162 CATEGORIES OF REPAIR Req No, Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 5. Select Surface Treatment that applies (Without Material Removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing ### Page 163 Appendix 2 163 CATEGORIES OF REPAIR Req No. Repair Properties & Requirement to be Identified and Substantiated. 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (chemical, power flash, ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs Contamination 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design, and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight ### Page 164 Appendix 2 164 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 7 Critical Measurable Characteristics 9. Dimension of sealing features (leakage, secondary circuits) 10. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen intensity/coverage c. Bearing bore dimensions and location characteristics d. Pressure strength test e. Flow capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True position tolerances  Edge distance  Requirements  Finish dimensions  Requirements g. Airfoils Profile  Leading & trailing edge contour  Concave & convex contours  Thickness  Chord & airfoil length  Twist/lean/bow h. Tip length i. Airfoil wall thickness j. Throat area 11. Cooling (Total flow, flow split, back flow margin, hole exit geometry, allowable plugged holes) Repair Process Capability Technical Substantiation Requirements 12. Technical Plan with Significant Operations Identified 13. Process Demonstration (including variability requirements) ### Page 165 Appendix 2 165 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 7 Repair Process Capability Technical Substantiation Requirements 14. Part Demonstration/Inspection 15. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) 17 33.5 Instruction manual for installing and operating the engine 18. 33.7 Engine ratings and operating limitations 19. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine cooling 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments Subpart B – Design and Construction; General 27. 33.27 Turbine, compressor, fan, and turbosupercharger rotors 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument connection Subpart E – Design and construction; Turbine aircraft Engines 30. 33.62 Stress Analysis 31. 33.63 Vibration ### Page 166 Appendix 2 166 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 32. 33.65 Surge and stall characteristics (Note 2) 33. 33.66 Bleed air system 34. 33.67 Fuel system 35. 33.68 Induction system icing (operability aspects) (Note 2) 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response 40. 33.74 Continued rotation 41. 33.75 Safety analysis 42. 33.76 Bird ingestion (operability aspects of ingestion) 43. 33.77 Foreign object ingestion (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45. 33.79 Fuel burning thrust augmentor Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration test 47. 33.85 Calibration tests 48. 33.87 Endurance test 49. 33.88 Engine overtemperature test 50. 33.89 Operation test (Note 2) 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF bench testing) 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection 55. 33.94 Blade containment and rotor unbalance tests (weight changes) 56. 33.95 Engine-propeller system tests 57 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33 -Appendix A – Instructions for Continued Airworthiness Part 33 -Appendix B – Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions ### Page 167 Appendix 2 167 Template 17 **REPAIR SUBSTANTIATION CHECKLIST - LOW PRESSURE TURBINE (LPT) VANE** **PART FAMILY** Categories of LPT Vane Part Family Repair. Determine which repair description best fit the repair proposal based. If no repair description is appropriate, contact the FAA Advisor for guidance. **CATEGORIES** **OF REPAIRS** **REPAIR DESCRIPTION** 1. Strip and Re-coat Repair  This repair removes and replaces any and all types of coatings 2. Overcoat Repair (without stripping) 3. Weld or Braze Repair (excludes detail part replacement)  Includes restoration of airfoil tip and chord length 4. Weld or Braze Repair  Includes detail part replacement 5. Disassembly and/or Assembly  This repair removes and replaces detail parts without the use of permanent attachment (i.e.; welding or brazing) but assembly is either bolted or riveted. 6. Blend Repair 7. Dimensional Restoration Repair (by coating of plating) 8. Straightening, Re-twist, or Reforming Repair ### Page 168 Appendix 2 168 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 1. Applicable Degradation Modes: Select all that apply based on the function of the part and its operating environment in the engine. This section provides the background for establishing the substantiation requirements. a. Thermo-mechanical fatigue b. Oxidation c. Corrosion d. Elevated temperature-induced changes (creep, diffusion, ageing, temperature gradients) e. Wear due to: adhesion, abrasion, corrosion, erosion, cavitation, fretting, oxidation f. High cycle fatigue g. Rubbing, foreign object impact damage, O3 chemical attack, etc. ### Page 169 Appendix 2 169 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 2. Select all mechanical, metallurgical, and physical properties of the part affected by the repair design, and assess their impact on the part’s airworthiness: Mechanical Properties: a. Stress-Strain b. Fracture Toughness c. Fatigue Strength (S-N, Goodman, Dwell Time) d. Creep e. Tensile Properties (Yield, Strength, Elongation) f. Hardness g. Young’s Modulus h. Natural Frequencies Metallurgical Properties: i. Chemical Composition (alloy constituents) j. Microstructure (grain size – shape - boundary precipitates, gamma prime size and volume fraction, etc.) k. Melting Point l. Corrosion Resistance m. Oxidation Resistance n. Wear Resistance (consider wear types in (1)(e)) o. Crack Propagation Rate Physical Properties: p. Density (weight) q. Coefficient of Thermal Expansion r. Refractive Index (X-Rays) s. Center of Gravity t. Polar Moment of Inertia ### Page 170 Appendix 2 170 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 3. Select all Material Properties/Characteristics for weldments or brazed joints that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s metallurgy as a result of welds or braze should be evaluated for airworthiness. a. Microstructure (grain size, grain shape, grain boundary precipitates, gamma prime size and volume fraction, etc.) b. Porosity (weldment) c. Diffusion Zone (brazing) d. Heat Affected Zone (welding) ### Page 171 Appendix 2 171 CATEGORIES OF REPAIR Req No. Repair Design Requirements to be Identified and Substantiated. Repair Properties and Requirements to be Identified and Substantiated. 4. Select all Coating Properties/Characteristics that apply and evaluate them and their interface with the parent metal. The effect of any changes to the part’s physical and operational capability as a result of the coating should be evaluated for airworthiness. a. Coating Material Composition b. Thickness, Coverage & Uniformity c. Coating and Diffusion Zone Microstructure d. Coating Hardness e. Sintering f. Strip Requirements/Process g. Residual Stress h. Resistance to Spalling i. Thermal Resistance (coefficient of thermal expansion for the coating) j. Erosion Resistance k. Bonding (Interface Contamination) l. Hydrogen Embrittlement (plating) m. Compatibility with Base Material/Other Coatings 5. Select Surface Treatment that applies (Without Material Removal) and evaluate effect(s), if any, on airworthiness: a. Burnishing b. Peening c. Butterfly Polish d. Mass Media Finishing ### Page 172 Appendix 2 172 CATEGORIES OF REPAIR Req No. Repair Properties & Requirement to be Identified and Substantiated. 6. Evaluate any degradation in the part’s function or durability due to the following processes, when applicable, and assess its impact, if any, on existing ICAs. a. Machining, Milling, Broaching, or Grinding b. Non-traditional Machining c. Welding, Brazing or Coating d. Straightening, Re-twisting, Reforming e. Blending f. Honing g. Lapping h. Grit Blast i. Stripping j. Cleaning (chemical, power flash, ultrasonic) k. Residual Plating, Stripping, or Cleaning Agents l. Stress Intensity Factor (Kt) m. Heat Treatment (time, temp, atmosphere, etc.) n. Plating o. Dimensional Short-falls p. Repetitive or Conflicting Repairs Contamination 7. Establish the Applicability of the Repair and the Repair Processing Sequence or evaluate any changes to an existing repair sequence for potential impact on the airworthiness of the part. 8. Select all that may be potentially affected by the repair design and evaluate system effect(s): a. Structural Strength, including major load paths b. Heat Transfer c. Secondary Airflow d. Aerodynamics e. Weight f. Center of Gravity g. Moment of Weight ### Page 173 Appendix 2 173 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Critical Measurable Characteristics 9. Cooling (Total flow, flow split, back flow margin, hole exit geometry/angle/location, cross over hole size, metering plate) 10. Dimension of sealing features (leakage, secondary circuits) 11. Establish Measurable Characteristics and the allowable tolerances for the repaired part features and for any replacement detail(s) and give due consideration to mating part(s): a. Surface finish/texture b. Shotpeen Intensity/Coverage c. Bearing bore dimensions and location characteristics d. Pressure Strength Test e. Flow Capacity test f. Dimensions, including heat distortion effects  Roundness  Flatness  Parallelism  Concentricity  True Position  Tolerances  Edge Distance  Requirements  Finish Dimensions  Requirements g. Airfoils Profile  Leading and Trailing Edge Contour  Concave and convex contours  Thickness  Chord and Airfoil Length  Twist/Lean/Bow h. Tip Length i. Airfoil wall thickness j. Throat Area Repair Process Capability Technical Substantiation Requirements 12. Verification Plan with Significant Operations Identified for Repair Source Qualification 13. Process Demonstration (including variability requirements) 14. Part Demonstration/Inspection ### Page 174 Appendix 2 174 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Repair Process Capability Technical Substantiation Requirements 15. Manufacturing requirements for fabrication of repair details or replacement sections used to accomplish repair:  Drawings/Specifications  Quality Requirements  Source Substantiation Requirements Applicable 14 CFR Part 33 Requirements Subpart A – General 16. 33.4 Instructions for Continuous Airworthiness (ICA's) 17. 33.5 Instruction manual for installing and operating the engine 18. 33.7 Engine ratings and operating limitations 19. 33.8 Selection of engine power and thrust ratings Subpart B – Design and Construction; General 20. 33.14 Start-stop cyclic stress (low cycle fatigue) 21. 33.15 Materials 22. 33.17 Fire prevention 23. 33.19 Durability (Note that 33.19 is associated with 33.27; 33.63; 33.83; 33.87; 33.88; and 33.90) 24. 33.21 Engine cooling 25. 33.23 Engine mounting attachments and structure 26. 33.25 Accessory attachments ### Page 175 Appendix 2 175 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Subpart B – Design and Construction; General 27. 33.27 Turbine, compressor, fan, and turbosupercharger rotors 28. 33.28 Electrical and electronic control systems 29. 33.29 Instrument connection Subpart E – Design and construction; Turbine Aircraft Engines 30. 33.62 Stress analysis 31. 33.63 Vibration 32. 33.65 Surge and stall characteristics (Note 2) 33. 33.66 Bleed air systems 34. 33.67 Fuel system 35. 33.68 Induction system icing (operability aspects) (Note 2) 36. 33.69 Ignitions system 37. 33.71 Lubrication system 38. 33.72 Hydraulic actuating systems 39. 33.73 Power or thrust response 40. 33.74 Continued rotation 41. 33.75 Safety analysis 42. 33.76 Bird ingestion (operability aspects of ingestion) 43. 33.77 Foreign object ingestion—ice (operability aspects of ingestion) 44. 33.78 Rain and hail ingestion 45. 33.79 Fuel burning thrust augmentor ### Page 176 Appendix 2 176 CATEGORIES OF REPAIR Req No. Repair Properties and Requirements to be Identified and Substantiated. 8 Subpart F – Block Tests; Turbine Aircraft Engines 46. 33.83 Vibration test 47. 33.85 Calibration tests 48. 33.87 Endurance test 49. 33.88 Engine overtemperature test 50. 33.89 Operation test (Note 2) 51. 33.90 Initial maintenance inspection 52. 33.91 Engine component tests (HCF/LCF bench testing) 53. 33.92 Rotor locking tests 54. 33.93 Teardown inspection 55. 33.94 Blade containment and rotor unbalance tests (weight changes) 56. 33.95 Engine-propeller system tests 57. 33.96 Engine tests in auxiliary power unit (APU) mode 58. 33.97 Thrust reversers 59. 33.99 General conduct of block tests Part 33 - Appendix A – Instructions for Continued Airworthiness Part 33 - Appendix B- Certification Standard Atmospheric Concentrations of Rain and Hail Part 34 – Exhaust Emissions --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.