AC 33-2A 5 June 1972 NOTE 3. Accessory drive or mounting provisions:
Maximum Rotation Speed Maximum Torque Overhang Accessory Engine Models Facing Ratio (in. -1b.) Moment Drive RJ123 RJC123 Drive Pad to Engine Cont. Static (in.-lb.)
Starter CC : 1 Starter * CC : 1 Generator * C : 1 etc. etc. etc. etc.
Alternator Vacuum pump Fuel pump Fuel pump (plunger) Tachometer Propeller Governor Standard - * Optional - *x "C' Clockwise, "CC' Counter Clockwise "-" does not apply NOTE 4. Engine rating basis: Ratings are based on static sea level standard conditions of (dry) inlet air at 59° F. and 29.92 in Hg with no aircraft accessory drive or other loads. When applicable, indicate special test stand equipment used by the manufacturer for checking out new engines' performance.
Chap 1 Page 10 Par 8
5 June 1972 AC 33-2A NOTE 5. Model description - similarities, differences, and special characteristics.
RJ123 - Basic Model - Brief Description.
RJC123 - Similar to RJ123 Except List major differences.
NOTE 6. The following accessories are provided as part of the engine (or are optional) and comply with the aircraft installation requirements for aircraft.
NOTE 7. Model cancellations.
(b) Uncommon Notes Peculiar to Reciprocating Engines.
NOTE 8. Thrust - tractor or pusher.
NOTE 9. Horizontal or vertical installation - helicopter information.
NOTE 10. Center of gravity tabulation (if not shown in body of data sheet).
NOTE 1l. Vibration damper provision limitations.
NOTE 12. Manufacturers bulletins and instructions covering matters of special interest.
NOTE 13. Special ratings.
NOTE 14. Military models note.
NOTE 15. Special equipment.
NOTE 16. Other applicable notes.
(c) Uncommon Notes Peculiar to All Turbine Engines.
NOTE 8. Rotational velocities at standard and overspeed, alternate ratings, etc.
NOTE 9. Bleed air extraction.
NOTE 10. Alternate fuel information.
NOTE 11. Fuel or oil additives.
Chap 1 Par Page 11
AC 33-2A 5 June 1972 NOTE 12. Anti-icing, de-icing equipment, requirements.
NOTE 13. Power ratings for non-standard conditions.
NOTE 14. Rotor disk (Disc) integrity and rotor blade containment (where special provisions apply).
NOTE 15. Operational torques, power settings, and other special limits.
NOTE 16. Engine mount system.
NOTE 17. Power boost, injection.
NOTE 18. Other applicable notes for special equipment, etc.
(d) Notes peculiar to Turboprop Engines.
NOTE 19. Propellers - Model.
NOTE 20. Engine; Controls.
NOTE 21. Equivalent shaft hp. = Jet thrust 1b. + s.hp.
2.5
(e) Other notes peculiar to special conditions assigned.
C. model has become obsolete, e.g., if the type certificate holder Type Certificate Data Sheet (for obsolete engines). When an engine approval under the type certificate may be cancelled upon request. does not intend to manufacture it or any of its component parts, After cancellation, it is no longer necessary for the type certificate holder (former) to maintain up-to-date type design and type certificate data. engine will be revised to reflect the change in certification The type certificate data sheet of the status and when all models listed under one type certificate have been cancelled, the data sheet will then be transferred to a combined listing of obsolete engines. engines still in service is eligible to be continued under the status of the approval in effect at the time the certificate was The operation of obsolete cancelled. If reinstatement of the type certificate is desired by the former type certificate holder for the purpose of resuming active engine production, a new application for type certificate to be based on current FARS is needed. (Reference FAR, Sections 21.15, 21.21, 21.31, and 33.5) chap g Par Page 12
5 June 1972 AC 33-2A
9. DAIA REQUIRED. (Reference FAR, Sections 21.15, 21.21, 21.29, 21.31,
21.41, and Part 33.)
FAA Form 8110-12. Application for Type Certificate (OMB 04-R0078) is the form referred to in FAR, Section 21.15(a), and should be submitted to the FAA Regional Office of the region in which the applicant is officially located.
b. Preliminary Data. Certain technical data are needed for making the initial evaluation of conformity with the specific design requirements and the establishment of detailed qualification testing to be prescribed in accordance with FAR, Part 33. The data most useful for these purposes ínclude a preliminary type design description, technical design data which are required under FAR, Sections 21.21(b) and 21.29(a) (2), together with other useful background information. To facilitate this evaluation of engine design features, the preliminary data may be submitted along with the application for a type certificate. The following preliminary data are suggested:
(1) A preliminary model description, specification, or equivalent, containing the information called for in Appendices 1 and 2 as applicable and available to the applicant.
(2) Drawings showing external views and cross-sections of selected components reflecting unique and typical detailed features.
(3) A review of significant development history emphasizing the extent of development experience with the engine, with particular emphasis on unique or complex features or their combinations not hitherto used in aircraft engines.
(4) Proposals for substantiating compliance with the requirements of FAR, Part 33, for U.S. applicants' engines and Section 21.29 for import engines, by means of technical analyses or testing. Test proposals are desired appreciably before the proposed starting date of the test in sufficient detail to serve as a guide for testing, whereupon they may be incorporated in the type inspection authorization.
Final Type Design and Type Certificate Data for U.S. Manufactured Engines. Acceptable type design and type certificate data, test reports and computations data, required under FAR, Section 21.21(b), cover the engine design which completed the prescribed qualification testing. Acceptable data are described as follows:
Chap 1 Par 9 Page 13
AC 33-2A 5 June 1972
(1) Type Design Data. (FAR, Section 21.31)
(a) Engine Model Description. The final model description should provide data and information which is all officially verified to replace the preliminary model description.
(b) Engine Parts Drawings, Material, and Process Specifications. Acceptable data will show the configuration of the type design which successfully complied with the required tests and inspections.
A numerically arranged drawing list which shows the latest design change identification is recommended to accompany the drawings. Drawings should be sufficiently detailed to identify and completely describe the design features; supply information on dimensions, materials and processes necessary to define the structural strength of the product; part number location; and any other data necessary to allow, by comparison, the determination of the airworthiness of later products of the same type.
(2) Type Certificate Data (Ref. FAR, Sections 21.21(b), 21.41, and Part 33.)
(a) Test Reports and Computations. Test reports and computations to substantiate compliance with the applicable requirements of FAR Part 33. A test report should cover but not be limited to, the following:
1 Iest equipment a a complete description with photographs, or b reference to previous report in which same equipment was used.
c manner of engine mounting in the test equipment.
d calibration status of instruments.
1 Iest procedure a name of test, part of test sequence, or FAR Section.
b chronological log of testing.
c delays in tests and their causes.
Chap 1 Par 9 Page 14
• 5 June 1972 AC 33-2A d stops for minor corrections and servicing engine.
e time required for starts.
Test data a graphs showing variations in operating conditions during the endurance test.
b log sheets and calibration curves for calibration test data.
C method used in correcting test data to standard atmospheric conditions (Ref. Sections 33.45 and
33.85(a)) and substantiation of any correction factors used.
NOTE: All data should be legible, accurate data and, when plotted, use scales which are easily interpolated.
4 Teardown inspection.
a describe appearance of parts before assembly and after disassembly prior to cleaning for dimensional inspection.
b describe test results with before- and after-test tables of dimensions of major parts of the engine which are likely to incur wear or change of dimension.
c include photographs and descriptions of excessively worn parts.
d discuss any unusual wear, burning, overheating, part failure or impending failure, occurrence of heavy deposits on parts.
e indicate the condition of mating, sealing and friction surfaces, e.g., air-oil seals, each engine case, valve faces, piston rings, and oil seals.
1 Indicate the results of visual, X-ray, magnetic, fluorescent particle or other inspections of major parts.
AC 33-2A 5 June 1972 Laboratory analysis - of the types and grades of fuel, lubricants and hydraulic fluids used in the test - identify the specification to which the fluids conform.
b describe the condition of the lubricant and hydraulic fluids after the test.
(b) Instruction manual (S). (Ref. FAR, Section 33.5.)
The manual or manuals cover information for installing, operating: servicing: and maintaining the engine. The content of the manual or manuals is covered in paragraph 23 of this circular. Installation and operating manual data which have been substantiated, FAA approved, and are specifically required for engine approval in aircraft should be so indicated. For convenience, such data may appropriately be contained in a separate portion of the manual (s).
Type Design and Type Certificate Data for Import Engines. Certain technical data are required under FAR, Section 21.29(a) for import engines when a U.S. type certificate has been applied for.
The requirements for such import engines are based on reciprocal airworthiness agreements between the U.S. and the country of manufacture involved as indicated by FAR, Section 21.29. The airworthiness bases, and the exact extent and type of technical data to be supplied the FAA, for showing compliance with FAA requirements may vary in accordance with specific agreements between the Administrator and the Airworthiness Authority of the country of manufacture, but includes the usual application and preliminary data already covered, and usually the following:
(1) Type Design Data. Engine model description as discussed in paragraph c(1) of this section.
(2) Type Certificate Data.
(a) Certification compliance table.
(b) Engine manuals described in paragraph c(2) (b) of this section. If not included in the manuals, engine installation and general arrangement drawings are to be submitted in addition.
(c) Statement of compliance by the Airworthiness Authority of the country of manufacture, with the applicable airworthiness requirements.
Chap 1 Page 16 Par 9
5 June 1972 AC 33-2A
10. RESERVED.
11. INSTALLATION CONSIDERATIONS OF ENGINES. (FAR, Section 21.21.)
a . General. An engine type certificate may be obtained upon examination of the type design, completing all engine tests, and applying all applicable provisions of FAR, Part 33, and FAK, Section 21.21. While it is desirable that the engine applicant cater to all possible aircraft installation characteristics, this is not always possible because of the timing of and is not a requirement for engine certification. This does not obviate the desirability of intimately interrelated installation requirements being introduced into an engine certification program when the aircraft characteristics are known in sufficient time to do so. In this manner, new engines being developed concurrently with new aircraft may be expected to originally meet the applicable aircraft installation requirements. Otherwise, interrelated installations requirements may be met by either engine design changes or installation features. Such considerations are often specifically related to the engine-aircraft or engine-propeller combination under consideration and require evaluation either apart from or, at times, after engine certification may have been accomplished.
While it is usually obvious what data the aircraft applicant is responsible for when showing compliance with the aircraft installation requirements, there are occasions when the engine applicant's substantiation data may be utilized for this purpose. It is recommended, therefore, that at the initial engine type board meeting, the engine applicant establish the extent to which he plans to provide substantiation data for the installation. It then becomes desirable that such data be submitted with the engine type certificate data, for later coordination among FAA Regional Engineering and Manufacturing Offices. The foregoing procedure is for new engine models. Refer to Section 13 of this handbook for procedures for handling certain design changes to engines which may require changes to the installation. When components of the installation are provided as part of the engine type certification design (e.g., pumps, reversers, coolers, etc.), the engine type certificate data sheet should reflect this.
b. Effects of Typical Installation Features. Installation considerations include but are not limited to the following:
When the engine is used to drive a propeller, the engine vibration investigation must be conducted with a representative propeller as required by FAR, Section 33.43.
A satisfactory finding from the engine vibration survey will serve to permit certification of the engine, as far as its vibration is concerned. The installation, however, of the engine in an aircraft and the use of a different propeller, Chap i Par. 10 Page 17
AC 33-2A 5 June 1972 and metal propellers in particular, may require further vibration testing by the aircraft manufacturer for each installation undertaken. For engine vibration testing, use of a representative flight propeller is recommended as an acceptable means.
(2) A suggested way to take into account the effect of inlet design on turbine engine vibration is to conduct the vibration investigation required in FAR, Sections 33.63 and
33.83 using a representative inlet. Operation under air distortion conditions should identify safe limits for the engine. A finding of safe blade and associated engine stresses from such tests is sufficient for the purposes of engine certification. Comparison with the actual flight inlet characteristics will be made as in (3) following.
(3) Use of a bellmouth inlet and special exhaust nozzle is acceptable for endurance testing of turbine engines; however, to assure proper engine matching and minimize operation problems from air or gas flow variations, the flight type inlet and exhaust nozzle will be flight tested in meeting aircraft requirements to determine whether engine operating parameters and limits are being met when engine is operated in the aircraft. If the inlet or exhaust nozzle contains variable geometry features or integrated engine control features, more involved flight testing to verify the compatibility of the engine and such design features will normally be conducted in the prototype aircraft.
(4) Type testing of the engine will substantiate the maximum allowable temperatures of assemblies, components and fluids as required under FAR, Section 33.7. Installation in the prototype aircraft is checked as provided in the aircraft installation requirements to establish that these limits will not be exceeded in operation.
(5) Operating pressures are treated the same as temperatures in
(4) above and substantiated under FAR, Section 33.7. If the proposed installation of a piston engine imposes an exhaust back pressure significantly greater than that substantiated by type test, the higher pressure requires engine resubstantiation. Turbosuperchargers or mufflers may at times impose a back pressure greater than two inches of Hg.
which is considered appreciable. An acceptable means of complying with established back pressure limits would be to establish operating procedures which assure that the back pressure limits are not exceeded.
Chap 1 Page 18 Par 11
5 June 1972 AC 33-2A
(6) Helicopter drive systems may impose high vibration loads on engines. The vibration characteristics of the engineinstallation combination should be investigated for compatibility to determine whether established engine limits on vibration are exceeded.
(7) A type certificated engine may include some external lines, equipment mountings, diaphragms or firewalls which do not meet all certification requirements of some installations.
Added line shrouding, relocation or substantiation of fluid lines, or other changes constitute engine type design changes and may thus be required for the aircraft installation.
Such changes are accomplished preferably by the engine type certificate holder as approval based on engine compatibility and endurance qualification is usually necessary. However, upon achieving satisfactory coordination with the engine type certificate holder, accomplishment of such changes by the aircraft applicant is often acceptable as alternatives.
(8) With some engines, the engine type certificate holder or applicant may elect to incorporate items of equipment or accessories which are oftentimes handled as part of the aircraft installation responsibility. Examples of such items are engine mounted oil tanks, oil coolers, fuel heaters, generators, thrust reversers, inlet and exhaust nozzles, and various fluid pumps. When the engine manufacturer elects to furnish such accessories, it is basically implied that he will substantiate them for engine compatibility and be responsible for dealing with service difficulties. If the engine type certificate holder elects to establish aircraft installation compliance, he should develop and provide the necessary installation data in accordance with applicable aircraft requirements.
When considering the acceptability of using turbine engine bleed air for direct cabin air, the information called for in the model description regarding the extent of bleed air contaminants will be useful and should include the engine manufacturer's engine failure analysis results affecting bleed air contamínation.
12. RESERVED.
13. ENGINE CHANGES WHICH AFFECT INSTALLATIONS. (FAR, Sections 21.19 and
21.97)
a. This section discusses changes in design to certificated engine components whereby the engine operating limits, engine installation details, or airplane performance characteristics may possibly be altered significantly and require reinvestigation Chap Par 11 Page 19
AC 33-2A 5 June 1972 of the aircraft approval. Such enginc changes which are major are to be handled in accordance with FAR, Sections 21.19 and 21.97, for approval in the engine.
b. Extensive changes may result in engine model redesignation, and major changes of a lesser but significant degree may require revisions to limitations affecting data in type certificate datasheets, operating manuals and/or engine manuals. It is cautioned that seemingly slight changes in engine components may at times adversely affect aircraft performance and installation limitations. Some changes, which have resulted in certain problems, involve the engine fuel metering components for various engines and bleed air supply scheduling for turbine engines. For engine changes for incorporation in production engines and for general use, which are considered to possibly affect aircraft installations, the degree of compatibility with existing aircraft installations is first established.
This involves coordination by the FAA and the engine manufacturer with the responsible aircraft type certificate holder and suggested procedures are discussed in paragraph 13(c). If engine interchangeability is adversely affected for existing installations, it is desirable that either the engine or aircraft manufacturer initiate remedial modifications rather than establishing and qualifying a new model of engine. Engine type design changes should not be approved unless they are compatible with the aircraft installations in which the engine is being used as all engines of the same model designation should be interchangeable in the aircraft.
c. To assist the FAA in evaluating engine type design changes for effects on engine interchangeability in existing aircraft, it is suggested that the engine manufacturer coordinate the change with affected aircraft manufacturers. It is suggested also that the engine manufacturer establish a written procedure whereby he will notify the FAA engine controlling region of the results when he has completed coordination of each affected engine change.
Accomplishment of these steps should reasonably assure thorough evaluation of each design change and expedite its approval on the aircraft. If any doubt remains concerning the compatibility status of an engine change, its status should be resolved between the FAA engine and aircraft controlling regions.
14. RESERVED.
15. OFFICIAL ENGINE TESTS. (FAR, Section 21.33, and Part 33.)
Official engine certification tests are to be conducted in accordance with the authorization directed to the applicant.
The tests required for engine certification are as prescribed by pertinent sections of FAR, Part 33. The authorization may be a letter or a type inspection authorization (FAA Form 316).
Chap 1 Page 20 Par 13
5 June 1972 AC 33-2A The latter is used to request participation of representatives from other than the cognizant propulsion engineering office.
b. Witnessing of tests by FAA representatives as prescribed in FAR, Section 21.33, is accomplished at least for the engine calibration, endurance, and operation tests, and the teardown inspection following these tests. Federal Aviation Administration representatives may also witness such specialized tests as vibration measurement, detonation, rotor integrity, rotor blade containment, icing, and ingestion tests. The engine manufacturer's designated engineering representative should witness all certification testing and subsequent parts improvement tests, conducted by the manufacturer, for the purpose of authenticating the tests and the results.
c. The test authorization identifies the following details relating to official tests:
(1) The engine to be tested and the specific tests with the schedule of runs and test limits to be employed.
(2) The test equipment to be utilized.
The test witnessing desired.
(4) Inspections to be conducted, covering both the engine and the test equipment as appropriate.
16. RESERVED.
17. APPROVAL OF ENGINE PARTS AND MATERIALS. (FAR, Sections 21.19, 21.113,
21.303, and Part 33.)
a. General. All engine parts and materials which have met the design and test requirements of FAR, Part 33, for engine type certification are eligible to be approved parts.
b. Changes by Type Certificate Holder. Changes to the type design of the engine may be made by and approval granted the type certificate holder when he meets the requirements prescribed under FAR, Part 33, and Part 21, Subpart D, discussed in Section 19 of this handbook. As indicated for major changes, the parts should undergo testing similar to the original substantiation unless alternate acceptable substantiation is provided. Minor changes do not usually require testing for their substantiation. Experience has indicated that the cumulative effects of both major and minor changes, especially when groups of new changes are incorporated in production engines, may have significant adverse effects on safety or durability.
Chap 1 Par 15 Page 21