3.2.4 Prepare the Data Package. To organize project data and standardize the field approval process, we recommend using a data package. A typical data package might include the following items:
1. Field approval checklist;
2. Copies of any substantiating data;
3. FAA Form 337, Major Repair or Alteration (Airframe, Powerplant, Propeller, or Appliance);
4. Compliance checklist;
5. Maintenance information; and
6. Draft proposed AFMS or RFMS.
Note: Review and approval of an AFMS, RFMS, or SAFM is independent of the review and acceptance of approved data (or approval of technical data). The approval is indicated on the AFMS, RFMS, or SAFM, so you do not need a separate FAA Form 337. See paragraph 4 for further AFMS information.
3.2.4.1 Complete the Field Approval Checklist (recommended). The checklist and instructions in Appendix A can be used to organize data and information before requesting a field approval. It is a tool to ensure your submission is complete.
3.2.4.2 Substantiate Applicable Requirements. Indicate the specific applicable airworthiness requirements to show compliance, including the amendment level of the regulation and other requirements, except that you should not use general references, such as “part 25.” As shown in Appendix B, Instructions for Completing the Compliance Checklist, you may reference a compliance checklist specific to descriptive data instead of listing regulatory requirements.
3.2.4.3 Complete FAA Form 337. Complete FAA Form 337, except for dates and signatures in blocks 6 and 7. You should enter dated signatures after completing the repair/alteration and inspecting for conformance. AC 43.9-1, Instructions for Completion of FAA Form 337, provides guidance on how to complete this form.
3.3 Evaluate the Data. Review the data to determine (1) if the package is complete and inclusive, and (2) if applicable data has been approved. There are several methods to obtain all the approved data. We sometimes use the field approval process, with an authorized ASI, to approve technical data. Another alternative is approval of all the data by a DER or ODA. In some cases, you might need multiple DERs when the repair/alteration deals with several disciplines, such as systems and structures.
3.3.1 The Field Approval Process. Field approvals are a method by which the FAA approves technical data for a major repair/major alteration on a single aircraft and gives operational approval by reviewing and approving an AFMS (RFMS or SAFM). A field approval may
10 constitute an approval for the alteration or repair and is a one-time approval for the product or appliance to which it applies. The overall process is illustrated in Figure 3-1, Field Approval Process, and is explained in paragraphs 3.3.1.1 through 3.3.1.3 below.
Field approvals are a method by which we approve technical data for a major repair/major alteration on a single aircraft.
A field approval may require engineering assistance or coordination with an AIR Certification Branch. You may use the field approval process to obtain approval of acceptable data in certain cases.
Note 1: The information and process steps are provided in Figure 3-1 in a specific order to show a logical progression through the repair/alteration. We are not implying that one step must follow another in the order presented. Several actions may take place concurrently or in a different order. The goal is that you address all necessary concerns and regulatory considerations when performing a major repair/major alteration.
Note 2: The paragraph numbers next to blocks in the figure correspond to associated paragraph numbers in this order, which provide information in more detail.
3.3.1.1 Contact the ASI. Contact a local FAA office and speak with an ASI who has field approval authority. Discuss the repair or alteration with the ASI and determine if you need to meet to review the request. Be as specific as possible about the needs, and especially about the schedule. In some cases, you may contact DARs delegated with the authority to perform data approvals in support of a major repair or alteration.
3.3.1.2 Provide Data Package to the ASI. Send a complete data package to the ASI.
Using the checklist in Appendix B is one way to organize data and may help prevent omissions.
3.3.1.3 ASI Review Procedures.
3.3.1.3.1 When the ASI receives the package, the ASI will review it to determine if the field approval request is appropriate.
1. Confirm that the applicant, in accordance with 14 CFR § 1.1 and part 43 appendix A, properly determined that the repair or alteration is major.
Minor alterations/repairs do not require approved data. ASIs who deny data approval requests for alterations or repairs that do not require approval must explain to the applicant the reason for the denial and, if requested, provide a written explanation in letter or electronic form.
2. Once the repair/alteration is confirmed to be a major, the ASI or designee should refer to the MRADA Job Aid in order to confirm that the project is within the scope of a field approval. The ASI should examine the data and
11 determine if all the data for the project has been approved. If all the required data is approved, then a field approval or STC is not required.
3. If all the required technical data is not approved, then additional approvals
(e.g., DER-approved data) or a field approval are necessary. If it is determined that the alteration requires an STC, inform the applicant to apply for an STC or amended TC (if the applicant is the design approval holder (DAH)).
3.3.1.3.2 After the ASI has reviewed the data package and/or inspected the aircraft, and can approve the repair/alteration, the ASI may (1) approve the data package only, or (2) approve the repair/alteration on FAA Form 337 by physical inspection. The ASI will sign and date block 3 indicating approval. The ASI enters one of two statements:
1. First statement: “The data identified herein complies with the applicable airworthiness requirements and is approved for the above-described aircraft, subject to conformity inspection by a person authorized in § 43.7.”
Note: This statement is entered on block 3 of FAA Form 337 when the ASI reviews a data package and completes data approval.
2. Second statement: “Approval by Physical Inspection, Demonstration, Testing, etc. One Aircraft: The repair or alteration identified herein complies with the applicable airworthiness requirements and is approved for the above-described aircraft, subject to conformity inspection by a person authorized in § 43.7.”
Note: This statement is entered on block 3 of FAA Form 337 when the ASI makes a physical inspection of the aircraft, or the applicant satisfactorily performs a demonstration or other type of test and the ASI completes an installation or repair approval.
3.3.2 DER Data Approval.
3.3.2.1 A properly authorized DER is a designee of the FAA whom an applicant may employ to provide approved technical data to support a major repair/major alteration. A DER’s authority is limited to specific functions, and data from more than one DER may be necessary. If an applicant has determined that a single DER has, or multiple DERs have, provided necessary approved data for the repair/alteration before involving the ASI, then no field approval is required.
3.3.2.2 A DER may approve descriptive and/or substantiating data, if specifically authorized, to support a major repair or major alteration. However, this DER-approved data may not be adequate to cover every aspect of the repair or alteration. Repairs or alterations involving flight manual supplements, ALs,
12 ground and flight test plans, ground and flight tests, compliance inspections, alterations to critical structure or life-limited parts, ICA, special conditions, noise findings, and ELOS findings may require data that a DER is not normally authorized to approve. If the repair or alteration requires approval of data beyond the DER’s authority, then additional approval, such as an FAA field approval or managing office approval, is required.
3.3.2.3 In order to help the repair or alteration installer, DERs will provide a statement on their approval to indicate whether the data being approved does (or does not) constitute all the data necessary to substantiate compliance of the repair or alteration with all applicable airworthiness regulations. In order to help the installer and Flight Standards District Office (FSDO) involved, the DER must add the following note to the “List of Data” block on FAA Form 8110-3, Determination of Compliance with Airworthiness Standards:
“This approval is for engineering design data only. It indicates the data listed above demonstrates compliance only with the regulations specified by paragraph and subparagraph listed below as ‘Applicable Requirements.’ This form (does/does not) approve all data necessary for the installer to reference in the approval for return to service.”
3.3.2.4 We have referenced DER authorizations and limitations in FAA Order 8110.37, Designated Engineering Representative (DER) Handbook.
This reference includes Repair Specification DER (RS-DER) authorizations and limitations, and general guidance on approving data for major repairs/major alterations. A list of current DERs and their appointed functions and authorizations is available at https://www.faa.gov/other_visit/aviation_ind ustry/designees_delegations/find_designees.
Note: Although DERs are not authorized to approve block 3 of FAA Form 337, you may use DER-approved data as a basis for a repair/alteration in support of FAA Form 337. However, when you have obtained sufficient DER-approved data that addresses requirements in 14 CFR parts 21 and 43, the approval process applicable to the alteration is complete. The person performing the alteration, not the DER, is then responsible for a conformity inspection and for return to service approval of the installation.
3.3.3 ODA Data Approval. You may employ an ODA holder to provide approved technical data to support a major repair/major alteration. If the applicant employs a DER or ODA to provide approved technical data to support a major repair or major alteration, then the applicant is responsible for ensuring that the DER or ODA is authorized to approve such technical data, as applicable to the repair or alteration. If the data, as approved, addresses the entire repair or alteration, and all of the requirements of 14 CFR parts 21 and 43 are met, there is no requirement for any further approval by the ASI. If the repair or alteration
13 data is approved solely by the DER, ODA, or DAR, but necessitates maintenance instructions, the maintenance instructions should be prepared by the applicant and recorded in block 8 of FAA Form 337.
3.3.3.1 TC/STC ODA Holder With Specific Authority. A TC/STC ODA holder with specific authority for major repairs/major alterations may approve data within its authority and limitations. The data approved by an ODA holder may not adequately cover every aspect of the repair/alteration.
1. If a major repair, alteration, and airworthiness (MRA) ODA holder approves all aspects of the major repair/major alteration data, then no field approval is necessary.
2. If an MRA ODA holder (or holders) does not approve all aspects of the major repair/major alteration data, then a field approval is necessary.
3.3.3.2 ODA Authorizations and Limitations. For ODA authorizations and limitations and general guidance on approving data for major repairs/major alterations, refer to FAA Order 8100.15, Organization Designation Authorization Procedures. A list of authorized ODA holders is available on the FAA Designees and Delegations web page: https://www.faa.gov/other_vis it/aviation_industry/designees_delegations/find_designees/oda-directory.
Note: The person performing the alteration, not the ODA, conforms and approves the installation from ODA-approved data. ODA data does not constitute a field approval, but is approved data that, like other approved data, can be used for major repairs/major alterations without further approval if the data addresses the entire repair/alteration. In this case, the applicant does not need to request a field approval.
3.4 Perform Repair or Alteration. After the repair or alteration data is approved, an applicant can alter or repair the aircraft or one of its components. When the work is complete, you should review the requirements of 14 CFR § 91.407 and determine if a flight check is required. Complete FAA Form 337 and follow procedures in 14 CFR part 43 appendix B.
Figure 3-1. Field Approval Process Applicant determines need for repair or alteration
3.2.1 Is this a Repair repair or alteration?
Alteration Is the scope of the alteration sufficient to process as a No major change in type design?
(14 CFR § 21.93) 3.2.2.3 Consider as a mino Applicant performs See repair or alteration and Figure 3-2 repair of minor documents in alteration maintenance records Yes 3.2.2.1 Consider as a major Does change in type design additional data No No field approva need to be required approved? 3.3 Applicant applies for Yes STC or TC amendment Applicant prepares After FAA approves data pacakage STC or TC amendment, applicant performs Applicant may make repair or alteration and records it per 14 CFR Applicant submits dat package to FAA ASI 3.3.1.2 necessary corrections and resubmit part 43 appendix B No ASI notifies FAA approves data package? applicant in writing
3.3.1.3.2 Yes ASI approves data and signs block 3 of FAA Form 337
3.3.1.3.2 Applicant performs repair or alteration and records it per 14 CFR part 43 appendix B
3.4 Aircraft is returned to service 14
Figure 3-2. Determination of Major or Minor Alteration or Repair From Figure 3-1 Repair or alteration listed in Yes To product's Figure 3-1 specifications?
To No Figure 3-1 Could the repair or alteration have an practices or Accepted No appreciable affect on elementary operations?
Yes Yes Weight? If Repair improperly No Repair or done would Yes alteration? appreciably affect airworthiness?
Yes Balance?
Alteration No No Structural Yes strength?
No Yes Performance?
No Powerplant Yes operation?
No Flight Yes characteristics?
No Other qualities affecting Yes airworthiness?
No 15
16 4 FLIGHT MANUAL SUPPLEMENTS.
4.1 General Information. Alterations that result in a change to limitations, procedures, performance, or loading information from a current Aircraft Flight Manual (AFM) or placards, require an applicant to develop revised or supplemental information as addressed in paragraph 4.3.
4.2 AFMs. Aircraft operating procedures and performance limitations are typically provided as:
1. AFMs, including either Airplane Flight Manuals or RFMs;
2. Markings or placards; or
3. Combinations of the above.
4.3 Manual Supplements. Supplemental information should be provided by one of the following methods:
1. If the aircraft has an AFM, the supplemental information must appear in an AFMS or RFMS. Refer to 14 CFR § 23.2620(a).
2. If the aircraft does not have an AFM, the applicant should create an SAFM so necessary information is available to the pilot. An SAFM complements a pilot’s operating handbook (POH), which may not have specific FAA approval. Procedures for creating and approving an SAFM are the same as those for an AFMS.
3. You may present the supplemental information either as modified, or as additional markings and placards in aircraft type certificated before AFMs were required.
4.3.1 If you substantiate a major alteration based on data from a previous approval, you must include a flight manual supplement if the previous approval had one. For the purposes of this guidance, AFMSs include RFMSs and SAFMs, as well. Refer to 14 CFR § 23.2620.
4.4 Format and Content. The AFMS or placards must contain any new or changed limitations, emergency or abnormal operating procedures, normal operating procedures, performance, and system operating instructions. The supplement should be consistent with the format of the basic AFM and must be applicable to the specific installation configuration for the installed equipment and systems. ASI approvals of AFMSs should not contain conditional operation descriptions and need to be explicit for the configuration of the targeted aircraft. AC 23-8, Flight Test Guide for Certification of Part 23 Airplanes, and AC 25.1581-1, Airplane Flight Manual, provide guidance on what is recommended in an AFMS for aircraft. Refer to 14 CFR §§ 23.2610 and 23.2620.
4.4.1 The AFMS should include:
1. The aircraft manufacturer’s name;
2. Model number;
3. Serial number; and
4. Registration number.
4.4.2 You should include the following information, as applicable to the altered conditions:
1. Abnormal or emergency procedures;
2. Normal operating procedures;
3. Aircraft performance;
4. Aircraft Weight and Balance (W&B); and
5. Loading information.
4.4.3 You must install placards in clear view of the pilot and, as applicable, in proximity to affected equipment. Refer to 14 CFR § 25.1541, § 27.1541, or § 29.1541.
4.5 Supplement Information Approval. Responsibility for approval of the supplement (including placards) depends on the supplement type.
1. Alterations that change the operating limits of the aircraft, aircraft engine, or propeller would require coordination with an appropriate AIR Certification Branch for approval of the supplement or placard that stipulates limitations to the operation of the aircraft.
See paragraph 4.6 for details.
2. ASIs with field approval authorization, and (1) authorized specifically by Flight Standards (FS) policy, or (2) are delegated by an AIR Certification Branch to review and approve certain AFMSs.
3. An authorized DER/ODA can approve an AFMS or placards.
4.5.1 Repairs or alterations that do not result in a change to limitations, procedures, performance, or loading information may not require a supplement, or the supplemental information may consist of system operating instructions only.
4.5.2 An ASI with field approval authorization may review and grant field approval of an appropriately affixed placard characterizing operating limitations or information about certain equipment and systems. Refer to 14 CFR § 25.1541, § 27.1541, or § 29.1541. For examples of such placards—“Not For IFR” or “VFR Only”—refer to the “Kinds of Operations” paragraph in 14 CFR § 25.1525, § 27.1525, or § 29.1525.
4.6 AIR Certification Branch Approval Process.
1. If an ASI or designee is not authorized to approve the AFMS, the ASI must forward the alteration data package, including proposed AFMS, to the AIR Certification Branch.
2. The ASI may route the AFMS to AIR Certification Branch flight-test personnel for review.
3. After review and approval of the AFMS/RFMS/SAFM or limitations placard, the applicant should record the approval date, document name, and number on FAA Form 337, Block 8, Description of Work Accomplished. Indicate on such entries that the AFMS/RFMS/SAFM is inserted or affixed to the AFM or POH. Refer to 14 CFR § 43.9 and part 43 appendix B, and AC 43.9-1.
4. The ASI will advise you that equipment upgrades, such as changes to the operating system software or hardware, may invalidate the existing FAA-approved AFMS and trigger a subsequent review and approval of the AFMS.
4.7 Additional AFMS Considerations.
4.7.1 Operating procedures for a newly installed appliance or system are frequently provided in an AFMS. Alternatively, you may incorporate equipment manufacturer operating manuals by reference into the AFMS.
4.7.2 Manufacturer operating instructions included/referenced in the AFMS for systems or equipment, such as those for navigation systems, do not require specific approval, but if included in an AFMS, the AFMS itself must be approved. Refer to 14 CFR § 23.2620.
4.7.3 If all of the following conditions are met, an AFMS is not required (refer to 14 CFR § 23.2620):
1. Does not restrict, displace, or limit the use of required equipment;
2. All new limitations can be addressed via placards;
3. The aircraft performance is not negatively affected;
4. Does not require a placard per TC or STC;
5. Visual flight rules (VFR) use only; and
6. Is nonrequired equipment.
4.7.4 For equipment limited to VFR, you must install a readable placard, in clear view of the pilot, stating that the equipment is only for VFR operations. If the equipment automatically displays this message on start-up and the pilot must clear the message, an AFMS or RFMS is unnecessary, since the placard or display contains the equipment limitation. Refer to 14 CFR § 23.2610.
5 MAINTENANCE INFORMATION.
5.1 Purpose of Maintenance Information for a Major Repair or Major Alteration.
Maintenance information provides adequate instructions to maintain the repaired or altered product in an airworthy condition. For this AC, major repair and major alteration maintenance information can include:
1. Additional maintenance instructions;
2. Supplemental information for the product’s maintenance manual or Illustrated Parts Catalog (IPC);
3. Supplemental information for the product’s ICAs;
4. Supplemental information for articles or appliance maintenance manuals or IPC; and
5. Any other information required to maintain the product in an airworthy condition.
5.2 Benefits of Providing Maintenance Information for a Major Repair or Major Alteration.
5.2.1 When the owner/operator references maintenance information in block 8 of FAA Form 337, this gives the aircraft owner or operator the following advantages:
1. One document can reference or contain maintenance information about a major repair/major alteration;
2. The maintenance information becomes a permanent aircraft record as required by 14 CFR § 91.417(a)(2)(vi); and
3. The owner or operator can contact the FAA registry for a replacement FAA Form 337 if the maintenance information is lost or destroyed.
Note: The owner or operator may also forward a previously completed FAA Form 337 and associated maintenance information if the FAA Form 337 is not currently in the registry.
5.2.2 The additional reference to maintenance information as part of a major repair/major alteration in the aircraft’s maintenance entry will ensure that maintenance personnel appropriately address maintenance of the major repair/major alteration during future inspections.
5.3 Maintenance Information as Part of the Major Repair or Major Alteration Data Package. The FAA has determined that, as per 14 CFR § 21.50, a major repair/major alteration data package must address how the major repair or major alteration affects continued airworthiness. You must develop maintenance information if a major repair/major alteration affects the continued airworthiness, or must also state that a major repair or major alteration does not affect continued airworthiness. If a major repair or major alteration affects the Airworthiness Limitations Section (ALS) of the ICA or a part of the ICA that requires FAA approval, such as described in 14 CFR part 26 ICA requirements, approval of maintenance information for the major repair or major alteration comes from an AIR Certification Branch/ODA. The maintenance information checklist is a guide for an applicant to develop maintenance information using methods, techniques, and practices acceptable to the FAA. See Figure 5-1, Major Repair or Major Alteration Maintenance Information Checklist.
5.4 Maintenance Information Under the Civil Air Regulations (CAR). For field-approved major alterations to CAR-certificated aircraft, engines, and propellers, maintenance information must meet the requirements of the original certification basis. In cases where the major alteration adds new items the CAR requirements did not address, the major alteration must meet applicable 14 CFR requirements. Figure 5-1 lists acceptable
20 guidance for these installations, and for inspections not covered by the Original Equipment Manufacturer (OEM) instructions.
5.5 Maintenance Information Development.
5.5.1 Major alterations needing maintenance or inspections not covered by the OEM instructions must have maintenance information prepared in accordance with methods, techniques, and practices acceptable to the FAA, as required by 14 CFR § 43.13. The applicant should reference maintenance information as an attachment on block 8 of FAA Form 337. The entry, required by 14 CFR § 43.9, must refer to the maintenance information and be identified by the approval date of the FAA Form 337, as per 14 CFR §§ 43.5 and 43.11. The applicant must keep the form in the aircraft’s permanent records per 14 CFR § 91.417(a)(2)(vi). Refer to AC 43.9-1. Maintenance information referenced in block 8 of FAA Form 337 is considered acceptable to the FAA and will not be approved unless specifically required by regulation, as with changes to the ALS or 14 CFR part 26 requirements. Applicants should use Figure 5-1 as a guide to help ensure they meet all applicable requirements.
Note: Maintenance information is required to be acceptable to the FAA, as per 14 CFR §§ 43.9 and 43.13; therefore, it should be referenced as a separate document on block 8 of FAA Form 337. Block 8 of FAA Form 337 is for data that is approved by the FAA.
5.5.2 If the repair or alteration data is approved solely by the DER, ODA, or Designated Airworthiness Representative (DAR), but necessitates maintenance instructions, the maintenance instructions should be prepared by the applicant and referenced in block 8 of FAA Form 337.
5.6 Maintenance Information Content. Refer generally to the relevant appendices to 14 CFR parts 23, 25, 27, 29, 31, 33, and 35 addressing ICA. Maintenance information must include specific instructions describing how to maintain affected areas for continued airworthiness, as per 14 CFR § 43.13. For example, maintenance information might include a new requirement for a special inspection during 100-hour or annual inspections.
Such maintenance information must also include installed appliances that may impact maintainability of the product, or require periodic maintenance to ensure continued performance. When appropriate, maintenance information must also include specific instructions for determining excessive wear, distortion, or deterioration; troubleshooting information; and installation and removal procedures, including operational checks, as per 14 CFR part 43 appendix D. You must also include servicing requirements, as per 14 CFR part 43 appendix A, such as recommended fluid change intervals or lubrication schedules. In the instances that a repair/alteration must meet 14 CFR part 26 requirements, only the AIR Certification Branch may approve the maintenance information developed. The maintenance information must contain:
1. Inspection tasks and task intervals;
2. Instructions and procedures in the aircraft maintenance manual to accomplish the tasks; and