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Field Approval Process

The field approval process is used for one serial numbered aircraft in accordance with FAA Order 8900.1, Vol. 4, Chapter 9.

Steps of the field approval process

  • The applicant proposes to repair or alter one serial numbered aircraft.
    • The applicant must determine that the change is a major alteration or repair per 14 CFR 1.1 and 14 CFR part 43, Appendix A;
  • The change is annotated on a FAA Form 337, Major Repair and Alteration;
  • The applicant submits FAA Form 337 annotating the change with the data package to the Flight Standards District Office;
  • The Flight Standards District Office may meet to assess the scope, complexity of change in light of 14 CFR 1.1 definitions and 14 CFR part 43, Appendix A. The Flight Standards District Office determines that either:
    • The data is adequate and no field approval is required.
    • The Aviation Safety Inspector can sign Block 3 of FAA Form 337 to approve the repair or alteration, or
    • Additional data from the applicant is needed if the original data package is found to be inadequate, or
    • The data needs Aircraft Certification Office review in light of its complexity or adequacy, or
    • The alteration is of a type listed in FAA Order 8900.1 which exceed the basic scope of a Field Approval and must be processed as an STC.
  • If the Aircraft Certification Office reviews the data, they may:
    • Determine that the data package is acceptable as is and can be approved as a Field Approval;
    • Support the field approval with engineering review, advocate additional data or testing, assist with the flight test and Airplane Flight Manual supplements;
    • Recommend that the project should be an Aircraft Certification Office managed Supplemental Type Certification project, and should proceed with the Supplemental Type Certification process.
  • The Inspector approves the repair or alteration by signing block 3 of Form 337.
  • Owners, operators, and persons who repair or alter aircraft, FAA Flight Standards Inspectors, FAA Aircraft Certification Office Engineers, and DERs need to know when a field approval is made.

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