Builders often use parts, assemblies, and components from type-certificated (TC) aircraft on their homebuilt. In fact, some homebuilt aircraft are specifically designed to include TC aircraft components. For example, Breezy plans do not include wing drawings because the aircraft was designed to use surplus Piper Super Cruiser wings. This is fine, to a point, but the builder should be aware of the impact this might have on licensing the project. In order to be eligible for certification in the experimental/amateur-built category, the aircraft must meet certain criteria set forth by the FAA, and extensive use of TC parts might jeopardize this amateur-built status. In order to understand how the use of TC parts might impact a homebuilt project, we must first take a look at how the FAA defines an amateur-built aircraft.
Amateur-built aircraft are “aircraft in which the major portion has been fabricated and assembled by a person(s) who undertook the construction process solely for their own education or recreation.” The term “major portion” is key, and the FAA has defined this as “when the aircraft is completed, the majority of the fabrication and assembly tasks have been performed by the amateur builder(s).” Note that the FAA considers only the tasks completed, not the time spent working on the project.
FAA inspectors use FAA Order 8130.2 for guidance when inspecting and licensing amateur-built aircraft. This document includes FAA Form 8000-38, FABRICATION ASSEMBLY OPERATION CHECKLIST, which lists the tasks to be considered by the FAA when determining whether a builder has met the major portion requirement. Order 8130.2 states that, while parts and components from TC aircraft can be used, so long as they are in a condition for safe operation, no credit for fabrication and assembly will be given to the amateur builder for these parts. Thus, if you use too many TC parts or components in your aircraft, you will not have completed enough tasks to constitute the major portion, and the aircraft will not qualify for amateur-built category. (See Advisory Circular 20-139 for the FAA’s list of tasks).
EAA gets several calls a year from members who are thinking about rebuilding a certificated aircraft with the idea that, if they do enough work on the aircraft it might qualify for amateur-built status. However, as previously discussed, the disassembly and reassembly of TC parts does not count toward qualification for amateur-built status, so the rebuilding or restoration of a TC aircraft will not meet the requirements for issuance of an experimental/amateur-built airworthiness certificate.
There have been cases where people have made major modifications to a TC aircraft and have attempted to license the aircraft as an experimental/amateur-built. However, these aircraft do not meet the requirements for amateur-built status, so these people have had to spend a significant amount of money and time working with an A&P/IA to re-license the aircraft in standard category, or place it in the more restrictive experimental/exhibition category. It is FAA policy that experimental certification should be used for certain specific purposes, and is not to be used as a way around type certification, Airworthiness Directives (AD’s), Supplemental Type Certificates (STC's) and field approvals.
When considering the incorporation of parts or components from TC aircraft into your homebuilt, or contemplating the modification or restoration of a TC aircraft, it would be wise to contact your local FAA Flight Standards District Office (FSDO) or Manufacturing Inspection District Office (MIDO) and discuss your plans with the airworthiness inspectors before you begin. It’s better to lay the groundwork for certification ahead of time, rather than getting an unpleasant surprise after you’ve put a good deal of time and money into the project.
For more information on certification of amateur-built aircraft, contact EAA Aviation Information Services at 888-322-4636, or e-mail firstname.lastname@example.org.