ARC Will Revisit The "51-Percent" Rule

With the advent of new fabrication techniques and manufacturer-supported "builder-assist" programs, one could argue the definition of an "amateur-built" aircraft isn't what it used to be.

On Friday, the FAA posted notice in the Federal Register that, until further notice, the agency's Aircraft Certification Service has suspended courtesy inspections of aircraft kits for "amateur-built" status. The purpose of these evaluations was to indicate if a prefabricated amateur-built aircraft kit could be eligible for certification as an amateur-built aircraft.

The Federal Aviation Administration (FAA) Aircraft Certification Service established an Amateur-Built Aviation Rulemaking Committee (ARC) on July 26, 2006. The ARC was made up of representatives from the FAA, aircraft kit manufacturers, commercial assistance center owners, and associations. The purpose of the ARC was to make recommendations regarding the use of builder or commercial assistance when fabricating and assembling amateur-built aircraft under FAR 21.191(g) -- the so-called "51 percent" rule.

FAR 21.191(g) defines an amateur-built aircraft as "an aircraft the major portion of which has been fabricated and assembled by persons who undertook the construction project solely for their own education or recreation." In essence, that means for an aircraft to be declared as amateur-built, the builder must complete construction on the majority of the aircraft's components themselves -- without undue assistance from the kit's manufacturer.

That rule -- or, at least, the spirit of it -- wasn't in dispute when most 'homebuilt' planes were, in fact, completed in the builder's home, hangar, or garage... fabricated from raw materials or a finite number of preassembled components, from a set of plans. In recent years, however -- particularly with the onset of composite construction -- several kit manufacturers started shipping "quick-build" kits, with major subassemblies already fashioned.

Many of those kitmakers also launched builder assistance programs. Some even allow the builder access to a professional facility in which to complete their aircraft, all the tools they need, and assistance from company representatives. The aircraft themselves have also become far more advanced -- with companies offering 'homebuilt' high-performance, pressurized turboprops and even jets, that frankly couldn't be completed without some assistance from professionals.

Those companies maintain their programs are in keeping with the 51 percent rule, as builders still must complete the majority of assembly to the aircraft. However, the ARC has since concluded the current FAA Directives and Advisory Circulars are no longer adequate.

"Current technologies that allow for the fabrication and assembly of sophisticated amateur-built aircraft were not envisioned at the time § 21.191(g) was promulgated or when the current forms and methodology were developed," the agency states. "Most amateur-built aircraft kits were generally simple to fabricate and assemble and did not require commercial builder assistance. FAA has provided the aforementioned amateur-built kit evaluations in response to manufacturer’s requests to determine if the percentage of the kit completed by the manufacturer would leave the major portion (51%) of the work to be completed by the amateur-builder.

"These evaluations are not a regulatory requirement," the agency adds. "Rather, these evaluations have been a courtesy that FAA has provided for the convenience of the kit manufacturers, their customers, and FAA Inspectors. These evaluations have allowed the FAA to pre-evaluate amateur-built kits to determine (when built according to the manufacturer’s instructions) if the kits could be eligible for an Experimental Airworthiness Certificate under 14 CFR Part 21 § 21.191, Experimental Certificates. When a kit has been found to be eligible, it is added to the FAA’s kit listing, which is available via the internet to prospective buyers. These kit evaluations inform prospective applicants that they could be eligible for an experimental amateur-built airworthiness certificate if they completed their aircraft in compliance with the FAA-evaluated assembly and instruction manuals and fabricated and constructed the aircraft in compliance with 14 CFR part 21, § 21.191(g). The method of determining what constitutes the major portion of construction has undergone several changes since the rule was first codified."

The FAA also notes manufacturers offering assistance have allowed amateur-builders to "share credit" for assembly of components with the manufacturer -- a loophole the agency says must be revisited.

"When FAA staff developed the commonly used form 8000–38, "Fabrication and Assembly Operation Checklist", to calculate major portion, the intent was that a single check mark in a column on the form would identify who did the task," the agency states. "Some manufacturers and FAA representatives calculate major portion by using a "task-based" accounting mechanism that incorporates a "dual-check" system whereby an amateur-builder may be given shared credit even if that person does not complete 50% of the task. When this is used in practice, the kit manufacturer and amateur-builder share credit on the Form 8000–38.

"It was not envisioned that credit for a task would be offered to an amateur-builder simply assisting in the fabrication and assembly, as is happening today in some cases," the FAA concludes.

The FAA plans to resume amateur-built kit evaluations after issuing final policy changes. Prior to publishing the final policy, FAA will solicit comments on draft policy, internal orders and advisory circulars through a notice in the Federal Register.

The agency stressed that while kit evaluations have been suspended, amateur-built kit manufacturers may continue to develop, manufacture, market and sell their aircraft kits. Airworthiness certifications conducted by the FAA in response to requests from amateur-builders for their individually fabricated and constructed aircraft will continue.

FMI: www.faa.gov, www.dot.gov