U.S. Department
of Transportation

Federal Aviation

St. Louis
Flight Standards District Office

10801 Pear Tree Lane
Suite 200
St. Ann, Missouri 63074


January 2005




Thought for the month.....
We should remember the old Falstaff Beer slogan - "Same as it ever was".

AD's and Amateur-Built Aircraft... Noncompliance with an airworthiness directive (AD) can make operating an aircraft or an aircraft product in conflict with Part 39 of the Federal Aviation Regulations. As aircraft owners, renters, or mechanics it is necessary for us to know how the FAA interprets the way this regulation is applied and get a better understanding of Part 39.

Section 39.3 states: "FAA's airworthiness directives are legally enforceable rules that apply to the following products: aircraft, aircraft engines, propellers, and appliances." The definitions of many words used in the FAA's terminology are in Part 1. Unfortunately the word product isn't there. This can be important when word wrestling with the FAA's legal council. In Part 21, the Part that establishes the standards for manufacturing aviation parts and products, the word "product" is defined to comprise an aircraft, aircraft engine, or propeller. In this discussion we will focus on engines and propellers only and guidance that addresses the FAA's position on compliance.

Two schools of thought exist pertaining to the requirement to comply with AD's on experimental amateur-built aircraft. One says that AD's do not apply to experimental amateur-built aircraft, conversely the other school of thought says AD's on type certificated products, regardless of their application, do apply and must be complied with.

Amateur-built aircraft are not a type-certificated product. But, some amateur-built aircraft have type certificated engines and propellers installed in them. Section 39.3 includes [type certificated] aircraft engines and propellers. When application for an airworthiness certificate is made the applicant has to list the installed engine(s) and propeller(s). The application, FAA form 8130-6, is a legal document. Any information on the application was checked and confirmed by the authorized person who issued the airworthiness certificate. It can be argued that if a type certificated engine or propeller was listed on the application then in a legal sense §39.3 applies to the products installed. Lacking any documentation in the aircraft records that show replacement of the original engine or propeller with something other than a type certificated product, the information on the application then stands.

Part 39 does not stipulate that the compliance with AD's is compulsory only on products that are installed in type-certificated aircraft. Section 39.5 says that the FAA issues airworthiness directive when they find that an unsafe condition exists in a product and the condition is likely to exist or develop in other products of the same type. In addition section 91.7 states that no person may operate an aircraft unless it is in an airworthy condition and that the pilot in command is responsible to determine that the aircraft is a condition for a safe flight. In this regulation the language states "civil aircraft" as opposed to type certificated aircraft. In so wording the rule this way the application of Part 39 to "products" installed in amateur-built aircraft is logical.

Another regulation, section 91.319, gives the FAA inspector or designee who issues an airworthiness certificate to an experimental airplane the authority to issue operating limitations considered necessary for safe operation. These limitations are an addendum to the Airworthy Certificate and each condition must be complied with. I have seen operating limitations for amateur-built airplanes carry the limitation to comply with applicable airworthiness directives for the engine or propeller installed on amateur-built aircraft. The inspector or designee who added this limitation to an amateur-built aircraft's operating limitations has not only helped in assuring a safe aircraft but also helped the owner to stay compliant with operating regulations.

The guidance that this article is predicated on comes mainly from a document produced by the office of legal counsel in the Aircraft Certification Service Engine and Propeller Directorate. The acting Regional Counsel sent a Memorandum in March 2003 that stated the reasoning for AD compliance on amateur-built aircraft. In addition to those stated reasons above he also wrote that AD's that apply to type-certified engines and propellers will continue to apply to those products even if the engine or propeller is installed in an aircraft operating under an experimental airworthiness certificate. The Memorandum also says that the FAA issues AD's based on the type design of the product and that the type design of those products is not altered or affected by the aircraft in which they are installed in. The engine and propeller type design remains separate from the aircraft type design. Under Part 39 the FAA treats each product independently. The AD will continue to apply to the product even if it is used in an aircraft in which the FAA has not approved their installation.

The acting legal counsel also addressed the act of removing data plates to avoid compliance with AD's. His Memorandum states that the act of removing the data plate of a type-certificated product is addressed in Part 45. Section 45.13 of that Part prohibits removing data plates without the approval of the FAA. There are no exceptions granted in that Part for engines or propellers installed in amateur-built aircraft. Simply removing a data plate does not alter the type design or nature of the engine or propeller.

The Memorandum also addressed who can comply with an airworthiness directive. In the memo he confirms that maintenance rules specifically state that amateur-built aircraft are exempt from Part 43. This includes any and all installed items. This means that the person performing the work required to comply with the AD does not have to be certified by the FAA. If the owner believes that he/she is capable and competent or knows of another person who is capable and competent to do the work, then there is no restriction or prohibition on who can get it done.

As with type-certified aircraft, experimental aircraft are required to be inspected for continued safe operation yearly. The inspection is performed by the original builder of the aircraft if the builder holds an repairman certificate for inspecting that aircraft, by a person holding an FAA mechanic certificate, or by an appropriately rated repair station. When the person performing the inspection signs off the aircraft as being in safe condition for operation that certification is also supposed to confirm that all airworthiness directives on installed type-certificated engines or propellers have been complied with. Stating otherwise can place the certificate holder in a situation with the FAA that he/she really wouldn't want to be in.

The FAA's position has been consistent regarding AD compliance on type-certificated engines and propellers installed on experimental aircraft for at least the past 25+ years. The former Field Programs Division of the FAA issued a second FAA Memorandum, which predates the previously mentioned memo. This division is now included in the Aircraft Maintenance Division of the FAA in Washington, D.C. The message in this Memorandum is that AD's are applicable to the product regardless of its application on an aircraft. This Memorandum was written in 1991.

Earlier documents in the form of Advisory Circulars dating back to the mid 1970's have addressed AD compliance in experimental aircraft. Two that I have knowledge of are AC 21-12 and AC 39-7. I have stated in an earlier newsletter that the Federal Aviation Regulations don't change as often as many people think. What changes more frequently is FAA guidance and policy, but in this instance nothing has changed. In other words it's the "ůSame as it ever was".

Upcoming Events
(Clicking on the date will take you to the FAA's website for a descripton of the event.)

January 22
Linn State Technical College
Linn, MO 9 A.M. to 12 P.M.
McDonnell-Douglas Green Aviation Building
Sport Pilot/Light Sport Aircraft

February 5 & 6
30th Super Safety Seminar
Flight Instructor Renewal Clinic
8AM to 5PM.
Anheuser-Busch Auditorium
Lower level Cook Hall
St. Louis University.

February 11& 12
Aviation Maintenance Seminar
Holiday Inn
Collinsville, IL

February 24
The Successful Cross Country
The Landing Place Restaurant
Cape Girardeau Airport
Cape Girardeau, MO
7:00 PM

Register at http//faasafety.gov for E-mail notification of safety seminars in the St. Louis District.

Good Maintenance is No Accident
Steven Long

Airworthiness Safety Program Manager
800-322-8876 ext 4830