Who can sign an E-AB condition inspection? Light-sport repairmen, builders and mechanics

Who can sign the annual condition inspection on an experimental amateur-built (E-AB) airplane? Since the MOSAIC rule, a light-sport repairman can be one answer, but only when the repairman's certificate and the operating limitations issued to that particular airplane both allow it. Owners often miss the second.

Four questions that sound like one

Aircraft certification is the airworthiness certificate an airplane holds; an E-AB holds an experimental certificate under section 21.191(g). Operating limitations are conditions issued with it. Inspection authority is who may perform the required condition inspection, under the applicable certificate privileges and the aircraft's issued operating limitations. Ordinary maintenance on an E-AB aircraft is a separate question; do not assume it requires the same certificate. Pilot privileges are separate again: FAA guidance says repairman privileges do not extend to standard-category aircraft, even ones a sport pilot can fly.

Two repairman certificates, not one

The FAA issues three types of repairman certificates under Part 65, each with its own eligibility, privileges and limitations. Two matter here.

A builder repairman certificate (section 65.104) goes to the primary builder of an aircraft and lets the holder perform condition inspections on the aircraft the holder constructed, in accordance with that aircraft's operating limitations.

A repairman certificate (light-sport) (sections 65.107 and 65.109) comes from FAA-accepted training. It can carry an inspection rating (a 16-hour course on inspecting the category and class of experimental aircraft), a maintenance rating (a course built on the Aviation Mechanic General, Airframe and Powerplant standards), or both. It is issued with category privileges and may carry class limits. A repairman certificate (light-sport aircraft) that was issued before and was valid on October 22, 2025 is equivalent to a repairman certificate (light-sport) with the same ratings.

The FAA says these are different certificates; a primary builder wanting the light-sport one must meet its own eligibility requirements.

What a condition inspection is

The FAA's MOSAIC preamble notes that E-AB aircraft are not required to be maintained under Part 43. Instead the FAA issues operating limitations under section 91.319(i), which are part of the airworthiness certificate. One issued to the majority of E-AB aircraft prohibits operation unless, within the preceding 12 calendar months, the aircraft has had a condition inspection per the scope and detail of Part 43 Appendix D. Section 91.409(c) exempts aircraft with a current experimental certificate from the annual and 100-hour inspections of 91.409(a) and (b).

Part 43 is not excluded for every experimental aircraft. Section 43.1(b) excludes an experimental-certificate aircraft unless the FAA previously issued it a different kind of airworthiness certificate, with further exceptions for former light-sport aircraft and Part 107 operations.

Who may do it, when the limitations allow

The FAA's FAQ says this depends on the repairman's ratings and category and class privileges, and on the operating limitations issued to the airplane.

• Inspection rating: only an aircraft the holder owns, with an experimental certificate under 21.191(g), (i), (k) or (l), in the category and class of the training. FAA guidance adds that the holder must be identified as an owner in the FAA registration records.
• Maintenance rating: may perform it on those experimental aircraft and need not own the aircraft (AC 65-32B). FAA guidance applies the category-and-class limit here too; that is guidance, not rule text, since section 65.109(b)(2) does not repeat it.
• Mechanic: the FAA's FAQ says a certificated mechanic may perform inspections and maintenance on light-sport and experimental aircraft, within Part 65 limits.

The preamble says the E-AB expansion covers section 21.191(g) aircraft, not other experimental purposes.

When an inspection program replaces it

Depending on complexity, the FAA may prescribe limitations requiring an inspection program meeting section 91.409(f). The preamble says those inspections are not condition inspections and must be performed by a certificated mechanic or repair station. Section 91.409(e) lists the kinds of aircraft that must follow such a program: large airplanes (to which Part 125 is not applicable), turbojet multiengine airplanes, turbopropeller-powered multiengine airplanes and turbine-powered rotorcraft. It also permits a turbine-powered rotorcraft owner or operator to elect the inspection provisions of (a), (b), (c) or (d) instead of an (f) program. That is a general regulatory option, separate from what an individual experimental aircraft’s issued limitations require, so your limitations say which applies.

The issued limitations decide

FAA Orders contain sample wording for these limitations, and it changed. Order 8130.2K's (effective December 2, 2024) named the builder repairman or "an appropriately rated FAA-certificated mechanic." Order 8130.2L's (effective January 30, 2026) adds "a light-sport repairman certificated under § 65.107 (in accordance with their certificate privileges under § 65.109)." Treat both as historical sample wording, not what any airplane was issued: Appendix D recognizes limitations issued with modifications or omissions, and AC 65-32B (guidance, not a binding rule) says to refer to the limitations issued to the specific aircraft.

The FAA's maintenance FAQ says E-AB certificates issued before Revision L typically lack language letting a light-sport repairman do the inspection. The owner or authorized agent may request an amendment through a Flight Standards District Office or the ASKME airworthiness certification portal; the FAA will typically re-issue all the operating limitations.

What the privileges do not cover

Standard-category aircraft are outside them. An inspection rating does not cover light-sport category (21.190) aircraft. A maintenance rating can approve those for return to service, but excludes major repairs or alterations on FAA-approved products, and a major repair first needs additional training. Part 43 applies to light-sport category aircraft, with the three exceptions in section 43.1(d) for products not produced under an FAA approval.

A hypothetical example

Imagine you own an amateur-built airplane and a friend holds a light-sport repairman certificate. Can the friend do your condition inspection? It depends on the limitations issued to your airplane, so read the one on your certificate. If it names light-sport repairmen, the friend's rating, category and class, and (for an inspection rating) ownership must also fit. If it does not, you could request an amendment. Those are the checks, in that order; whether any real aircraft or person qualifies depends on the documents.

The takeaway

Before arranging the inspection, confirm the repairman's rating, category and class and, for an inspection rating, ownership; read the limitations printed for your airplane; and request an amendment if they do not fit.