Is AD 97-17533 a recurring Airworthiness Directive?

Yes — AD 97-17533 requires a repetitive inspection. Next-due depends on the aircraft's time in service.

Which aircraft does AD 97-17533 apply to?

AD 97-17533 applies to Air Tractor Incorporated — models AT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, AT-502. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 97-17533

recurring

AD 97-17533 · 1997-07-18 · airframe

Airworthiness Directives; Air Tractor Incorporated Models AT-301, AT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, and AT-502 Airplanes

What this AD requires

This amendment supersedes Airworthiness Directive AD 95-20-06, which applies to certain Air Tractor Incorporated (Air Tractor) Models AT-301, AT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, and AT-502 airplanes and currently requires repetitively inspecting the front spar attachment lugs and the rear spar for fatigue cracks, and modifying the vertical fin if cracks are found. The modification terminates the repetitive inspection requirement of AD 95-20-06 and may be incorporated at any time, if cracks are not found. The FAA has determined that the Air Tractor Models mentioned above with a \1/4\- inch fin front spar fitting installed should be exempt from the AD. The AD will retain the requirements of AD 95-20-06 for all Air Tractor airplanes that have a \3/16\-inch fin front spar fitting. The actions specified by this AD are intended to prevent in-flight vertical fin cracking, which, if not detected and corrected, could result in structural failure of the front spar attachments and eventually the rear spar attachment and cause loss of directional control of the airplane.

Repetitive inspection. Re-inspect. The next-due date/hours depend on this aircraft’s time in service — a records report computes it from the logbooks.

Which aircraft AD 97-17533 applies to

MakesAir Tractor Incorporated

ModelsAT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, AT-502

certain

Whether AD 97-17533 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.

How AD compliance is recorded

A valid compliance record (14 CFR 43.9) states:

Method of compliance — The specific action taken (inspected, replaced, modified) and to what revision.

Date — When the work was done.

Aircraft time — Total time in service / tach at compliance — how recurring next-due is computed.

Signature & certificate — The A&P/IA who returned it to service, with certificate number.

Is AD 97-17533 complied with on your aircraft?

Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.

Look up a tail number →Read the full directive (Federal Register)

Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.