Is AD 01-11968 a recurring Airworthiness Directive?

No — AD 01-11968 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 01-11968 apply to?

AD 01-11968 applies to Air Tractor, Inc. At-400, At-500, And At-800 — models AT-400, AT-500, AT-800. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 01-11968

one-time

AD 01-11968 · 2001-05-16 · airframe

Airworthiness Directives; Air Tractor, Inc. AT-400, AT-500, and AT-800 Series Airplanes

What this AD requires

This amendment supersedes Airworthiness Directive (AD) 2000- 14-51, which requires inspection of the wing lower spar cap for cracks on Air Tractor, Inc. (Air Tractor) Models AT-501, AT-502, and AT-502A airplanes, and modification or replacement of any cracked wing lower spar cap. This AD lowers the safe life for the wing lower spar cap on Air Tractor AT-400, AT-500, and AT-800 series airplanes. This AD is the result of numerous reports of cracks in the \3/8\-inch bolthole of the wing lower spar cap on the affected airplanes. The actions specified by this AD are intended to prevent fatigue cracks from occurring in the wing lower spar cap before the originally established safe life is reached. Fatigue cracks in the wing lower spar cap, if not detected and corrected, could result in the wing separating from the airplane during flight.

Which aircraft AD 01-11968 applies to

MakesAir Tractor, Inc. At-400, At-500, And At-800

ModelsAT-400, AT-500, AT-800

applicability derived from the AD summary — confirm the model/serial from the records

Whether AD 01-11968 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 01-11968 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.