Is AD 2021-05-14 a recurring Airworthiness Directive?

Yes — AD 2021-05-14 requires a repetitive inspection every 900 hours. Next-due depends on the aircraft's time in service.

Which aircraft does AD 2021-05-14 apply to?

AD 2021-05-14 applies to Air Tractor, Inc. — models AT-400A, AT-401A, AT-401B, AT-402A, AT-402B, AT-502A, AT-502B, AT-503A. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2021-05-14

recurring

Official AD 2021-05-14 · FR doc 2021-06142 · 2021-03-25 · airframe

Airworthiness Directives; Air Tractor, Inc., Airplanes

What this AD requires

The FAA is adopting a new airworthiness directive (AD) for all Air Tractor, Inc., (Air Tractor) Models AT-250, AT-300, AT-301, AT-302, AT-400, AT-400A, AT-401, AT-401A, AT-401B, AT-402, AT-402A, AT-402B, AT-501, AT-502, AT-502A, AT-502B, AT-503, AT-503A, AT-504, AT-602, AT- 802, and AT-802A airplanes. This AD was prompted by reports of cracks in the flap torque tube actuator attachment brackets that may cause the flap actuator to detach from the flap torque tube. This AD requires repetitive visual and dye penetrant inspections of the flap actuator attachment bracket welds for cracks and replacement if cracks are identified. The FAA is issuing this AD to address the unsafe condition on these products.

Repetitive inspection. Re-inspect every 900 hours. The next-due date/hours depend on this aircraft’s time in service — a records report computes it from the logbooks.

Which aircraft AD 2021-05-14 applies to

MakesAir Tractor, Inc.

ModelsAT-400A, AT-401A, AT-401B, AT-402A, AT-402B, AT-502A, AT-502B, AT-503A, AT-802A, AT-250, AT-300, AT-301, AT-302, AT-400, AT-401, AT-402, AT-501, AT-502, AT-503, AT-504, AT-602, AT-802

Applies to all serial numbers of the listed models.

Whether AD 2021-05-14 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 2021-05-14 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.