Is AD 2021-13-21 a recurring Airworthiness Directive?

Yes — AD 2021-13-21 requires a repetitive inspection every 25 hours. Next-due depends on the aircraft's time in service.

Which aircraft does AD 2021-13-21 apply to?

AD 2021-13-21 applies to Leonardo — models AB139, AW139, AW189. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2021-13-21

recurring

Official AD 2021-13-21 · FR doc 2021-13668 · 2021-06-25 · airframe

Airworthiness Directives; Leonardo S.p.a. Helicopters

What this AD requires

The FAA is adopting a new airworthiness directive (AD) for certain Leonardo S.p.a. Model AB139, AW139, and AW189 helicopters. This AD was prompted by a report of the in-flight failure of one of the three stainless steel external rings bonded to the main rotor swashplate boot. This AD requires repetitive inspections of these stainless steel external rings for corrosion, cracks, and the condition of the adhesive that bonds the rings to the main rotor swashplate boot, and corrective action if necessary, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products.

Repetitive inspection. Re-inspect every 25 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 2021-13-21 applies to

MakesLeonardo

ModelsAB139, AW139, AW189

Part-conditional — 3G6230V00251.

Applies to helicopters equipped with a main rotor swashplate boot, P/N 3G6230V00251.

Whether AD 2021-13-21 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 2021-13-21 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.