Is AD 2021-14-18 a recurring Airworthiness Directive?

Yes — AD 2021-14-18 requires a repetitive inspection every 25 hours. Next-due depends on the aircraft's time in service.

Which aircraft does AD 2021-14-18 apply to?

AD 2021-14-18 applies to Leonardo S.P.A. — models AB139, AW139. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2021-14-18

recurring

Official AD 2021-14-18 · FR doc 2021-15303 · 2021-07-20 · airframe

Airworthiness Directives; Leonardo S.p.a. (Type Certificate Previously Held by Agusta S.p.A.) Helicopters

What this AD requires

The FAA is superseding Airworthiness Directive (AD) 2011-18-52 for certain Agusta S.p.A. (now Leonardo S.p.a.) Model AB139 and AW139 helicopters. AD 2011-18-52 required revising the life limit for certain part-numbered tail rotor (T/R) blades, updating the helicopter's historical records, repetitively inspecting each T/R blade for a crack or damage, and depending on the results, replacing the T/R blade. This AD was prompted by the manufacturer developing improved T/R blades using different materials and establishing life limits for each improved blade. This AD retains certain requirements from AD 2011-18- 52, revises certain requirements from AD 2011-18-52, and expands the applicability to include the newly-designed T/R blades. 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 2021-14-18 applies to

MakesLeonardo S.P.A.

ModelsAB139, AW139

Part-conditional — 3G6410A00131, 3G6410A00132, 3G6410A00133, 4G6410A00131, 4G6410A00132, 4G6410A00133.

Type certificate previously held by Agusta S.p.A. Applies only to helicopters with the listed tail rotor (T/R) blade part numbers installed.

Whether AD 2021-14-18 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 2021-14-18 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.