Is AD 2021-18-15 a recurring Airworthiness Directive?

No — AD 2021-18-15 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2021-18-15 apply to?

AD 2021-18-15 applies to Pzl Swidnik S.A. — models W-3A, W-3. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2021-18-15

one-time

Official AD 2021-18-15 · FR doc 2021-20830 · 2021-09-27 · airframe

Airworthiness Directives; PZL Swidnik S.A. Helicopters

What this AD requires

The FAA is adopting a new airworthiness directive (AD) for certain PZL Swidnik S.A. Model PZL W-3A helicopters. This AD was prompted by a report that displaced teeth were detected on the moveable assemblies of a main rotor (MR) blade droop stop. This AD requires removing from service the moveable assemblies from each affected MR blade droop stop and prohibits installation of an affected MR blade droop stop and moveable assemblies of affected MR blade droop stops. The FAA is issuing this AD to address the unsafe condition on these products.

Which aircraft AD 2021-18-15 applies to

MakesPzl Swidnik S.A.

ModelsW-3A, W-3

Part-conditional — 37.21.800.00.00.

Applies only to helicopters with movable assemblies of main rotor (MR) blade droop stop, part number 37.21.800.00.00, installed.

Whether AD 2021-18-15 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 2021-18-15 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.