Is AD 2011-21-12 a recurring Airworthiness Directive?

No — AD 2011-21-12 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2011-21-12 apply to?

AD 2011-21-12 applies to Sikorsky — models S-64F, S-64. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2011-21-12

one-time

Official AD 2011-21-12 · FR doc 2011-27775 · 2011-10-27 · airframe

Airworthiness Directives; Erickson Air-Crane Incorporated Model S-64F Helicopters

What this AD requires

We are adopting a new airworthiness directive (AD) for the Erickson Air-Crane (Erickson Air-Crane) Model S-64F helicopters. The amendment requires, at specified intervals, certain inspections of the rotating swashplate assembly (swashplate) for a crack. If a crack is found, this AD also requires, before further flight, replacing the swashplate with an airworthy swashplate. This AD is prompted by a report from the manufacturer of a swashplate cracking during fatigue testing. We are issuing this AD to prevent loss of a swashplate due to a fatigue crack, loss of control of the main rotor system, and subsequent loss of control of the helicopter.

Which aircraft AD 2011-21-12 applies to

MakesSikorsky

ModelsS-64F, S-64

Part-conditional — 65104-11001-051.

Applies only to helicopters with rotating swashplate assembly P/N 65104-11001-051 installed.

Whether AD 2011-21-12 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 2011-21-12 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.