Is AD 2009-23-51 a recurring Airworthiness Directive?

No — AD 2009-23-51 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2009-23-51 apply to?

AD 2009-23-51 applies to Sikorsky — models S-92A, S-92. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2009-23-51

one-time

Official AD 2009-23-51 · FR doc 2010-1723 · 2010-02-04 · airframe

Airworthiness Directives; Sikorsky Aircraft Corporation Model S-92A Helicopters

What this AD requires

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2009-23-51, which was sent previously to all known U.S. owners and operators of Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters by individual letters. This AD requires cleaning and inspecting each main gearbox (MGB) assembly mounting foot pad and rib for a crack and corrosion. If you do not find a crack, the AD requires applying a corrosion preventive compound. If you find a crack, the AD requires replacing the MGB before further flight. If you find corrosion, bubbled paint, or paint discoloration, the AD also requires you to repair the MGB before further flight. This amendment is prompted by reports of cracks in the MGB mounting foot pads and foot ribs. This condition, if not detected, could result in loss of the MGB and subsequent loss of control of the helicopter.

Which aircraft AD 2009-23-51 applies to

MakesSikorsky

ModelsS-92A, S-92

Part-conditional — 92351-15000-042, 92351-15000-043, 92351-15110-042, 92351-15110-043, 92351-15110-044, 92351-15110-045.

Applies only when main gearbox (MGB) assembly P/N 92351-15000-042 or -043, with MGB housing P/N 92351-15110-042, -043, -044, or -045, is installed.

Whether AD 2009-23-51 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 2009-23-51 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.