Airworthiness Directive 2009-07-53
one-timeAirworthiness 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) 2009-07-53, 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 amendment is prompted by the failure of 2 main gearbox filter bowl assembly studs (studs) that were found broken during a fatal accident investigation in Canada. Prior to the accident, the manufacturer was investigating a July 2008 incident that also involved broken studs. In both cases, the broken studs resulted in rapid loss of oil. The failures have been tied to fretting and galling of the original titanium studs; therefore, this AD requires removing all titanium studs and replacing them with steel studs. The actions specified by this AD are intended to prevent failure of a stud, which could result in rapid loss of oil, failure of the main gearbox, and subsequent loss of control of the helicopter.
Which aircraft AD 2009-07-53 applies to
Applies only to main gearbox housing assemblies with the listed part numbers that are NOT marked with "TS-062-01" near the part number.
Whether AD 2009-07-53 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:
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.