Airworthiness Directive · Amendment 39-14150 · Sikorsky Aircraft Corporation Model S-92A Helicopters
Sikorsky Aircraft Corporation Model S-92A Helicopters
Model S-92A helicopters, with a gear box output housing, part number (P/N) 92358-06109-043, installed, certificated in any category.
This amendment adopts a new airworthiness directive (AD) for the Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This action requires replacing a certain part-numbered tail gear box output housing that has 600 or more hours time-in-service (TIS) with an airworthy part. Also, this AD revises the Airworthiness Limitations section of the maintenance manual by reducing the life limit of the tail gear box output housing. This amendment is prompted by the premature failure of the tail gear box output housing during fatigue testing by the manufacturer. The actions specified in this AD are intended to prevent fatigue failure of the tail gear box output housing, loss of tail rotor drive, and subsequent loss of control of the helicopter.
To prevent fatigue failure of the tail gear box output housing, loss of tail rotor drive, and subsequent loss of control of the helicopter, do the following:
(a) Before further flight, replace each tail gear box output housing, P/N 92358-06109-043, with 600 or more hours time-in-service (TIS) with an airworthy tail gear box housing with less than 600 hours TIS.
Note: Sikorsky Maintenance Manual SA S92A-AWL-000, Airworthiness Limitations and Inspection Requirements, Chapter 4, dated March 3, 2005, contains the limitation for the tail gear box output housing.
(b) This AD revises the Airworthiness Limitations section of the maintenance manual by reducing the life limit of the tail gear box output housing from 4500 hours TIS to 600 hours TIS.
(c) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Contact the Boston Aircraft Certification Office, FAA, for information about previously approved alternative methods of compliance.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
