Airworthiness Directive · Amendment 39-14119 · Sikorsky Aircraft Corporation Model S-92A Helicopters
Sikorsky Aircraft Corporation Model S-92A Helicopters
Model S-92A helicopters with main gearbox (MGB) lubrication/scavenge pump, part number (P/N) 92351-15800-101, with vespel spline adapter, P/N 1584000-1, installed, certificated in any category.
This amendment adopts a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-92A helicopters. This action requires replacing the main gearbox (MGB) lubrication/scavenge pump vespel spline adapters (vespel spline adapters) before further flight, and thereafter, replacing them at certain intervals. This amendment is prompted by a reported incident of an in-flight loss of oil pressure. The actions specified in this AD are intended to prevent loss of lubrication to the MGB, which could cause failure of one or both engine input drives, or planetary gear to sun gear tooth mesh failure, resulting in loss of power to the rotor system and subsequent loss of control of the helicopter.
To prevent loss of lubrication to the MGB, which could cause failure of one or both engine input drives, or planetary gear to sun gear tooth mesh failure, resulting in loss of power to the rotor system and subsequent loss of control of the helicopter, accomplish the following:
(a) Remove and replace each MGB lubrication/scavenge pump vespel spline adapter in accordance with paragraph 3.A., steps (1) through (6) of the Accomplishment Instructions in Sikorsky Aircraft Corporation Alert Service Bulletin No. 92-63-001, dated April 1, 2005.
(b) 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, Engine and Propeller Directorate, FAA, for information about previously approved alternative methods of compliance.
(c) The removals and replacements shall be done in accordance with paragraph 3.A., steps (1) through (6) of the Accomplishment Instructions in Sikorsky Aircraft Alert Service Bulletin No. 92-63-001, dated April 1, 2005. The Director of the Federal Register approved this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Sikorsky Aircraft Corporation, Attn: Manager, Commercial Tech Support, 6900 Main Street, Stratford, Connecticut 06614, phone (203) 386-3001, fax (203) 386-5983. Copies may be inspected at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
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
