Airworthiness Directive · Amendment 39-21926 · Global positioning system
Sikorsky Aircraft Corporation Helicopters
This AD applies to Sikorsky Aircraft Corporation Model S-76D helicopters, certificated in any category, with Thales Global Positioning System (GPS) TopStar 200 LPV receiver part number (P/N) C17149HA01 installed.
The FAA is adopting a new airworthiness directive (AD) for certain Sikorsky Aircraft Corporation Model S-76D helicopters. This AD was prompted by reports that certain Thales global positioning system (GPS) satellite based augmentation system (SBAS) receivers provided, under certain conditions, erroneous outputs on aircraft positions. This AD requires replacing affected GPS receivers and prohibits installing those GPS receivers. The FAA is issuing this AD to address the unsafe condition on these products.
(1) Within 130 hours time-in-service after the effective date of this AD, replace each affected GPS receiver identified in paragraph (c) of this AD with GPS receiver P/N C17149RA01 in accordance with the Accomplishment Instructions, paragraphs A., C., and D., of Sikorsky S-76D Helicopter Service Bulletin SB 76-017, Basic Issue, dated May 11, 2021.
(2) As of the effective date of this AD, do not install a GPS receiver identified in paragraph (c) of this AD on any helicopter.
(3) Accomplishing paragraph (g)(1) of this AD terminates the requirements of AD 2020-08-02.
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
