Airworthiness Directive · Amendment 39-11205 · Sikorsky Aircraft Model S-76A Helicopters
Sikorsky Aircraft Model S-76A Helicopters
Sikorsky Model S-76A helicopters with Turbomeca Arriel 1S1 engines installed in accordance with Supplemental Type Certificate SH568NE, including drawing number 76070-30601.
This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 99-11-04 which was sent previously to all known U.S. owners and operators of Sikorsky Aircraft Model S-76A helicopters by individual letters. This AD requires, before further flight, either revising the flight manual to show reduced single-engine rotorcraft performance or determining if an AC generator interlock system is installed. If an interlock system is installed, the flight manual revision is not required. This amendment is prompted by the discovery that Sikorsky Aircraft Model S-76A helicopters with Turbomeca Arriel 1S1 engines may fail to achieve the specified single- engine rotorcraft performance if an AC generator interlock system is not installed. The actions specified by this AD are intended to prevent the inability of the rotorcraft to achieve certain published one- engine-inoperative performance.
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
