Summary
We propose to adopt a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, S-76B, S-76C, and S-76D helicopters. This proposed AD would require inspecting the main rotor (M/R) servo pushrod (pushrod) assembly and applying slippage marks. This proposed AD is prompted by an accident of a Sikorsky Model S-76C helicopter caused by a failed pushrod assembly. The proposed actions are intended to prevent an unsafe condition on these products.