Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76C Helicopters

This amendment adopts a new airworthiness directive (AD) for the specified Sikorsky Aircraft Corporation (Sikorsky) Model S-76C helicopters. This action requires inspecting the emergency flotation system squib connector (flotation system connector) to determine if a metallic foil shunt is installed. This amendment is prompted by a discovery that a metallic foil shunt meant to prevent inadvertent activation of a flotation system during installation was still installed in the left-hand flotation system connector of a Model S-76C helicopter. The actions specified in this AD are intended to determine if a metallic foil shunt is installed in the flotation system, which could prevent the flotation system from deploying and could prevent the helicopter from staying afloat long enough to enable emergency evacuation after a water landing.