Airworthiness Directives; General Electric Company Engines, and Various Restricted Category Rotorcraft

The FAA is adopting a new airworthiness directive (AD) for certain General Electric Company (GE) Model CT7-2E1, CT7-2F1, CT7-8A, CT7-8E, CT7-8F5 engines, and various restricted category helicopters with GE Model T700-GE-700,-701A, -701C, -701D/CC, -701D, -401, -401C, CT7-2D or CT7-2D1 engines installed. This AD was prompted by at least four reports of failures of the torque reference tube magnetic insert braze joint of the power turbine drive shaft assembly within the last several months. This AD requires a phase array ultrasonic inspection of the torque reference tube magnetic insert braze joint of the power turbine drive shaft assembly for inadequate braze coverage, and repair or replacement of the power turbine drive shaft assembly if necessary. The FAA previously sent an emergency AD to all known U.S. owners and operators of these engines and helicopters and is now issuing this AD to address the unsafe condition on these products.