Action
Final rule; request for comments.
Summary
We are adopting a new airworthiness directive (AD) for all Rolls-Royce Deutschland Ltd & Co KG BR700-715A1-30, BR700-715B1-30, and BR700-715C1-30 turbofan engines. This AD requires a one-time removal from service of the high-pressure (HP) compressor stages 1 to 6 rotor disc assembly before exceeding certain thresholds. This AD was prompted by a report of silver chloride-induced stress corrosion cracking of the HP compressor stages 1 to 6 rotor disc assembly, identified during overhaul. We are issuing this AD to prevent failure of the HP compressor stages 1 to 6 rotor disc assembly, which could result in uncontained failure of the engine and damage to the airplane.