Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: It has been evidenced by test that the tightening torque settings on the Rolls Royce Trent 500 and Trent 700 forward (FWD) and aft (AFT) engine mount link pin retention bolts have always been higher than the design value. These bolts retain the washers that maintain the engine mount vertical load pins in position. If bolts, as a consequence of the over-torque, fail and move away, it would lead to loss of the vertical load pins, which could result in loss of the primary and/or secondary load path of the forward and/or aft engine mount which could potentially lead to engine separation. The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.