Summary
We propose to adopt a new airworthiness directive (AD) for certain Rolls-Royce Deutschland Ltd & Co KG (RRD) Spey 511-8 turbojet engines. This proposed AD was prompted by a recent quality review determination that bolts with reduced material properties may have been installed in some engines. This proposed AD would require inspection and replacement if necessary, of affected bolts, and if any bolt is found broken, inspection of the adjacent disc(s) for damage. We are proposing this AD to prevent uncontained turbine disc fracture and damage to the airplane.