Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all Rolls-Royce Deutschland Ltd & Co KG (RRD) Model Trent 1000-AE3, Trent 1000-CE3, Trent 1000-D3, Trent 1000-G3, Trent 1000-H3, Trent 1000-J3, Trent 1000-K3, Trent 1000-L3, Trent 1000-M3, Trent 1000-N3, Trent 1000-P3, Trent 1000-Q3, and Trent 1000-R3 engines. This proposed AD was prompted by reports of wear in the combining spill-valve (CSV) assembly of certain hydro-mechanical units (HMUs). This proposed AD would require removing certain HMUs from service and replacing with a serviceable part or modifying the HMU by replacing the CSV assembly, which is an optional terminating action; and would prohibit installing certain HMUs unless the HMU is a serviceable part, as specified in a European Union Aviation Safety Agency (EASA) AD, which is proposed for incorporation by reference. The FAA is proposing this AD to address the unsafe condition on these products.