Airworthiness Directive · Amendment 39-17895 · Rolls-Royce plc Turbofan Engines
Rolls-Royce plc Turbofan Engines
This AD applies to all Rolls-Royce plc (RR) RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines prior to engine serial number 42066.
We are adopting a new airworthiness directive (AD) for certain Rolls-Royce plc (RR) RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines. This AD requires modification of the engine by removing an electronic engine control (EEC) incorporating EEC software standard A14 or earlier and installing an EEC eligible for installation. This AD was prompted by an uncontained multiple turbine blade failure on an RR RB211 Trent 772B turbofan engine. We are issuing this AD to prevent failure of the intermediate-pressure (IP) turbine disk drive arm or burst of the high-pressure turbine disk, which could lead to uncontained engine failure and damage to the airplane.
After the effective date of this AD, at the next engine shop visit or by December 31, 2018, whichever occurs first, modify the engine by removing any electronic engine control (EEC) that incorporates EEC software standard A14 or earlier and installing an EEC eligible for installation.
After modification of an engine as required by paragraph (e) of this AD, do not install an EEC with software standard A14 or earlier into that engine.
(1) For the purpose of this AD, an “engine shop visit” is the induction of an engine into the shop for maintenance involving the separation of pairs of major mating engine flanges, except that the separation of engine flanges solely for the purposes of transportation without subsequent engine maintenance does not constitute an engine shop visit.
(2) For the purpose of this AD, an EEC “eligible for installation” is any EEC that does not contain software standard A14 or earlier.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
