Federal Aviation Administration September 3, 2013 – Federal Register Recent Federal Regulation Documents

We are superseding airworthiness directive (AD) 2012-10-12 for all RR RB211-Trent 553-61, 553A2-61, 556-61, 556A2-61, 556B-61, 556B2- 61, 560-61, 560A2-61, 768-60, 772-60, 772B-60, 875-17, 877-17, 884-17, 884B-17, 892-17, 892B-17, and 895-17 turbofan engines. AD 2012-10-12 required inspecting the intermediate-pressure (IP) compressor rotor shaft rear balance land for cracks. We are issuing this AD to require inspections of the IP compressor rotor shaft, as required by AD 2012- 10-12, to add on-wing inspections for the Trent 500 engines, and to add on-wing and in-shop inspections for the Trent 900 engines. This AD was prompted by detection of a crack in a Trent 500 IP compressor rotor shaft rear balance land during a shop visit. Further engineering evaluation, done by RR, concluded that the cracking may also exist in Trent 900 engines. We are issuing this AD to detect cracking on the IP compressor rotor shaft rear balance land, which could lead to uncontained engine failure and damage to the airplane.