Action
Supplemental notice of proposed rulemaking (NPRM); reopening of comment period.
Summary
We are revising an earlier proposed airworthiness directive (AD) 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. That NPRM proposed to supersede an existing AD that requires inspecting the intermediate-pressure (IP) compressor rotor shaft rear balance land for cracks, which could lead to engine failure. This action revises that NPRM by changing the optional terminating action for RB211-Trent 700 and RB211-Trent 800 engines to mandatory terminating action. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes.