AD NUMBER: 2012-02-11

PRODUCT: All RR RB211-535E4-37, -535E4-B-37, -535E4-B-75, and -535E4-C-37 turbofan engines.
SUBJECT: Airworthiness Directive 2012-02-11
ACTION: Final rule

SUMMARY: The FAA is superseding an existing airworthiness directive (AD) for all RR RB211-535E4- 37, -535E4-B-37, -535E4-B-75, and -535E4-C-37 turbofan engines.

That AD currently requires performing initial and repetitive visual and fluorescent penetrant inspections (FPI) of the lowpressure (LP) turbine stage 1, 2, and 3 discs to detect cracks in the discs.

This new AD continues to require those inspections and changes the definition of a shop visit to be less restrictive. This AD was prompted by our finding that the definition of shop visit in the existing AD was too restrictive.

The FAA is issuing this AD to revise the definition of shop visit and to detect cracks in the LP turbine stage 1, 2, and 3 discs, which could result in an uncontained release of LP turbine blades and damage to the airplane.

DATES: This AD is effective March 6, 2012.

FMI: AD