AD NUMBER: 2019-05-02

PRODUCT: Certain Rolls-Royce plc (RR) RB211-Trent 900 turbofan engine models.

ACTION: Final rule; request for comments.

SUMMARY: The FAA is superseding airworthiness directive (AD) 2017-22-13 for the product listed above.

AD 2017-22-13 required an inspection of the drains mast and the replacement or repair of the drains mast if a crack is found.

This AD retains this requirement, but adds repetitive inspections and expands the population of affected RR RB211-Trent 900 turbofan engine models.

This AD was prompted by RR in-service findings that indicated a need to include part number (P/N) FW29847 drains mast and additional RR RB211-Trent 900 turbofan engines to the affected population.

DATES: This AD is effective March 27, 2019. Comments must be received by April 26, 2019.

COST: The FAA estimates that this AD affects zero engines installed on airplanes of U.S. registry. Operators may incur the following costs in order to comply with this AD:

• Inspect the drains mast 2 work-hours × $85 per hour = $170 per engine.

On-Condition costs:

• Replace the drains mast 1 work-hour × $85 per hour = $85. Parts: $72,000, Cost per engine: $72,085.
• Seal the drains mast 1 work-hour × $85 per hour = $85 per engine.

FMI: AD