EASA AD US-2022-10-06
Engine - Stage 3-4 Turbine Wheels - Replacement
Summary
The FAA Airworthiness Directive 2022-10-06 is a final rule addressing Rolls-Royce Corporation 250 series turboshaft engines, including models 250-C20, 250-C20B, 250-C20C (T63-A-720), 250-C20F, 250-C20J, 250-C20R variants, 250-C20W, 250-C300/A1, and 250-C300/B1. It mandates replacement of the 3rd-stage turbine wheel (P/N 23065818) and 4th-stage turbine wheels (P/N 23055944 or RR30000240) due to in-service turbine blade failures that caused power loss and engine shutdowns. This directive supersedes AD 2017-18-14 and updates the applicability to include an additional engine model.
What Changed
This AD supersedes the previous AD 2017-18-14 by requiring mandatory replacement of both the 3rd-stage and 4th-stage turbine wheels with redesigned parts featuring increased blade fillets. It expands applicability to include the 250-C20C (T63-A-720) engine model. The directive also updates the referenced Rolls-Royce service information to the latest revision.
Why It Matters
This directive is critical for aviation professionals to prevent turbine blade failures that can lead to engine power loss and in-flight shutdowns, enhancing flight safety. Operators and maintenance organizations must ensure compliance to avoid unsafe conditions and potential operational disruptions. The updated requirements and parts ensure improved engine reliability and reduce the risk of unplanned maintenance.
What To Do
Affected operators must replace the 3rd-stage turbine wheel P/N 23065818 with the redesigned P/N M250-10473 and replace the 4th-stage turbine wheels P/N 23055944 or RR30000240 with their respective redesigned parts. Compliance with this AD is mandatory by June 28, 2022. Operators should consult Rolls-Royce Alert Commercial Engine Bulletins Revision 2 dated December 8, 2021, for detailed replacement procedures.
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