EASA SIB CASA-2021-09
In-flight Shutdown Events due to Failure of Smiths Electronic Engine Control Units
Summary
The Transport Canada Civil Aviation Safety Alert CASA 2021-09 addresses an increased rate of in-flight shutdown events on Pratt & Whitney Canada PW305A engines installed on Learjet 60 aircraft, caused by failures of Smiths Electronic Engine Control (EEC) units. The alert highlights the aging-related failures of EEC units with part number 31B4741 and recommends upgrading to the latest EEC configuration. This safety alert is intended for owners, operators, and maintainers of the affected engines.
What Changed
CASA 2021-09 introduces awareness of the increased failure rate of Smiths-manufactured EEC units on PW305A engines and informs that Pratt & Whitney Canada will soon cease repair support for these older units. It recommends compliance with P&WC Service Information Letter PW300-201 and Service Bulletin PW300-72-24434 to upgrade to the latest EEC configuration to mitigate the risk of in-flight shutdowns.
Why It Matters
This alert is critical for aviation professionals as it addresses a safety risk that can lead to engine shutdowns during flight, impacting aircraft reliability and safety. Operators and maintenance organizations must be aware of the aging EEC components and the impending end of repair support to ensure continued airworthiness and compliance. Timely upgrades reduce the risk of engine failures and potential operational disruptions.
What To Do
Affected owners, operators, and maintainers should review and follow the recommendations in P&WC's Service Information Letter PW300-201 and implement the upgrade outlined in Service Bulletin PW300-72-24434. They should plan for the replacement of aging Smiths EEC units promptly to maintain engine reliability. For further information, stakeholders can contact Transport Canada or the designated continuing airworthiness office.