EASA SIB 2015-03R1
ATR 42-400, 42-500 and 72-212A aeroplanes - Propeller / Engine Vibrations In Flight
Summary
EASA Safety Information Bulletin 2015-03R1 is an airworthiness communication addressing propeller and engine vibrations in flight affecting ATR 42-400, 42-500, and 72-212A aeroplanes equipped with Hamilton Sundstrand model 568F-1 propellers. The bulletin informs operators about reported damages to propeller pitch change mechanisms linked to severe vibrations during descent near maximum operating speed with power levers at flight idle. It provides guidance to improve crew awareness and recommends preventive measures to mitigate the risk of such vibrations.
What Changed
This revision of EASA SIB 2015-03 updates the reference publications and clarifies recommended actions after experiencing propeller or engine vibrations. It emphasizes crew procedures for identifying and managing the vibration event, including engine shutdown protocols and avoidance of reverse thrust if engine discrimination is difficult. The update also stresses the importance of reporting any sudden unusual vibrations during descent or approach.
Why It Matters
This bulletin is important for aviation professionals because it highlights a potential airworthiness concern that can lead to propeller mechanism damage and in-flight vibrations, which could affect flight safety and aircraft operability. Operators and maintenance teams need to be aware of the symptoms and recommended procedures to promptly address the issue, minimizing risk and ensuring continued safe operation of affected ATR aircraft. It also guides compliance with manufacturer recommendations and reporting protocols.
What To Do
Operators should adhere to ATR's recommended descent speed limits, perform smooth power lever reductions, and follow prescribed procedures to shut down affected engines if vibrations occur. Crews must avoid using reverse thrust if engine shutdown is unclear and report any unusual vibrations to maintenance organizations. Operators should review the referenced ATR and UTC Aerospace Systems publications for troubleshooting guidance and report incidents to ATR. No mandatory compliance deadline is specified as the bulletin provides non-mandatory recommendations.