Bell 206A/B series engine compressor damage - Service Difficulty Advisory

AV 2002-05
21 November 2002

A recent SDR describes an in-flight occurrence caused when the engine compressor ingested a nut plate, which had come loose from the engine bellmouth assembly. This resulted in a violent yaw and partial loss of power. The pilot entered into an autorotation and successfully landed with minimal damage to the aircraft.

The above incident could have been avoided had the manufacturer's recommendation to replace the nut plate as per Technical Bulletin 206-81-56 been incorporated.

Aircraft manufacturers issue numerous recommendations in the form of technical bulletins, service bulletins, service information letters, etc. with the objective of improving reliability and safety. Although such publications are not mandatory, it is recommended that these instructions should be followed.

In this particular case, it is likely that the present owner/operator of this aircraft was either not aware of this particular Technical Bulletin or did not do a thorough review of the aircraft history at the time of purchase to see what OEM bulletins had been incorporated.

Transport Canada recommends that owners of used rotorcraft be aware of what manufacturers' recommendations have not been incorporated.

Further similar occurrences or any other defect, failure or malfunction should be reported by sending a Service Difficulty Report (SDR) to Transport Canada, Continuing Airworthiness, Ottawa.

For further information, contact a Transport Canada Centre, or Mr. Barry Caldwell, Continuing Airworthiness, Ottawa, telephone (613) 952-4358 or facsimile (613) 996-9178 or e-mail

For Director, Aircraft Certification

B. Goyaniuk
Chief, Continuing Airworthiness