FAA notes engine mount failure risk on some Bell helicopters

In an Information for Operators notice,  the FAA recommended that operators and repair facilities “be aware of and reduce the risk of possible accidents caused by corrosion,” and “pay close attention to the engine mount areas and associated components during inspections for signs of corrosion.” There are 201 BHT-206L1 and 203 BHT-206L3 aircraft registered in the United States.

In 2014 a Part 135 helicopter air ambulance operator conducted a fleet inspection of the engine-mount leg assemblies on all its Bell Helicopter 206Ll and 206L3 aircraft after an engine change revealed that a steel engine-mount leg was corroded from the inside and cracked, the FAA said. The inspection determined that “28 of the operator’s aircraft used the same type of steel construction for the engine mount leg assemblies.”

In response to the report, Bell Helicopter issued an Operational Safety Notice on Jan. 21, 2015. The manufacturer has replaced the steel used for the affected parts with corrosion-resistant steel, the FAA said.

The agency reviewed the Service Difficulty Report database for the affected parts and identified “11 reports specifically related to engine-mount leg-assembly failure due to corrosion,” the FAA said.