The FAA proposes to adopt a new airworthiness directive (AD) for certain Honeywell TPE331-5, -5A, -5AB, -5B, -10, -10R, -10U, -10UF, -10UG, -10UGR, and -10UR turboprop engines. It was prompted by engine propeller shaft coupling failures, leading to unexpected propeller pitch changes and resulting in high aerodynamic and asymmetric drag on the airplanes using these engines. This proposed AD would require removing from service certain part number propeller shaft couplings.
British investigators are focusing on a fractured bevel gear vertical drive shaft as a contributing factor in the North Sea ditching of a Bond Offshore Eurocopter EC225LP Super Puma (G-REDW) 20 nm east of Aberdeen, Scotland, on May 10. The UK’s Air Accidents Investigation Branch (AAIB) issued a bulletin late last week on its preliminary findings.
Bell 206B JetRanger, Cleveland, Ohio, June 25, 2005–A failure of the main drive shaft for undetermined reasons, the NTSB concluded, caused the total loss of engine power in the Bell 206B JetRanger. A factor in the accident was the pilot’s improper flare.