NTSB Wants an AD for Eurocopter AS 350s
Investigations into two accidents involving Eurocopter AS 350 helicopters led the NTSB to determine that the hydraulic pump drive belt (P/N 704A33690004) p

Investigations into two accidents involving Eurocopter AS 350 helicopters led the NTSB to determine that the hydraulic pump drive belt (P/N 704A33690004) prematurely failed in flight. Additionally, an inquiry of the FAA’s Service Difficulty Report database found 43 failures and/or replacements of hydraulic pump drive belts with that part number between February 1995 and the present. Eurocopter issued Service Bulletins in 2002 that offered an improved drive belt and recommended replacing pump drive pulleys and bearings. The NTSB wants the FAA to require compliance with the Service Bulletins.