AS350 SBs and the NTSB
NTSB Wants SBs Required for AS 350 Series
Investigations into two accidents involving Eurocopter AS 350A and AS 350B2 helicopters led the NTSB to determine that the hydraulic pump drive belt (P/N 704A33690004) prematurely failed in flight. Additionally, an inquiry into the FAA’s Service Difficulty Report database found that 43 failures and/or replacements of hydraulic pump drive belts with that part number occurred from February 1995 to the present. Eurocopter issued Service Bulletins in 2002 that offered an improved drive belt, as well as recommending replacing the hydraulic pump drive pulleys and pulley bearings. According to Eurocopter, about 272 pump-belt-conversion kits have been sold to U.S. operators. About 460 AS 350 series helicopters are currently in operation in the U.S. Therefore, the NTSB recommends that the FAA require operators of these helicopters to comply with the Service Bulletins.