2000-01-14: ARN841 DH8
enroute Moncton to Halifax reported # 2 Engine Failure 15 nm North of Halifax. Due to weather considerations pilot request divert to Saint John. While enroute to Saint John the Engine was restarted and flight landed Halifax without further incident 1316z. TSB evaluating. Update: Examination of the engine revealed that ice had accumulated in the intake plenum just forward of the diffuser. It is suspected that a piece of ice may have broken off and been ingested in the engine causing the flame out. An inspection of the # 1 engine intake revealed an ice build up in the same area. Three other company aircraft were inspected and ice was found to have accumulated in the same area on all three aircraft. The aircraft had been brought out of the hangar in the morning, maintenance preformed an engine ground run and the aircraft was then placed at the gate. The crew and passengers boarded and the aircraft taxied from the gate to the de-icing bay and then positioned for take-off. The total taxi time was reported to be about one hour and heavy wet snow was falling throughout this time. The flight to Moncton was uneventful as was the return flight to Halifax up to the time that the engine flamed out. The movement history of the other three aircraft that morning is not known. Prior to the occurrence the company winter operating policy was to have the engine intake bypass doors open at all times except during push back. The reason for not having them open during push back was because the engines were operating with the props in feather and the theory was that in this configuration the possibility existed that FOD may be sucked into the engine through the bypass doors. Since this occurrence the company has re evaluated this policy and have issued a crew alert advising crews to keep the bypass doors open at all times. The crew alert also calls for a mandatory tactile inspection of the engine intake in the area forward of the bypass door. This inspection is to be carried out at all station stops when icing conditions exist. The operator has documented two other incidents where ice ingestion is the suspected cause of engine flame outs. As well, a query in ASIS
(TSB data program) has revealed two occurrences where ice ingestion has been suspected of causing engine flame outs. Reference A87O4219 and A97A0080. End. TSB file # A990160 Regional Follow UP: Cador 1999A0670 MAH & MAB carried out an investigation of this incident. Additional information has been filed in the CADOR records for the Atlantic Region and can be made available to other branches if required.