Incident Overview

Description
Prior to a scheduled 07:20 departure, the flight and cabin crew of Delta flight 1490 completed their pre-flight duties and checks. The first officer would act as the pilot flying during the flight to Spokane. Before-start checks were completed without incident. Delta Flight 1490 received its IFR clearance to Spokane, and, at 07:18, the aircraft was instructed to taxi to runway 08 and to await takeoff clearance. At 07:28, Flight 1490 was cleared to take off and to contact Departure Control after takeoff. The initial takeoff roll was uneventful until the airspeed reached between 100 and 110 knots. At that time, the flight crew heard a loud bang, and the aircraft veered slightly to the left. The takeoff was rejected, and the aircraft was brought to taxiing speed as it approached taxiway Whiskey. ATC personnel then queried Flight 1490 about the presence of smoke on the left side of the aircraft. After confirming with the captain that the left engine had failed, the first officer shut down the engine and activated the left engine fire extinguisher system. The aircraft was taxied off the 200-foot-wide runway onto taxiway Whiskey, where it was brought to an immediate stop. The captain then ordered an emergency evacuation on the right side of the aircraft. PROBABLE CAUSE: “The Canadian Aviation Safety Board determined that the left engine combustion chamber outer casing ruptured as a result of a fatigue-generated crack which originated at a rear flange bolt hole. Crack initiation was most probably a result of the deposit of plating material in the bolt hole during overhaul of the case, contrary to the engine manufacturer’s rework instructions. Contributing to the occurrence was the failure of existing inspection procedures to detect the fatigue cracking.”
Primary Cause
Fatigue-generated crack in the left engine casing, originating from a rear flange bolt hole, caused by deposit of plating material during overhaul of the case.Fatigue-generated crack in the left engine casing, originating from a rear flange bolt hole, caused by deposit of plating material during overhaul of the case.Share on: