Blue Water Aviation Services accident at Long Haul Lake

The Blue Water Aviation Services accident at Long Haul Lake occurred on 25 June 1999. On a test flight departing from and returning to Long Haul Lake in the Canadian province of Manitoba, a float-equipped De Havilland Canada DHC-3 Otter of Blue Water Aviation Services crashed. A technician was killed in the accident.

Sequence of the accident

On the morning of the accident, six passengers with baggage boarded the aircraft, which was to operate a regional flight to Sassiginak Lake. Before takeoff, the pilot drained the fuel tank sumps. He did not use a cup to examine the fluid more closely, but judged by feel that it was fuel. He started the engine and could not detect any anomalies. The flight to Sassiginak Lake was uneventful. After the passengers had disembarked, the pilot flew the aircraft on to Long Haul Lake. During the flight to Sassigniak Lake and for most of the flight to Long Haul Lake, the aircraft drew fuel from the front tank. Shortly before landing on Long Haul Lake, the pilot switched the tank valve to the centre tank.

During the stop on Long Haul Lake, eight passengers with baggage boarded; an onward flight to Matheson Island, Manitoba was planned. During the takeoff run, shortly before liftoff, the engine abruptly lost power. The propeller was turning, but the engine was operating at idle level. The pilot shut down the engine, the aircraft's speed decreased and it drifted to the shore of the nearest island. At that point it was unclear whether the engine had failed completely or had continued running at idle.

The pilot consulted with his airline. Thereupon a maintenance coordinator and a mechanic (who was also a pilot for the airline) loaded another aircraft with spare parts and tools and flew to Long Haul Lake. There, the passengers with their baggage transferred to the aircraft that had arrived, while the mechanic stayed with the pilot at the disabled aircraft. The two men tried to find out the cause of the loss of power during the takeoff attempt. After making sure that fuel supply was available, the pilot started the engine, ran it at idle and then gradually increased power. In a higher power range, he noticed the engine running rough, and in addition there was one backfire. Subsequently, the water separator sumps of the carburettor, the fuel tank and the fuel filter were drained. About a cup of water was drained from the fuel filter sump in the process.

Following this, the aircraft fuel was fed to the engine using the electric fuel pump and a test run was carried out. The two men were satisfied with the running of the engine and surmised that the previous rough running had been due to water in the fuel system. They then decided to carry out a test flight. During this, the fuel valve was still set to the centre tank. The engine initially ran smoothly and at full power during takeoff and in the initial climb. At a height of 100 to 150 feet the engine suddenly failed. The pilot tried in vain to restart the aircraft's engine until the Otter clipped some treetops and then crashed to the ground at a steep angle. The technician was killed in the accident; the pilot survived with injuries. After the impact, a small fire broke out in the area of the carburettor, but it went out shortly afterwards.