What happened
On May 25, 1986, an aircraft was taxiing across frozen lake ice at Reliance, Northwest Territories, when the nose gear broke through a crack in the surface. Local residents attempted to stabilize the situation by using empty drums and pallets to prevent the airframe from submerging further.
As insurance investigators evaluated recovery options, the aircraft continued to descend into the water. The situation reached a point where only the tail section remained visible above the ice level. To resolve the incident, a military Chinook helicopter was sent to the site and managed to lift the de Havilland Canada DHC-6 Twin Otter from the lake. The crew placed the aircraft on the ice near a weather station to prepare for a long-distance sling load transport of 143 nautical miles to Yellowknife.
During the subsequent flight, approximately 200 yards after takeoff, the helicopter's load master decided to release the aircraft. This caused the plane to fall nose-first through the ice and back into the lake. While some components were recovered via barge to Yellowknife, the aircraft was declared a total loss.
Findings
- The initial incident was caused by the nose gear settling into a crack in the lake ice during taxiing.
- The secondary destruction of the aircraft occurred because the load master released the aircraft from the helicopter mid-flight.