On August 14, 1990, a Bell 47 D-1 (registration N3656F) operated by Allied Helicopter Service, Inc was involved in an aviation accident near Stockbridge, MI. Investigators recorded the probable cause as: THE RESTRICTED VISUAL LOOKOUT WHICH RESULTED FROM THE CANOPY FOGGING UP. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 1 related events involving the same aircraft type or operator are linked below.
An agricultural helicopter on a re-positioning flight experienced complete canopy fogging after takeoff, collided with a power pole, ruptured fuel tank, and was destroyed by fire.
Incident Overview
An agricultural helicopter was destroyed by fire after a collision with a power pole and wires during an early morning re-positioning flight. The accident occurred shortly after takeoff when the canopy became completely fogged over. Before the pilot could re-orient by looking through the side opening, the helicopter struck a power pole and associated wires.
Sequence of Events
The helicopter had just departed on a re-positioning flight when the canopy fogged entirely. The pilot attempted to regain orientation by looking out the side opening but was unable to do so before the collision. The impact ruptured the fuel tank, spraying aviation fuel onto the hot engine and exhaust pipes. The resulting fire destroyed the helicopter.
Damage
The helicopter was consumed by fire following the fuel ignition. No further details on damage are available from the source.