Accident Flight
The pilot and five passengers departed Lac-à-la-Tortue for a local test flight. Ten minutes later, while flying at 2,100 feet, the engine failed. The pilot attempted an emergency forced landing on nearby Lake Mondor, apparently downwind. The aircraft first contacted the water near the middle of the lake, which was about three-quarters of a mile long. It bounced, then settled again about 200 feet from the east end, and continued onto the shore, where it struck trees and a small cottage, causing substantial damage. Two passengers sustained minor injuries.
Investigation
Examination revealed that the aircraft was equipped with a front belly tank in addition to the normal wing tanks. The placard plate for fuel tank selection did not indicate the presence of a belly tank. When the cockpit selector indicated 'both on,' the valve was actually selecting the belly tank. Several days before the accident, five gallons of gasoline had been placed in the belly tank during a leak test, and no additional fuel was added thereafter, although the wing tanks had been filled. On a test flight conducted on May 8, fuel was used from all three tanks. On the last flight of that day, only the belly tank was used. The pilot was unaware that the aircraft was fitted with a belly tank and believed that selecting 'both on' would feed from both wing tanks. After the accident, the belly tank was found empty and undamaged. There was no evidence of airframe, engine, or control failure or malfunction. Weather was not considered a factor.
Probable Cause
The official finding attributed the accident to fuel exhaustion from the belly tank, which led to engine failure and the subsequent forced landing. A contributing factor was the misleading placard on the fuel selector valve, which did not inform the pilot of the belly tank installation.