Accident Overview
A pilot attempted a takeoff from a gravel river bar. Based on his estimate of the available distance, he judged 750 feet to be adequate for departure. The airplane was configured with 20 degrees of flaps for the takeoff. During the takeoff roll, the airplane settled into the river and subsequently nosed over.
Aircraft Performance Considerations
Published short-field takeoff performance data indicates that an airplane weighing 3300 pounds requires approximately 740 feet of ground roll on a smooth paved surface at a temperature of 15°C. The aircraft in this event was equipped with extended wing tip fuel tanks under a supplemental type certificate (STC), which increased the maximum gross weight by 200 pounds.
Takeoff Conditions
The pilot reported that the takeoff surface was a gravel river bar. No other information regarding surface condition, wind, or temperature was provided. The airplane was operated with 20 degrees of flaps, a setting commonly used for short-field takeoffs.
Outcome
After settling into the river, the airplane nosed over. No further details about injuries, damage, or the aircraft's subsequent condition were included in the report.