Landing and Takeoff Preparation
An aircraft landed on a gravel bar in a wilderness area for hunting purposes. Two days later, the pilot estimated that approximately 1,400 feet of usable surface was available for takeoff. He elected to take off uphill to take advantage of a slight headwind condition in that direction.
Surface Conditions
The surface consisted of loose sand and gravel, with varying degrees of softness across the area.
Takeoff and Collision
During the takeoff roll, the aircraft became airborne in ground effect as it reached the end of the usable surface. At that point, a wind shift occurred, which precluded a climb away from rising terrain. The aircraft subsequently collided with a river cut bank.
Performance Calculations
Calculations indicate that a minimum of 1,580 feet of usable surface would have been required for this aircraft, with its load and under the existing conditions, to effect a safe takeoff.