Incident Overview
A pilot was dispatched to a remote gravel airstrip at Toksook to pick up an undetermined number of passengers. Upon arrival, the pilot loaded the airplane with five passengers. To avoid a reported soft spot at the south end of the 1,800-foot runway, the pilot elected to take off to the north. The runway slopes uphill to the north with a gradient of approximately 2%.
Takeoff and Sequence of Events
During the takeoff roll, the airplane encountered a soft spot and decelerated. Despite the deceleration, the pilot continued the takeoff. Shortly after passing over the end of the runway, the airplane's right main tire struck a snow berm. The impact caused the right main tire and gear strut to separate from the landing gear. The flight continued to Dillingham, where a gear-up landing was made.
Weight and Balance Considerations
The pilot had estimated the airplane's takeoff weight at 6,200 pounds. However, an FAA inspector reviewed the flight's weight and balance data and computed the weight at 6,576 pounds. At this weight, the airplane's flight manual indicates that the airplane requires 2,200 feet for takeoff from a level, hard surfaced runway, and 2,100 feet when loaded to 6,200 pounds. The flight manual has no provisions for determining additional runway needed for takeoff from a soft, uphill runway.