On October 4, 1993, at 1000 Alaska daylight time, a wheel equipped Piper PA-18 airplane, N81648, registered to Kurt Lepping of Wasilla, Alaska, and operated by Damond Blankenship of Eagle River, Alaska, struck some brush after takeoff from a field site located 21.7 miles east of Port Heiden, Alaska. The personal flight, operating under 14 CFR Part 91, was departing the field site and the destination was Port Heiden. No flight plan was filed and visual meteorological conditions prevailed. The airplane was substantially damaged and the Private Certificated Pilot-in-Command and his passenger were not injured. According to the Pilot-in-Command, the wind was straight down the runway, blowing at 20 knots gusting to 25 knots. He made the takeoff roll uphill into the wind and lifted off near the end of the airstrip. The airplane settled and the left main gear struck some brush and spun the airplane around. The Pilot-in-Command stated the surface of the runway was very soft, and the main landing gear wheels, airstreak 30 inch tires, would sink into the surface 1 to 2 inches. He used full flaps for takeoff. During a telephone interview with the Pilot-in-Command, he stated the airplane was empty except for himself and the passenger and 10 to 15 gallons of fuel which was distributed equally between the fuel tanks. The Pilot-in-Command could not provide the empty weight of the airplane and stated, although he did not perform a weight and balance, he felt the airplane was under its gross weight. They were planning to fly to Port Heiden to pick up fuel.