On September 6, 1999, about 1130 Alaska daylight time, a Cessna 150 airplane, N63460, sustained substantial damage when it contacted brush during takeoff and initial climb from the Jewell Airstrip, at 61 degrees 43 minutes north latitude, 150 degrees 37 minutes west longitude, about 20 miles west of Big Lake, Alaska. The private pilot and sole passenger were not injured. The flight was being conducted under 14 CFR Part 91 as a personal flight in the local area. Visual meteorological conditions prevailed at the time of the accident, and no flight plan was filed. During a telephone interview with the NTSB investigator-in-charge on September 9, the pilot stated that during the initial climb after takeoff from the 1,350 feet long grass airstrip, the left wing contacted brush, the airplane pivoted 180 degrees, and the right wing struck the ground. The pilot said he was departing uphill, and the winds were five to ten knots. The pilot also indicated that the headwind stopped during the takeoff. The pilot estimated the airplane had 84 pounds of fuel on board. The Cessna 150 Takeoff Distance performance charts for 1,600 pounds takeoff weight, 20 degrees Celsius, and sea level pressure altitude, indicate the required ground roll is 765 feet, and the distance to clear a 50 feet obstacle is 1,435 feet. The chart provides a 10% reduction in distance for each 9 knots headwind, and a 15% increase in distance for dry grass. No correction is provided to account for the uphill slope.