On May 25, 2007, at 0810 central daylight time, a Champion 7EC, N9904Y, collided with the terrain following a loss of control during takeoff from a private airstrip in Sioux Falls, South Dakota. The commercial pilot and passenger were not injured. The airplane was substantially damaged. The 14 CFR Part 91 personal flight was operating in visual meteorological conditions without a flight plan. The flight was originating at the time of the accident with a destination of Pipestone, South Dakota. The accident occurred on the pilot's 1,000 foot long private grass airstrip. The pilot reported that the winds were calm when he landed approximately one hour prior to the accident. He stated he checked the windsock prior to takeoff and it was indicating that the winds had increased and there was a left crosswind. The pilot reported the wind at the south end of the runway was stronger than what the wind sock was indicating, and the airplane veered to the right on takeoff because he "...did not correct adequately for the wind." The pilot reported that his altitude was lower than normal and he pulled up to avoid a fence at the end of the property. He stated the airplane stalled and the nose dropped. The airplane impacted the terrain and came to rest about 60 feet from the right side of the airstrip.