On September 27, 2003, about 1330 eastern daylight time, an amateur built Pitts S1S, N465JW, was substantially damaged while landing at Chestnut Hill Airport (5PS5), Duncannon, Pennsylvania. The certificated commercial pilot was not injured. Visual meteorological conditions prevailed for the flight that departed Keller Brothers Airport, Lebanon, Pennsylvania. No flight plan was filed for the personal flight conducted under 14 CFR Part 91. Chestnut Hill Airport was serviced by runway 7/25. The runway was 1,700 feet long, 100 feet wide, and consisted of turf. The pilot stated that he initially flew over the airport to check the wind and field conditions. He estimated that the wind was from the south, and he decided to land on the east runway. The approach to runway 7 was uneventful; however, the airplane encountered a wind gust prior to touchdown. The airplane initially touched down, but a second gust of wind forced it back into the air. The airplane touched down a second time, and was not aligned with the runway. The airplane subsequently veered left and began to travel off the left side of the runway. The pilot applied right rudder and brake, but was unable regain directional control. The airplane continued to travel off the left side of the runway and came to rest upright. The wind reported at an airport about 10 miles southeast of the accident site, at 1356, was from 160 degrees at 12 knots. The pilot reported that the wind at the accident site was from 160 degrees at 16 knots, gusting to 25 knots. The pilot reported a total flight experience of 770 hours; of which, 85 hours were in the same make and model as the accident airplane. Examination of the airplane by a Federal Aviation Administration inspector revealed damage to right wing and landing gear. The inspector did not observe any pre-impact mechanical malfunctions, nor did the pilot report any.