On July 16, 2003, about 1305 eastern daylight time, a Piper PA-34-220T, N5359J, piloted by a private pilot, was substantially damaged during a hard landing on runway 28 (4,001 feet by 75 feet, asphalt), at the St. Clair County International Airport (PHN), near Port Huron, Michigan. The 14 CFR part 91 business flight was operating in visual meteorological conditions. The pilot was not injured. The flight originated from the Flying Cloud Airport, Minneapolis, Minnesota, at 0915. In a written statement, the pilot stated that he made a normal left-downwind approach for runway 28 at PHN. He indicated that all airspeeds on downwind, base, and final were normal. At touchdown of the main landing gear, wind gusts changed and caused the airplane to bounce off of the nose gear. The pilot attempted to settle the airplane back on the main gear, but it bounced higher and continued bouncing at least three more times veering to the left and in the grass. The airplane then continued to roll back to runway 28 and eventually came to a stop at the run-up area of runway 10. The recorded weather at PHN at 1316 was: Winds: 330 degrees at 6 knots Visibility: 10 statue miles Sky condition: clear Temperature: 23 degrees Celsius Dew Point: 16 degrees Celsius Altimeter: 30.06 inches of mercury The pilot reported having autopilot altitude hold problems during the en route portion of the flight. However, he reported no anomalies with the primary flight controls.