According to the pilot, he was completing a short cross-country flight and planned a practice short field landing at the destination airport. He landed on his planned touchdown point, but did not take the height of the runway threshold lights into consideration. During the final approach, the airplane struck the approach lighting system at the 400 and 600-foot positions from the runway end. An inspector from the Federal Aviation Administration examined the airplane and confirmed substantial damage to the lower surface of the fuselage, including both wing bulkheads. The pilot reported no pre-impact mechanical malfunctions or failures with the airplane that would have precluded normal operation. The runway had a 413-foot-long displaced threshold and the touchdown occurred near the front edge of the threshold.