On October 30, 1996, at 1040 hours mountain standard time, a homebuilt experimental Leibert BD-5B, N169DS, was substantially damaged during a forced landing attempt near the Williams Gateway Airport, Phoenix, Arizona. The forced landing was precipitated by a loss of engine power in the takeoff initial climb while the pilot was performing touch-and-go traffic pattern operations. Visual meteorological conditions prevailed at the time and no flight plan was filed. The certificated commercial pilot, the sole occupant, sustained serious injuries. After the loss of engine power the aircraft attempted to land in flat desert terrain and the landing gear was ripped out of the airplane as it touched down in the soft soil. The aircraft then cart-wheeled coming to rest about 1 1/2 miles west of the air traffic control tower. Responding bystanders and fire personnel stated that fuel was leaking from the aircraft as they arrived. During his rescue and extrication from the aircraft, the pilot told the bystanders that the Rotax engine overheated and quit. A responding Federal Aviation Administration inspector stated that on his arrival several hours after the accident, the coolant temperature gage was pegged above the redline limit. The inspector reported that the cylinder interiors exhibited evidence of high heat. No determination was made regarding the cooling system.