Primary finding
Probable cause
the pilot's failure to maintain an adequate glide path.
Investigator assessment
Analysis narrative
The pilot was beginning to deploy his dive brakes over the runway when he when he encountered thermal activity. The aircraft dropped, struck the runway, and then bounced back into the air. After touching down a second time, the aircraft slid to a stop on the runway. The pilot reported the conditions were clear and calm.
Source record
Factual narrative
On March 18, at 1400 hours mountain standard time, a Hoffmann Super Dimona HK 36R motor glider, N351HK, was destroyed during a hard landing at the Scottsdale, Arizona, airport. Neither the pilot nor his pilot rated passenger was injured. The aircraft was being operated as a personal flight by the pilot/owner when the accident occurred. The local flight originated from Scottsdale, Arizona, at 1357. Visual meteorological conditions prevailed and no flight plan was filed. The pilot stated that he was on climb out after departure from Scottsdale airport when he noted that his voltmeter was indicating a discharge. Deciding to return, he contacted the control tower operator and was cleared to land on runway 21. He said he was beginning to deploy his dive brakes, about 20 feet above the runway, when he encountered thermal activity. The aircraft dropped, struck the runway, and then bounced about 30 to 40 feet back into the air. After touching down a second time, the aircraft slid about 100 to 150 feet before coming to a stop on the runway. The pilot reported the conditions were clear and calm at the time. A postaccident inspection revealed the landing gear collapsed, the propeller was damaged, the canopy was cracked, the engine mounts were broken, and there were cracks and tears in the fuselage and wings. -