November 3, 2012 - Cessna 172S N985GE at Northwest Regional Airport in Roanoke TX
From the NTSB report:
The student pilot was returning from a solo cross-country flight at the time of the accident. He stated that the approach for landing was normal until he was on short final approach, when the airplane's landing gear struck an automobile that was being driven on a road that crossed near the approach end of the runway. The airplane subsequently landed hard and the nose and left main landing gear collapsed. The airplane veered off the right side of the runway before coming to rest in the grass. The student pilot stated that there were no malfunctions or failures with the airplane before it impacted the vehicle. The automobile driver reported that he had been to the airport before and was aware of the proximity of the road to the runway, describing the layout as "precarious." He noted that he did not see or hear the approaching airplane traffic before the accident. He said he was about halfway across the road, immediately north of the runway, when he first heard the airplane engine; the airplane impacted his car immediately afterward.
The displaced threshold for the landing runway was located about 140 feet from the approach end of the runway. The roadway that crossed the extended runway centerline was located about 25 feet from the approach end of the runway pavement, about 165 feet from the displaced threshold. Data indicated that the runway threshold was previously displaced 400 feet. Although the privately-owned airport was not required to maintain airport design standards established by the Federal Aviation Administration, the proximity of the roadway and the reduced runway threshold displacement did not provide any safety margin for approaching aircraft.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The student pilot's failure to maintain clearance from obstacles on the runway approach path. Contributing to the accident was the airport management's decision to relocate the runway displaced threshold, which did not provide an adequate safety margin for approaching aircraft, and the automobile driver's inadequate lookout for approaching aircraft before crossing the runway's approach path.