Mooney M20F N6878V accident near Copake, New York

Probable cause

The pilot's failure to monitor and maintain clearance from mountainous terrain during a visual descent to the destination airport at night, which resulted in controlled flight into terrain.

NTSB analysis

The airplane was approaching the destination airport in night visual meteorological conditions, on an instrument flight rules (IFR) flight plan. The destination airport was at an elevation of 739 feet mean sea level (msl), located in the vicinity of mountainous terrain. About 10 miles from the destination airport, the pilot elected to cancel his IFR clearance. At that time, the airplane was at 3,900 feet msl and began a descent consistent with a 45-degree entry to a left downwind leg of the destination airport traffic pattern, which was 1700 feet msl. About 2 minutes later, the airplane had descended to 2,400 feet and was approximately 1/4 mile from the 2,000-foot summit of a mountain. About 10 seconds later, the airplane had descended to 2,100 feet, about 1,000 feet horizontally from the summit. The airplane impacted trees near the summit and came to rest about 500 feet beyond the initial impact. The summit was approximately 5 miles southwest from the destination airport. Examination of the wreckage did not reveal any preimpact mechanical malfunctions. The end of civil twilight occurred about 2 hours prior to the accident. Moonset occurred about 1 hour after the accident and the phase of the moon was waxing crescent with only 22 percent of the moon's visible disc illuminated.

Text from the NTSB. Open the NTSB docket for ERA11FA055 for the full record.