What happened
The twin engine airplane departed Moncton on a ferry flight bound for Montreal with four crew members aboard. While cruising over the state of Maine, weather conditions deteriorated significantly. At that time, two other similar aircraft diverted to Millinocket, Maine, due to the conditions. However, the pilot of JS173 elected to continue the flight toward Montreal.
Despite the poor visibility, the pilot descended into instrument meteorological conditions. The aircraft impacted hilly terrain on Saddleback Mountain at an altitude of 2,690 feet. Three crew members were killed in the accident. The sole survivor managed to walk for several hours before receiving assistance. According to the survivor's account, the altimeter indicated a reading of 4,000 feet at the time of the event.
Findings
The official investigation determined that the crash was a controlled flight into terrain. This occurred following the pilot's decision to descend under instrument conditions in bad weather. The findings noted that the pilot should have been aware that the height of land along the course ranged from 500 to 5,000 feet. Consequently, flying at an altitude of 4,000 feet in such weather conditions was deemed unsafe.