Redmond Twin Otter Aircraft Accident Fatality 1988

Pilot David Schas was killed when the DHC-6 Twin Otter he was flying solo crashed in mountainous terrain in western Grant County, Oregon. Schas was scheduled to make stops at John Day and Pendleton, Oregon, to pick up fire personnel and take them to Miles City, Montana, to help support wildland fire operations there. Schas contacted dispatch via radio to check in and report his ETA at around 1135, but was not heard from again. It was determined that between 1140 and 1142 the aircraft's right wing impacted three trees at about 5,000 ft elevation. The aircraft then impacted a 5800 ft elevation ridge and finally came to a rest in a steep canyon. The aircraft had flown off-course for the 5 minutes between the last radio communication and the impact, and descended into the terrain. The exact cause of the crash is unknown, but may have been due to pilot incapacitation, possibly from falling asleep.