1957-10-29: Boeing KC-97 Stratotanker (52-2711) — United States Air Force - USAF (since 1947) — Gray Mountain, United States of America

16 fatalitiesGray Mountain, United States of AmericaFlight

A four-engine aircraft crashed into a mountainside near Flagstaff, resulting in the deaths of all 16 people on board.

What happened

On the morning of the accident, the crew departed from Walker AFB at 0630LT to begin a scheduled nine-hour low-level survey training mission. While navigating through marginal weather conditions, the four-engine aircraft flew over the town of Gray Mountain at an altitude of approximately 60 feet.

During this phase of flight, the aircraft struck a mountain slope roughly 35 miles from Flagstaff. The force of the impact caused the plane to disintegrate. There were no survivors among the 16 fatalities recorded in the incident.

Findings

At the time of the collision, the area was experiencing low cloud cover which resulted in limited visibility for the crew. The flight was operating at a very low altitude during these difficult meteorological conditions.

Probable cause

Limited visibility due to low clouds and low-altitude flight through marginal weather led the aircraft into terrain.