Narrative:The Curtiss was chartered to fly military personnel from Seattle to Fort Jackson, SC. A scheduled stop was planned in Cheyenne. The flight departed Boeing Field at 00:50 and made the required position reports along the route, with no mention of any irregularities, reporting over Malad City at 13,000 feet, time 03:58, and estimating Rock Springs at 04:45. There were no further radio contacts with the aircraft. The C-46 started picking up some ice. It is likely that an involuntary descent was made into an area of increasing ice and turbulence which extended two or three thousand feet above the mountains. The mountains between Malad City and Bear Lake range from 8.000 feet to in excess of 9,000 feet. The westerly winds were lifting the moist unstable air over those mountains, producing zero ceilings, moderate to seven turbulence, moderate to heavy icing and snow, with updrafts on the windward side of the slopes and downdrafts on the leeward sides. The aircraft was unable to regain altitude until it struck a small pine tree at an altitude of approximately 8,545 feet. It struck several other pine trees and began to disintegrate as it continued down the slope at an approximate 50-degree angle shearing numerous trees. Contact with the ground was made at the base of the hill at the north end of a 93-foot ravine where the aircraft gouged three large holes in the ground. The aircraft then continued up a 32-degree rise approximately 200 feet where the tail section came to rest. Five days later, on January 12, 1953, at 1320 hours, the wreckage was sighted from the air by a Civil Air Patrol pilot.
Probable Cause:
PROBABLE CAUSE: "The inadvertent descent into an area of turbulence and icing which resulted in the flight's inability to regain a safe altitude."
Accident investigation:
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Investigating agency: | CAB  |
Status: | Investigation completed |
Accident number: | final report | Download report: | Final report
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Sources:
» CAB File No. 1-0006
» ICAO Accident Digest Circular 39-AN/34 (21-24)
Photos

accident date:
07-01-1953type: Curtiss C-46F Commando
registration: N1648M
Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does
not display the exact flight path.
Distance from Seattle-Boeing Field International Airport, WA to Cheyenne Airport, WY as the crow flies is 1545 km (966 miles).
Accident location: Approximate; accuracy within a few kilometers.
This information is not presented as the Flight Safety Foundation or the Aviation Safety Network’s opinion as to the cause of the accident. It is preliminary and is based on the facts as they are known at this time.