Narrative:Flight 115 originated at Minneapolis, Minnesota, for Seattle, Washington, with several scheduled stops including Billings, Montana, and Spokane, Washington. It departed Minneapolis at 01:10, on schedule, made two planned stops, and arrived at Billings at 05:12, eight minutes behind schedule because of head winds.
At Billings the crew was changed. Departure from Billings was at 05:40, twenty-five minutes late because of ramp congestion. The flight made intermediate stops en route to Kalispel, Montana, without reported incident Between Kalispel and Spokane it radioed that oil temperature in the right engine was high, but shortly radioed that the oil temperature had dropped to normal Landing at Spokane was at 11:22, fifty-two minutes late due to head winds and station delays. Water was found in the right engines oil cooler air scoop, the high oil temperature was attributed to the temporary presence of ice or snow in that scoop.
At Spokane the aircraft was checked visually, and departed at 12:04 on an IFR flight plan to cruise at 6,000 feet MSL between Spokane and Wenatchee, Washington. The flight reported having reached the cruising level of 6,000 feet MSL at 12:07. At 12:12 it was given the Wenatchee weather which was below minima. The flight immediately asked clearance to the next scheduled stop, Yakima, where the weather was above minima. While the Spokane radio operator was obtaining the requested clearance, the flight broadcasted an emergency message. This was at about 12:13, only some 15 seconds after asking for the new clearance. No difficulty of any sort had been reported previously. The plane had lost control and struck the ground which was at an altitude of 2,310 feet MSL in a nose-down attitude of about 45 degrees and with its right wing low.
PROBABLE CAUSE: "The Board, after extensive study of all evidence determines that the probable cause of this accident was a sudden loss of control for reasons unknown, resulting in rapid descent to the ground."
» CAB File No. 1-0004
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 Spokane-Geiger Field, WA to Wenatchee-Pangborn Field, WA as the crow flies is 201 km (125 miles).