dependent on the mean velocity of the wind, and the exposure of the anemometer. It is a well known fact that wind velocities can fluctuate as much as 100%. For example, a wind velocity of 30 m.p.h. could range between 15 and 45 m.p.h in gustiness.
Condition of the Wreckage
The aircraft struck the windrow while skidding broadside at an estimated speed of about 20 m.p.h. Almost instantly the propeller tips struck the ground, tearing both propellers and nose section from the engines. Inspection disclosed that twelve inches of one propeller tip was broken off and all blades were badly bent. The left propeller struck the ground, broke free from the engine, then cut into the side of the fuselage at the pilots' compartment, severing the control column before coming to rest in the front of the plane. The right propeller broke free, struck the right side of the fuselage, just aft of the co-pilot's seat, cut a hole about 18 inches long in the side of the pilots' compartment, and came to rest about 400 feet to the right and slightly ahead of the plane. The brakes and all controls were found to be normal and in an operative condition. There was no indication of any mechanical failure of the aircraft or engines prior to impact.
Conduct of the Flight
The evidence indicates that the flight was properly dispatched and that its operation was normal until it arrived at Bismarck. Weather conditions were above the prescribed minimums. Neither the captain nor the operator considered the strong cross-winds, which were variable in direction and velocity, as being unsafe for landing under the existing conditions. The weather encountered during the landing approach, and the first part of the landing run, was substantially as reported by radio to Captain DeLong.
