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It could be seen from the initial impact marks that the aircraft was in level flight longitudinally with an angle of bank to the right of less than 10 degrees when it struck the trees growing on the 35-degree slope, at an elevation of 3,140 feet near the crest of the mountain. As it continued into the trees, parts separated and finally the outer right wing panel was severed by another tree. The remainder of the aircraft continued over the crest of the hill without hitting the ground. Its forward motion was then stopped by contact with several large trees and it fell to the ground in an upright position. The cabin section of fuselage with the empennage attached then rolled 180 degrees to the right and came to rest inverted across the stub of the right wing.
The left engine separated from the aircraft during the impact sequence and came to rest at the crest of the ridge. The left propeller and nose section had broken away from the engine and had fallen about 20 feet back along the crash path. The right propeller separated during the first 135 feet after initial impact and came to a stop about 35 feet behind the main wreckage. The right engine continued forward when the aircraft was stopped by the large trees and came to rest about 300 feet down hill from the wreckage.
An intense fire ensued in the main wreckage consuming the nose section, cabin sides and belly of the fuselage, the nacelles, and forward part of the wing center section. Inasmuch as there was no evidence of fire or heat on the trees, underbrush, or pieces of wreckage along the crash path, this fire must have occurred after the wreckage stopped.
All components of the aircraft structure were accounted for in the wreckage area. All control surface hinges and control surface bell cranks were located and all damage was determined to have been the result of impact forces. The control system cables were traced and found to be intact with the exception of those points at which the outer wing panels had separated. The landing gear and flaps were in the fully retracted position and, as near as could be determined, all trim tabs were in the neutral position.
The left propeller was found almost at the top of the ridge. It had broken from the engine at the nose section and had lodged in an upright position against a tree. All three blades remained attached to the hub but were bent at various angles and about eight inches of the tip of the No. 1 blade was broken off. The propeller dome shell was broken and the piston was partially collapsed by a load on its forward end. Upon disassembly the low pitch stops were found to be crushed by the rotating cam stops at impact. The dome piston was at 24 degrees. Only one of the three blade shim plates bore markings sufficiently distinct for blade angle correlation. It indicated a blade angle of 24 degrees at impact.
The left engine was found lying on its nose section near the crest just a few feet from its propeller. Two cylinders and rocker assemblies were broken away from the engine by impact. The power section was inspected and was found to have had adequate lubrication. There was no evidence of abnormal heat discoloration, flailing, or interference of the moving parts. The nose case was broken open and the reduction gears were separated from the engine. They appeared normal and adequately lubricated. All engine accessories were examined and no evidence of operating difficulty was found.
