Stanwood W. sparrow
The aim was to bring attention to what might be the cause of some aircraft accidents for which there was no satisfactory explanation. The author notes that in testing aircraft accidents at the Bureau of Standards, it happened frequently that the engine performance became erratic when the temperature of the air entering the carburetor was between 0 C and 20 C. Investigation revealed the trouble to have been caused by the formation and collection of snow somewhere between the entrance to the carburetor and the manifold, probably at the throttle. Proof scarcely less convincing was obtained during engine tests. The results of such engine tests are described. Granting that the loss of power and the sudden increases in power were caused by the condensation of moisture from the air and the subsequent formation of snow, two solutions proved effective. The removal of the moisture or an increase in temperature cured the problem.
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