The effect of the wings of single engine airplanes on propulsive efficiency as shown by full scale wind tunnel tests

Fred E. Weick, Donald H. Wood
Oct 1929

An investigation was conducted to determine the effect of the wings on propulsive efficiency. The wings are shown to cause a reduction of 1 percent to 3 percent in propulsive efficiency, which is about the same for monoplane as well as biplane wings.

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