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Full Size Experiments

When performed in connection with a wind tunnel, or based on dependable data from other sources, full size wing tests are very instructive and useful if care is taken to have the tests conducted under uniform and known conditions. Many full size experiments of this nature have been carried out by Saint-Cyr University in France, and by the Royal Aircraft Factory in Great Britain. Both of these institutions have a wind tunnel and an almost unlimited fund of performance data, and last but not least, have the services of skilled observers.

At Saint-Cyr, the full size wings, or the entire machine, are carried on an electric car or "chariot." The speed of the car, the lift and drag, can be determined at any moment during the run through suitable recording devices. Actual flying tests have also been made, the measurement of the propeller thrust giving the drag, while the lift is known as being equal to the weight of the machine. The R.A.F. have carried out a very extensive series of flight tests, the experiments on the old "B. E.-2" probably being the best known.