Page:Aerial Flight - Volume 1 - Aerodynamics - Frederick Lanchester - 1906.djvu/398

§ 244 § 244. Method of Total Surface.—Mica Aerodone. Series E., No. I. Fig. 155.

This aerodone was one of a series of models specially designed for the purpose of measuring $$\xi$$ by the method of total surface. The supporting member is an aeroplane whose angle to the line of flight is determined by a pair of tail planes whose sole function is directive. It may be noted that the tail planes are so placed as to be influenced equally by the downward and upward