Author: Jim A. Penland

Publisher:

Published: 1956

Total Pages: 31

ISBN-13:

Results are presented of three-component force tests of a cylindrical body with an ogival nose equipped with panel-type drag brakes each covering approximately 21 percent of the body circumference and located on opposite sides of the body at the rear end. The investigation was made in the Langley 11-inch hypersonic tunnel at a Mach number of 6.86, a Reynolds number of 1,500,000 based on body length, angles of attack from -5 to 25 degrees, and brake-deflection angles from 0 to 30 degrees, with the brakes in the vertical and horizontal planes. The comparison of experimental results with the results of Newtonian impact theory shows that the trends of the longitudinal characteristics with angle of attack may be predicted with reasonable accuracy. The drag brakes in the vertical position produce higher total drag and higher negative pitching moments at angles of attack than do the identical brakes in the horizontal position, even though the top drag brake becomes ineffective at high angles of attack.