EFFECT OF GROUND PROXIMITY ON THE AERODYNAMIC CHARACTERISTICS OF A FOUR-ENGINE VERTICAL-TAKE-OFF-AND-LANDING TRANSPORT-AIRPLANE MODEL WITH TILTING WING-AND PROPELLERS

摘要

An investigation has been made to study the effect of ground prox-imity on the aerodynamic characteristics of a four-engine vertical-take-off-and-landing transport-airplane model with tilting wing and propel¬lers. Tests were made with the wing at an angle of incidence of 90°, the position used for vertical take-off or landing. With the model at various heights above the ground, the lift, drag, and pitching moment were measured and tuft studies were made to determine the flow field caused by the propeller slipstream. Data were obtained for the complete model, for the model with horizontal tail removed, and for the wing-propeller combination alone.