A general introduction is presented to the longitudinal motion of aircraft over an extended range of angle of attack, and various aspects were investigated of the low-speed-deceleration maneuvre with excursion of very high angles of attack in the case of failure to recover. The entry into such flight conditions of two distinct types of aircraft-one with a wing of moderately large aspect-ratio and having a high tailplane, the other, a tailless slender aircraft-is considered in some detail by examining the effect of various inputs on the motion. The factors influencing the ease with which control of the aircraft may be regained were studied particularly in cases in which normal recovery was achieved by forceful recovery action and those in which the aircraft only recovers after an excursion to extreme angles of attack. The possibility of recovery is found to depend on the general nature of the motion under the action of markedly nonlinear aerodynamic forces and moments. For aircraft having pitching-moment characteristics like those of the subject aircraft, 9three types of motion can follow an attempt at recovery. There can be a reduction to two or even one as out-lined in the appendix. The problem of the stability of these motions was investigated. Examination of the allied single degree-of-freedom motion in pitch provides much insight into the more general problem, while phase-plane and similar three-dimensional plots prove useful means of displaying and interpreting results. The effect of varying the aircraft characteristics was examined. Various forms and levels of damping are considered as well as the more evident effects of the center-of-gravity position and the inertia-in-pitch of the aircraft. (Author)
Longitudinal Motions of Aircraft Involving High Angles of Attack
1974
100 pages
Report
Keine Angabe
Englisch
Aircraft aerodynamics at high angles of attack
NTRS | 1977
|Problems of Aircraft Behaviour at High Angles of Attack
NTIS | 1969
|