Wind Tunnel Investigation Of Effect Of Sweep On Rolling Derivatives At Angles Of Attack Up To 13 And At High Subsonic Mach Numbers Including A Semiempirical Method Of Estimating The Rolling Derivatives

An investigation was performed in the Langley high-speed 7- by 10-foot tunnel in order to determine the rolling derivatives for swept-wing-body configurations at angles of attack from 0 degrees to 13 degrees and at high subsonic Mach numbers. The wings had sweep angles of 3.6 degrees, 32.6 degrees, 45 degrees, and 60 degrees at the quarter-chord line, an aspect ratio of 4, a taper ratio of 0.6, and an NACA 65A006 airfoil section parallel to the free stream. The results indicate a reduction in the damping-in-roll derivative at the higher test angles of attack. Of the wings tested, instability of the damping-in-roll derivative was experienced over the largest ranges of angle of attack and Mach number for the 32.6 sweptback wing.

A theoretical analysis was made to investigate the performance and acceleration-restriction capabilities of a normal-acceleration command control system in a fighter airplane. Several combinations of pitching velocity and pitching acceleration were investigated as feedback quantities in combination with normal acceleration.

Stability and Control of Airplanes and Helicopters deals with aircraft flying qualities that determine the stability and control of airplanes and helicopters. It includes problems based on real aircraft, selected to represent the gamut from simple to complicated, and from conventional utility designs to futuristic research types. Many of these problems involve comparison of theory and experiment to demonstrate their mutual relationship. Comprised of 25 chapters, this book begins with a discussion on the aerodynamics of the component parts related to the lift and moment characteristics of an airplane, including wings and associated accessories; bodies such as fuselages, nacelles, and tip tanks; and control surfaces. The reader is then introduced to some mathematical techniques for linear differential equations; steady flight at different speeds; and stick force and control-free stability. Subsequent chapters focus on flaps and high-lift devices; power and compressibility effects; and the manner in which the aircraft responds to the application of control. Aeroelasticity and longitudinal equations of motion are also examined. This monograph is intended for undergraduate and graduate students taking modern engineering courses.