The performance of an aircraft in the hands of a competent pilot — at a given altitude — results from the sum of power, angle of attack, attitude and configuration. Power provides thrust and consequently contributes to acceleration, airspeed, lift, drag and radius of turn. The angle of attack dictates the dimensions of the lift force and the induced drag and contributes to airspeed; also the angle of attack is a significant contributor to the aircraft attitude. Attitude is the angle the aircraft longitudinal axis subtends above or below the horizon (usually called the ‘pitch’ which has another meaning associated with propellers) plus the angle of bank and the degree of slip. Attitude dictates the direction of the lift, thrust and drag vectors and, consequently, converts power into velocities and accelerations in the three planes. Configuration relates to the deployment of lift/drag changing devices.
Airspeed is dependent on power, angle of attack, configuration and attitude — under any given set of conditions — and attitude in flight is readily checked by reference to the horizon. The lift, thrust and drag forces produce manoeuvring loads on the aircraft structure, generally expressed in terms of ‘g’, that must be kept within defined limits. There is a fourth performance factor — energy management — which is an art that supplements attitude plus power plus height to produce maximum aircraft performance. The epitome of such an art is demonstrated by air-show pilots who produce extraordinary performances from otherwise relatively mundane aircraft. Continue reading Post ID 364