Book Description

An approximate method for calculating climb and acceleration performance of an air-breathing aircraft has been developed. Basically, the method involves linearization of the equations of motion to obtain closed-form expressions for the desired performance parameters. These expressions are applied over finite velocity intervals where the aerodynamic, propulsion, and flight-path parameters are assumed to be constant. The method is extended by a rapidly convergent iteration procedure to estimate the climb performance for a flight path limited by sonic-boom considerations. Typical examples are presented where the performance is estimated for an air-breathing boost mission to hypersonic speeds and for a complete supersonic-transport mission. The examples illustrate the simplicity of the method and show that the estimated performance is in good agreement with the results of a numerical integration of the equations of motion. The application of the approximate method to these examples indicates the utility of the method for producing performance estimates suitable for preliminary airframe design, sizing studies, propulsion-system evaluation, and cursory heat-transfer and inlet-flow-field determinations along a flight path. In order to increase the utility of the method further, nomograms are presented which provide rapid solutions to the approximate performance equations.