Two-dimensional descent through a compressible atmosphere: Sequential deceleration of an unpowered load

Department of Physics, Trinity College - Hartford, CT 06106, USA

Corresponding author: mark.silverman@trincoll.edu

Received: 1 December 2009
Accepted: 1 February 2010

Abstract

Equations, based on Rayleigh's drag law valid for high Reynolds number, are derived for two-dimensional motion through a compressible atmosphere in isentropic equilibrium, such as characterizes the Earth's troposphere. Solutions yield horizontal and vertical displacement, velocity, and acceleration as a function of altitude and ground-level temperature. An exact analytical solution to the equations linearized in the aero-thermodynamic parameter is given; in general the equations must be solved numerically. The theory, applied to the unpowered fall of a large aircraft stabilized to flat descent by symmetrical, sequential deployment of horizontal and vertical decelerators, shows that such an aircraft can be brought down with mean peak deployment and impact decelerations below 10g.