Drag sail for end-of-life disposal from low Earth orbit

International standards are moving toward the requirement that spacecraft should be removed from orbit at the end of their operational lives. The feasibility of a deployable aerodynamically stable drag-enhancement structure is considered for the end-of-life disposal of low-Earth-orbit spacecraft, and how this structure could fulfill NASA deorbit guidelines is demonstrated. The concept is a thin membrane supported by deployed struts. A shuttlecocklike geometry is chosen to take advantage of the small stabilizing effect caused by oscillatory motion in, and descent through, the free molecular flow during deorbit. The shuttlecock is approximated to a cone, and the aerodynamic loads due to orbital and rotational motion are calculated and used to model the stabilization and descent of a deployed system toward final reentry. Finally, it is shown that this system can provide an effective and mass-efficient deorbit solution for future missions. Copyright © 2007 by Cranfield University.