SCIENTIFIC AND TECHNICAL AEROSPACE REPORTS

A Biweekly Publication of the National Aeronautics and Space Administration
VOLUME 44, ISSUE 1 - January 13, 2006

15 LAUNCH VEHICLES AND LAUNCH OPERATIONS Includes all classes of launch vehicles, launch/space vehicle systems, and boosters; and launch operations.

For related information see also 18 Spacecraft Design, Testing and Performance; and 20 Spacecraft Propulsion and Power.

20060001781 Air Force Inst. of Tech., Wright-Patterson AFB, OH USA

Investigation of the Performance Characteristics of Re-Entry Vehicles

Bilbey, Charles A.; Sep. 1, 2005; 85 pp.; In English; Original contains color illustrations Report No.(s): AD-A440191; AFIT/GSS/ENY/05-S01; No Copyright; Avail.: Defense Technical Information Center (DTIC)

When a non-US spacecraft reenters the Earth's atmosphere, having the ability to accurately determine its performance characteristics is a primary concern. This study investigated the atmospheric re-entry profiles of a maneuverable re-entry vehicle. The re-entry vehicle was modeled as a point mass with aerodynamic properties. Equations of motion were numerically integrated, giving the time histories of position, velocity and flight path angle. The algorithm is able to generate a complete and feasible entry trajectory of a approximately 25-minute flight time in about 5 to 10 seconds on a desktop computer, given the entry conditions and values of constraint parameters. This preliminary study shows the feasibility of identifying and further exploring the technical challenges involved in using a mathemathical model to simulate the performance characteristics of the maneuvering re-entry vehicle. DTIC

Maneuverable Reentry Bodies; Reentry Vehicles

20060001809 Air Force Inst. of Tech., Wright-Patterson AFB, OH USA

The Effect of Aerodynamic Surfaces Versus Thrust Maneuvers on Reentry Vehicles

Albrecht, Meredith M.; Sep. 1, 2005; 85 pp.; In English; Original contains color illustrations Report No.(s): AD-A440289; AFIT/GAE/ENY/05-S01; No Copyright; Avail.: Defense Technical Information Center (DTIC)

This research effort analyzes the effect of aerodynamic surfaces versus thrust maneuvers on a reentry vehicle. At high altitudes the effect of aerodynamic surfaces on the reentry vehicle is small due to low atmospheric density; however as the vehicle reaches lower altitudes a lift maneuver is very successful in deflecting the vehicle and creating a large impact footprint. When a continuous thrust maneuver is input in the place of a lift maneuver the results are very similar at the highest maneuver altitudes, although the impact footprint shrinks rapidly as the maneuver altitude decreases. Additionally, when the thrust maneuver is along or opposite the velocity vector of the vehicle it significantly alters the time of flight, especially when performed at higher altitudes. In order to perform this analysis, a FORTRAN program using the equations of motion for a reentry vehicle was modified in order to accommodate the lift and thrust maneuvers. DTIC

Aerodynamics; Control Surfaces; Maneuverable Reentry Bodies; Reentry Vehicles

Source: NASA.