Lifting Reentry Vehicle Research Articles

Optimal control of a reentry vehicle in the presence of measurement uncertainties

Trajectory control of a lifting reentry vehicle is considered. Control of the vehicle flight path is obtained by rolling the vehicle about the relative wind axis, thereby altering the direction of lift. A method is developed for determining the controller which minimizes the expected total number of roll maneuvers, plus a quadratic penalty imposed on the miss distance at the target. A numerical example is presented and the physical significance of the solution is explained.

Re-entry filtering, prediction, and smoothing.

Covers advancements in spacecraft and tactical and strategic missile systems, including subsystem design and application, mission design and analysis, materials and structures, developments in space sciences, space processing and manufacturing, space operations, and applications of space technologies to other fields.

Elastomeric thermal shield systems for lifting reentry vehicles.

The capability of elastomeric ablative thermal shield materials to meet the system requirements for lifting re-entry vehicles having lift-to-drag ratios of 0.5 to 1.5 when entering the earth's atmosphere from near earth orbits is investigated. Chemically blown phenyl-methyl silicone elastomeric foams are examined and compared with a representative elastomeric syntactic foam. The thermo-mechanical compatibility, high-temperature stability, environmental resistance of the chemically-blown elastomeric foam ablative, and its resistance to ablation and degradation at the relatively low-heat-flux, long-time heating conditions of lifting re-entry vehicles, are presented. Equilibrium glide trajectories, heating environments, and shear forces are shown for representative re-entry conditions. Ablation-insulation material weights are calculated from experimental data. A structural weight tradeoff is made for aluminum and titanium sheet-stringer construction. The extreme low temperature capability and compatibility of the chemically-blown phenyl methyl silicone elastomeric foam with metal structures are examined for temperatures of — 290°F. Fabrication and attachment methods are discussed.

Some fundamental considerations for lifting vehicles in return from satellite orbit

Basic performance areas, including orbit ejection, re-entry and landing, associated with return from near-Earth orbits utilizing unpowered lifting re-entry vehicles are examined in order to establish preliminary design criteria. Aerodynamic heating and maneuvering aspects are considered. Skip and glide paths are compared. A composite path to best perform re-entry is postulated.