Assured crew return vehicle

Claim 1

A method for safely and economically returning a human crew to earth from an earth orbiting craft, using a return vehicle attached to the orbiting craft and specially adapted for such use, comprising the steps; a) entering the return vehicle from the orbiting craft; b) starting individual crew breathing air supply; c) activating automatic controls of the return vehicle; d) initializing an inertial measuring unit aboard the return vehicle using state vector and attitude data obtained from the orbiting craft; e) releasing the return vehicle from the orbiting craft; f) updating periodically return vehicle state vectors and attitude using only onboard data; g) initiating automatically a reaction control system to maneuver the return vehicle away from the orbiting craft to preclude recontact between the return vehicle and the orbiting craft; h) entering crew weight into return vehicle computer; i) selecting manually one of a number of predetermined landing sites on the surface of the earth as a landing target; j) establishing automatically a return vehicle pre- burn attitude; k) calculating automatically a deorbit burn initiation time; l) firing automatically a deorbit thruster; m) maintaining automatically the proper return vehicle attitude throughout deorbit burn; n) terminating deorbit burn after elapse of appropriate time interval to effect desired ballistic trajectory for placing the return vehicle on the surface of the earth near the selected landing site; o) jettisoning the deorbit thruster; p) maneuvering the return vehicle automatically to ensure return vehicle trajectory and deorbit thruster trajectory do not intersect; q) establishing and maintaining automatically return vehicle entry attitude; r) initiating return vehicle roll rate; and s) deploying parachutes for decelerating return vehicle to acceptable impact velocity.

Claim 2

A method for safely and economically returning a human crew to earth from an earth orbiting craft, using a return vehicle attached to the orbiting craft and specially adapted for such use, comprising the steps; a) entering the return vehicle from the orbiting craft; b) starting individual crew breathing air supply; c) activating automatic controls of the return vehicle; d) initializing an inertial measuring unit aboard the return vehicle using state vector and attitude data obtained from the orbiting craft; e) releasing the return vehicle from the orbiting craft; f) updating periodically return vehicle state vectors and attitude using only onboard data; g) initiating automatically a reaction control system to maneuver the return vehicle away from the orbiting craft to preclude recontact between the return vehicle and the orbiting craft; h) entering crew weight into return vehicle computer; i) selecting manually one of a number of predetermined landing sites on the surface of the earth as a landing target; j) establishing automatically a return vehicle pre- burn attitude; k) calculating automatically a deorbit burn initiation time; l) firing automatically a deorbit thruster; m) maintaining automatically the proper return vehicle attitude throughout deorbit burn; n) terminating deorbit burn after elapse of appropriate time interval to effect desired ballistic trajectory for placing the return vehicle on the surface of the earth near the selected landing site; o) jettisoning the deorbit thruster; p) maneuvering the return vehicle automatically to ensure return vehicle trajectory and deorbit thruster trajectory do not intersect; q) establishing and maintaining automatically return vehicle entry attitude; r) initiating return vehicle roll rate; and s) deploying parachutes for decelerating return vehicle to acceptable impact velocity.

Claim 7

The method of effecting crew or cargo return to earth from earth orbit comprising the steps a) maintaining at an orbital location a return vehicle; b) providing to the return vehicle state vectors from an attached orbiting spacecraft; c) detaching the return vehicle from the orbiting spacecraft; d) calculating from the state vectors of the return vehicle one or more acceptable landing sites; e) selecting the desired landing site; f) automatically orienting the return vehicle attitude for a deorbit burn; g) initiating deorbit burn h) maintaining vehicle attitude during burn i) continuing deorbit burn for length of time sufficient to effect minimum distance from projected landing site to selected landing site; j) monitoring reentry parameters by periodically comparing with preselected limits; k) terminating deorbit burn prior to effecting minimum distance of step i) when necessary to keep reentry parameters within preselected limits.

Claim 8

The method of effecting crew or cargo return to earth from earth orbit comprising the steps a) maintaining at an orbital location a return vehicle; b) providing to the return vehicle state vectors from an attached orbiting spacecraft; c) detaching the return vehicle from the orbiting spacecraft; d) calculating from the state vectors of the return vehicle one or more acceptable landing sites; e) selecting the desired landing site; f) automatically orienting the return vehicle attitude for a deorbit burn; g) initiating deorbit burn h) maintaining vehicle attitude during burn i) continuing deorbit burn for length of time sufficient to effect minimum distance from projected landing site to selected landing site; j) monitoring reentry parameters by periodically comparing with preselected limits; k) terminating deorbit burn prior to effecting minimum distance of step i) when necessary to keep reentry parameters within preselected limits.