A preliminary investigation was conducted to determine the navigational accuracy required by the Aeromaneuvering Orbit-to-Orbit Shuttle (AMOOS) during the atmospheric phase of flight. The guidance scheme, which is the same as the one developed by Lockheed in the original AMOOS study, uses the parameters of velocity, flight path angle, and density altitude to correct to a nominal trajectory. Density altitude is obtained from atmospheric density, which is calculated from vehicle acceleration. Errors in velocity, flight path angle, and acceleration were introduced into a three-degree of freedom computer simulation of the vehicle trajectory using bank angle commands generated by the guidance equations. Deviations from standard atmospheric density were taken into account. The maximum errors allowable that still permitted the vehicle to attain its phasing orbit apogee altitude of 720 km (+ or - 100 km) were determined. Three types of error were investigated: constant, sinusoidal, and random. For time-varying errors the frequency dependence was examined, as was cross-coupling of errors. It was concluded that the guidance scheme can tolerate fairly large errors and still guide to an acceptable apogee altitude. The navigational accuracy required for the atmospheric phase of flight is within the capability of present day astrionics. (Author)
Navigational Accuracy Requirements of Aeromaneuvering Space Vehicles
1977
73 pages
Report
Keine Angabe
Englisch
Manned Spacecraft , Spacecraft Trajectories & Flight Mechanics , Astronautics , Navigation , Aerospace craft , Hypersonic vehicles , Space shuttles , Lifting bodies , Maneuvering satellites , Accuracy , Banking , Turning flight , Angle of attack , Earth orbits , Theses , AMOOS(Aeromaneuvering Orbit to Orbit Shuttle) , Aeromaneuvering orbit to orbit shuttle