Design and Operation of the NASA 915-cm Airborne Telescope

Abstract

A 91.5-cm aperture telescope is being built for ir and submillimeter observations at altitudes of 12 km to 14 km aboard a StarLifter (Lockheed C-141A) aircraft. The main optics will be totally reflecting, and aerodynamic boundary layer control will permit open-port operation (no material window). The elevation will be adjustable in flight between 35° and 75°. Westward flying will permit several hours’ observation of an object near transit at constant bearing (azimuth) and with little change in elevation. An air bearing support with inertial stabilization and star tracking will give a net line-of-sight stability of better than 2-sec of arc rms in the open-port mode.