The Stratospheric Observatory for Infrared Astronomy 747SP aircraft is currently flying the second segment of flight tests to prepare the observatory for Early Science missions. When completed, the SOFIA program will operate a fully capable observatory cleared for telescope cavity, door-open science instrument flights up to 45,000 feet.
Early Science is divided into two milestone events, Short Science and Basic Science. Short Science requirements involve clearing the SOFIA system for telescope assembly operations at or above 35,000 feet and with the telescope assembly and aperture operated at up to 40 degrees elevation. The second phase, Basic Science, requires the observatory to fly above 41,000 feet with the telescope assembly and aperture operating in its full range of 23 to 58 degrees elevation, which is the full range of vertical movement.
The nine flights planned for June through August include evaluation of the performance, handling qualities and structural characteristics of the aircraft. Test data will be collected to quantify airframe and telescope cavity acoustic and vibration characteristics. Results of testing during these and subsequent flights will meet airworthiness requirements for the 747 flying observatory and its 20-year operational lifetime.