ORBITALSCIENCES IS to produce four modified Pegasus air-launched boosters for NASA's Hyper-X hypersonic test programme.

The Hyper-X is a small, unmanned, research vehicle powered by a supersonic-combustion ramjet (scramjet) and designed to reach speeds of up to Mach 10 and altitudes of up to 100,000ft (30,500m) after launch from NASA's Boeing B-52.

Orbital's Hyper-X launch vehicle is based on the first stage of its Pegasus air-launched satellite booster. The Hyper-X will replace the second and third stages of the Pegasus and, after air-launch from the B-52 off the California coast, will be accelerated to the hypersonic speeds necessary for scramjet operation before separating from the booster. Orbital will modify the Pegasus thermal-protection system to cope with the "severe aerodynamic heating loads" associated with hypersonic flight.

Dulles, Virginia-based Orbital says that its contract covers the launch of four Hyper-X flights, one a year from 1998 to 2001.

Source: Flight International