Guy Norris/LOS ANGELES
NASA expects to issue a request for proposals at the end of March for the design phase of the International Space Station emergency crew return vehicle (CRV) due to enter service in 2003.
The CRV is similar to the X-24A lifting body, but would glide autonomously from orbit and use a steerable, parafoil parachute for its final descent. The CRV concept is being evaluated on the X-38 prototype, the first of which completed a flight on 6 February to verify improvements to the drogue and parafoil system at NASA's Dryden site at Edwards AFB, California.
The first free-flight of the second vehicle, number 132, is scheduled for the second week of March and will represent the initial flight of the full flight control system. The system, which uses electromechanical actuators throughout, will control the X-38 in free flight for about 17s on the first drop test. This time period will be extended progressively to more than 1min over successive tests planned between August and October.
The last sortie is expected to include a drop from the Boeing B-52 mother ship at 42,000ft (12,800m), allowing the craft to intercept the space flight entry trajectory from 40,000ft down.
The second X-38 incorporates a new rudder section following the failure of the first unit at altitude during the initial captive carry test when the build-up of internal pressure led to delamination and failure. "The good news was the actuators worked fine," says X-38 project manager John Muratore.
The space test vehicle, Number 201, is more than 60% complete at NASA's Johnson Space Center. The vehicle is full scale at 10m in length, as opposed to earlier scale models, and is deeper in profile to provide more capacity. In 2001, number 201 will be carried into space aboard the Shuttle Columbia.
NASA says the final cost for the four planned CRVs, plus a ground trainer and the X-vehicles, will be no more than $600 million.
Source: Flight International
