The Stratolaunch system has entered system design review (SDR), says team partner Dynetics, a key milestone in designing the unique and complex launch vehicle.

After completing SDR, design will continue until the preliminary design review (PDR) in the fall, and the critical design review (CDR) in mid-2013. After CDR, the aircraft's design will be finalized and hardware construction will begin.

Construction of the Mojave, California hangar, in which the aircraft will be assembled, is progressing rapidly. "The steel is coming out in various partsyou cannot miss it, and when the hangar goes up you won't miss it," says Dynetics chief technologist Steve Cook. "Interestingly enough, the critical path is heavily dependent on that hangar getting built."

Scaled Composites, which is building the aircraft, has purchased two ex-United Boeing 747-400s, and is in the process of dismantling them. Stratolaunch will use the engines, hydraulics system and several other major components to build its own aircraft. The remaining fuselage and wing shells will be scrapped.

SpaceX is building the rocket, which will launch approximately 13,000lb into orbit. "This is really going after the Delta II market," says Steve Cook, Dynetics chief technologist. The group eventually hopes to qualify the system for human spaceflight and begin launched manned spacecraft.

Source: Flight International