Stratolaunch Systems Corporation is an American space transportation venture developing a new air launch to orbit system, with its corporate headquarters located in Seattle, Washington. The project was officially announced in December 2011 by Microsoft co-founder Paul G. Allen and Scaled Composites founder Burt Rutan, who had previously collaborated on the creation of SpaceShipOne.
The project is a mobile launch system with three primary components; a carrier aircraft being built by Scaled Composites (called the Stratolaunch), a multi-stage payload "launch vehicle" which would be launched at high altitude into space from under the carrier aircraft, plus a mating and integration system by Dynetics.
As of 2017, the first test flights were planned to begin in 2019, with a goal of a commercial launch by 2020.