Microsoft co-founder Paul Allen this week announced his first new space venture since winning the Ansari X-Prize in 2004. Stratolaunch brings together Allen, his X-Prize partner Burt Rutan of Scaled Composites, and Elon Musk’s SpaceX corporation located in Hawthorne CA. Musk is also known as the founder of Paypal and Tesla Motors. Stratolaunch’s headquarters will be in Huntsville Alabama, also known as ‘Rocket City’.
You may recall the Spaceship One program used a carrier plane called the White Knight to lift the rocket powered space plane to about 50 thousand feet altitude. Although Spaceship One ‘reached space’ in order to win the ten million dollar prize, it did not and could not reach orbit. Scaled Composites is currently scaling up the design to supply Spaceship Two and White Knight Two for Richard Branson’s Virgin Galactic. However like Spaceship One, Virgin Galactic’s service will be suborbital, which makes the ‘Galactic’ part of the title seems a bit exaggerated.
There is a huge difference between making it into space and making it into orbit. Huge is also the only word to use when describing Stratolaunch’s plans. The carrier aircraft will have a wingspan of 385 feet, which will make it, by a substantial margin, the largest aircraft ever built. The current record holder – Hughes H4 Hercules (aka the “Spruce Goose”) – has a wingspan just under 320 feet. The White Knight Two has a wingspan of 141 feet, and is the largest craft built so far by Scaled Composites. The Stratolaunch craft, like Spaceship Two, will have two fuselages with the spacecraft hung on the wing beneath. It will be powered by six engines of the type found on the 747. The total weight of the Stratolaunch craft at takeoff will be 1.2 million pounds, of which 490 thousand pounds will be the rocket hung underneath the middle wing. The two-stage rocket will be a scaled down version of SpaceX’s current Falcon 9, which weighs in at 735 thousand pounds. Total payload to low Earth orbit will be 13,500 pounds. That is smaller than many other launch systems, including the standard Falcon 9 at 20 thousand pounds.
Stratolaunch hopes to win over competing launch companies based on frequency and flexibility. Or as they term it in the promotional video, “Any Orbit, Any Time”. This is because the carrier aircraft can fly to wherever is the right location for the launch, rather than have to wait for the right location to arrive at the launch site. Since the carrier is a conventional aircraft, the turn around time should be fairly brief. Stratolaunch is not yet promising daily launchings, but it is not out of the question. It is likely that the limiting factor will be SpaceX’s manufacturing speed of the modified Falcon 9 rockets. Next year, SpaceX plans to be able to produce as many as one of the current Falcon 9 every six weeks. During the downtime, the Stratolaunch carrier could fill in with assignments as the world’s heaviest-lifting cargo plane.
As for the Southern California angle, SpaceX’s headquarters is in Hawthore, But more importantly, Stratolaunch announced that it signed a long term lease for 20 acres at Mojave Airport to build the huge hangar where the carrier will be built and serviced. It was not announced where SpaceX will build the rockets or prepare them for launch, but it will need to be a facility with a runway of at least 12 thousand feet long, and enough clear width to accommodate the carrier’s Wingspan. Mojave’s dry and predictably sunny climate wouldn’t hurt either. If SpaceX decides to co-locate the final rocket assembly and preparation functions for Stratolaunch with the carrier maintenance at Mojave, it would be a double boost to the local aerospace industry.
Here is Stratolaunch’s promotional video of their planned launch system.