Stratolaunch to use Orbital ATK’s Pegasus rocket

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The competition heats up? Vulcan Aerospace and Orbital ATK announced today that they are renewing their partnership, using Pegasus in conjunction with Stratolaunch to put satellites into orbit.

Under a multiyear “production-based partnership,” the companies said, Orbital ATK will provide “multiple” Pegasus XL air-launch rockets to be used with the Stratolaunch aircraft, which, when completed, will have the largest wingspan of any plane ever built.

With the Pegasus XL rockets, the Stratolaunch aircraft will be able to launch small satellites weighing up to 1,000 pounds, according to the firms’ joint statement released Thursday. Pegasus rockets already have done this kind of work: Orbital ATK has used them to launch satellites from the belly of its Stargazer aircraft.

This deal suggests to me that Vulcan Aerospace has a problem. It couldn’t find anyone to build a large rocket for Stratolaunch and this deal was therefore conjured up to paper over this problem. First , it appears that the reason Orbital ATK originally backed out was that they didn’t want to build the new rocket. Maybe they had engineering concerns. Maybe they were worried about cost or management. Regardless, they didn’t want to build it.

Second, using Stratolaunch with Pegasus seems pointless if the satellite weigh is still limited to only 1,000 pounds. That’s the payload capacity of Pegasus using Orbital ATK’s L-1011 Stargazer airplane. Why bother switching to Stratolaunch if the giant plane doesn’t give you any benefits?

Thus, it appears to me that what has happened is that Vulcan needed some rocket to use with Stratolaunch so that they could squelch the rising doubts about the company. This deal gives them that. It also probably gives Orbital ATK some extra cash to get them to agree to do it.



  • Localfluff

    Pegasus is the most expensive launcher per kilogram to orbit. (You know, until SLS anyway). Small launchers and launches from aircrafts, are both problematic. Many have tried but few ever lifted anything. It’s easier to start up, but harder to make work. The space industry is a great mixture of geniality and madness. It’s sometimes hard to tell the difference. It’s a good thing that everyone interested is trying. Exploration requires ignorance, or else there would be nothing to explore, and sometimes madness is proven right.

  • Dave Williams

    What is the difference in maximum altitude that can be reached by Strato-launcher and Stargazer?

  • Dave Williams: I wondered also if Stratolaunch might have the ability to reach a higher altitude (and thus be able to launch larger payloads), but the article clearly states that the launch payload for Stratolaunch will be no greater than that of Starliner. So, even if Stratolaunch can fly higher, it doesn’t seem to matter.

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