Stratolaunch plane
Stratolaunch Systems’ twin-fuselage jet is shown under construction inside a hangar in Mojave, Calif. Vulcan Aerospace released the photo in April. (Credit: Vulcan Aerospace)

The world’s largest airplane is taking shape for Microsoft co-founder Paul Allen’s Vulcan Aerospace venture, but it’s not yet clear what kind of rocket would be launched from the Stratolaunch super-jumbo jet.

The uncertainties reflect transitions taking place at Vulcan Aerospace as well as in the launch industry. Last month, the venture’s president, Chuck Beames, said he was still in the midst of defining where Stratolaunch fit in the context of Vulcan’s wider “NextSpace” vision. Meanwhile, there’s been a switch in the CEO spot for the Stratolaunch Systems subsidiary, from Gary Wentz to Jean Floyd.

The past few months also have been marked by rapid shifts in the satellite launch industry – particularly for small to medium-size satellites, which are supposed to be in the sweet spot for Stratolaunch’s air-launch system. The Wall Street Journal quotes unnamed aerospace industry officials as saying those shifts could threaten the project’s overall viability.

In a statement emailed to GeekWire today, Vulcan Aerospace said the Journal’s report was “inaccurate” and “based on nothing more than rumors and speculation, not facts.” The statement went on to sketch out Vulcan’s vision of transforming space transportation to low Earth orbit by changing the current model for launching payloads into space:

“Today, space launch continues to be hampered by long delays and high costs, especially for the burgeoning class of space entrepreneurs.  To best serve the variety of space operators with more convenient and less expensive options, we envision affording the satellite operator multiple launch vehicle options with varying payload capabilities. An effort of this scope and ambition is a massive undertaking and takes time to develop. We are unwavering in our commitment to its success and expect to achieve additional milestones in 2016, as we continue to advance against our original timeline of being fully in service by the end of the decade.”

Stratolaunch is being built for Vulcan inside a hangar in Mojave, Calif., by Mojave-based Scaled Composites – a Northrop Grumman subsidiary that created the history-making SpaceShipOne rocket plane with Allen’s backing more than a decade ago. The twin-fuselage, six-engine Stratolaunch jet will boast a record-setting 385-foot wingspan. It’s designed to launch rockets into orbit from high altitudes anywhere in the world.

The latest word on Stratolaunch’s progress came back in April, when Beames reported that 80 percent of the airplane’s parts had been fabricated and that construction was 40 percent complete. Vulcan’s most recently announced timeline calls for the giant jet to be completed and go into testing next year. That schedule, however, is dependent on how the project copes with technical challenges as well as shifting markets and partnerships.

An air-launch system similar to Stratolaunch’s, albeit on a much smaller scale, has been used by Orbital ATK for its Pegasus rocket. Orbital was at one time a partner in the Stratolaunch project – but in June, Beames said Vulcan Aerospace was rethinking its rocket plans because of the rapid rise in capability for small satellites, including CubeSats.

This summer, Beames said Vulcan Aerospace would make announcements about its future partnerships in the fall. If the company decides to hook up with Orbital again, a new deal would have to be forged.

Nearly four years after Allen unveiled the Stratolaunch project, the small-satellite launch market has become much more competitive: OneWeb has made progress on a plan to send up more than 600 satellites to create a global constellation for low-cost Internet access. Seattle-based Spaceflight, meanwhile, is pioneering a “dedicated rideshare” system that bundles small satellites to go onto big rockets such as the SpaceX Falcon 9.

Questions over the future of the small-satellite market add to the uncertainty. Even SpaceX, which was a Stratolaunch rocket partner before Orbital entered the picture, is rethinking plans to put up its own Internet satellite constellation due to market considerations.

The Stratolaunch concept could still have an advantage over fixed launch sites, in that payloads could theoretically be put into orbit anytime from anywhere. That kind of capability could be particularly attractive for the U.S. military, which is studying multiple avenues for routine, reliable access to space.

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