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As it continues development of its Lynx spaceplane, XCOR Aerospace, like many other suborbital vehicle developers, has been courting business from the emerging research market. (credit: XCOR Aerospace)

Suborbital back out of the shadows

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For much of the previous decade, commercial human spaceflight was most closely associated with suborbital spaceflight. That linkage first became prominent in April 2003, when Scaled Composites unveiled SpaceShipOne, its entry into the Ansari X PRIZE competition (see “Rutan aims for space: A look at SpaceShipOne”, The Space Review, April 21, 2003). While the competition had been going on since the mid-1990s, Scaled’s rollout, and the company’s track record in building and flying innovative aircraft while many other X PRIZE entrants had not made it past the PowerPoint stage, demonstrated that this field was real. And, 18 months after that rollout, SpaceShipOne claimed the $10-million prize by flying to space twice within a week, capturing the attention of the industry and the general public.

In recent years suborbital spaceflight has lost some of its luster.

For several years after those historic flights, suborbital spaceflight was seen as the future for commercial human spaceflight, at least for the foreseeable future. Several companies put their energies into developing vehicles, including Virgin Galactic, which partnered with Scaled to develop SpaceShipTwo. New Mexico invested $200 million of state and local tax money to build a commercial spaceport named Spaceport America for use by Virgin and others, while other states sought to make use of existing spaceports or airports to serve this market. Soon, industry advocates stated, suborbital vehicles would be taking off from those spaceports, giving thousands of people a year the experience of spaceflight.

However, in recent years suborbital spaceflight has lost some of its luster. Part of it has to do with the delays in developing the vehicles, as companies suffered from technical problems and/or financial issues. Virgin Galactic, for example, said back in 2004, when they announced their plans to work with Scaled, that they expected to enter commercial service as early as late 2007. As of early 2011, they had not done so. Some ventures, like Rocketplane, went out of business. The economic crisis of the last several years has made it difficult for companies to raise money, while in New Mexico the new governor has said she will not support any future state investment in Spaceport America as she seeks to cut state spending.

Meanwhile, commercial orbital human spaceflight has attracted considerable interest—and money—in the last few years, driven by NASA’s needs to access the International Space Station once the shuttle is retired and the agency’s new preference to rely on commercial providers to meet that requirement. A mix of entrepreneurial and established aerospace companies, from SpaceX to Boeing, have dived into this market, developing concepts for spacecraft and launch vehicles to meet NASA’s needs as well as those for other commercial customers, from space tourists to the national space agencies Bigelow Aerospace has been courting as “sovereign clients” for its planned commercial space stations. Suborbital has effectively been overshadowed by the attention orbital human spaceflight has been getting.

However, the suborbital industry may be ready to step up and out of the shadow cast by orbital ventures. Several companies have been making steady—if slow—progress on vehicle developments. And, as evidenced by a conference on suborbital research convening this week in Orlando, suborbital has found market niches beyond space tourism that demonstrate its potential for significant growth in the years to come once those vehicles start flying.

A suborbital vehicle progress report

At the 14th Annual FAA Commercial Space Transportation Conference in Washington earlier this month, representatives of four companies actively developing suborbital vehicles—Armadillo Aerospace, Masten Space Systems, Virgin Galactic, and XCOR Aerospace—discussed their ongoing efforts. While not a complete census of the industry (a notable omission was publicity-shy Blue Origin) the panel did offer a broad review of the state of the industry’s development and their issues they’re facing.

“We’re making progress,” said George Whitesides, CEO and president of Virgin Galactic. “Space is always exciting but hard, and I think everyone who’s building hardware here knows that.”

“It uses all of our existing technologies—we didn’t have to invent anything new for this vehicle—and it’s got phenomenal capabilities,” Milburn said of Armadillo’s “Tube” rocket.

Virgin is currently performing glide tests of SpaceShipTwo, with four completed as of this month. (At the conference Whitesides said a fifth glide test would be coming soon; according to Scaled’s flight logs, a glide test was planned for February 15 but aborted because of “deteriorating weather”.) As is traditional for the company, Whitesides didn’t give specific dates on when they expected to put SpaceShipTwo into commercial service, or even when powered test flights would begin. However, in an interview earlier this month with the Indian magazine Businessworld, Virgin’s Stephen Attenborough said that they planned to carry out five to six glide flights, suggesting that this phase of the testing program is nearing its end; he added he was “hopeful” the first flight into space by SpaceShipTwo would be “this year or early next year.”

Just down the flight line from Scaled’s facility at the Mojave Air and Space Port in California, XCOR is continuing work on its Lynx spaceplane. This has included an “awful lot” of tests of the 5K18 engine, four of which will power the Lynx, XCOR president Jeff Greason said, adding that the last few technical milestones for the engine are largely complete. They have also been working on non-toxic reaction control system (RCS) thrusters, a project that Greason said was more challenging in some respects than the larger main engine, but critical to the company’s vision of rapid turnaround times that would not be possible if conventional hydrazine RCS systems are used. The Lynx design has been through two rounds of wind tunnel tests, with a final round planned for later this year for some final tweaks.

Masten Space Systems, also based in Mojave but focused on vertical takeoff and landing vehicles, has leveraged its success in the Northrop Grumman Lunar Lander Challenge (NGLLC) in 2009 (see “A wild finish for the Lunar Lander Challenge”, The Space Review, November 9, 2009) to continue its suborbital vehicle development. That current work has focused on a vehicle called Xaero, a reconfiguration of the Xoie vehicle that won first prize in Level Two of the NGLLC with some new systems as well as an aeroshell. “It’s not just PowerPoint; it exists,” said Masten’s Colin Ake, showing photos of the vehicle. Earlier this month Xaero made its first tethered flights, a prelude to free flights supported by NASA’s Commercial Reusable Suborbital Research (CRuSR) program. While Xaero can carry a 10-kilogram payload to an altitude of 30 kilometers, Masten is also working on a larger vehicle, dubbed Xogdor, capable of flying to 100 kilometers.

Texas-based Armadillo Aerospace, which as experimented with a variety of vehicle design concepts over the years, is shifting designs yet again, according to Neil Milburn, Armadillo’s vice president of program operations. Armadillo’s latest project is the descriptively-named “Tube” vehicle, a long, skinny rocket, which Milburn said has the unofficial nickname “Stig” after the character from the British racing show Top Gear. “It uses all of our existing technologies—we didn’t have to invent anything new for this vehicle—and it’s got phenomenal capabilities,” he said, adding that it could be clustered and staged for greater performance. The first flights of the vehicle are planned for as soon as March from Spaceport America.

In addition to the Tube rocket, Armadillo has been designing a suborbital crewed vehicle called the Suborbital Space Transport, or SOST, as part of its partnership with space tourism company Space Adventures announced last year (see “Rockets and rhetoric in Chicago”, The Space Review, June 1, 2010). Milburn described SOST as a “capsule sitting on top of a reusable booster section” designed to take off and land vertically, with the capsule able to separate from the booster in an emergency. Six meters tall and 2.5 meters in diameter, the vehicle could carry two people to 100 kilometers. “A boilerplate version will fly this year, period,” he said.

Research market evolves

While vehicle developers make steady, if slow, progress on their vehicles, one of the potentially major markets for these systems is showing more rapid growth. Prior to a few years ago, industry observers widely considered space tourism as the largest—and possibly only significant—market for commercial suborbital vehicles. However, researchers have increasingly become aware of the potential utility these vehicles could have in a wide range of research sectors, taking advantage of the relatively low-cost, if brief, access to microgravity and the space environment these vehicles offer.

“Because of the frequency of flight and the low cost, we’re going to see a real revolution in terms of what we can do by putting researchers and their payloads in space on a frequent basis,” Stern predicted.

“This has really come to be a second bull market” for suborbital vehicles, said Alan Stern of the Southwest Research Institute (SwRI) at the FAA conference. Stern has been perhaps the biggest advocate for what he calls the “research and education market” for suborbital vehicles. Last year he organized the first Next-Generation Suborbital Research Conference (NSRC) in Boulder, Colorado, with attendance far exceeding expectations (see “Suborbital research gets ready for liftoff”, The Space Review, March 1, 2010). The second NSRC starts today at the University of Central Florida in Orlando.

“Because of the frequency of flight and the low cost, we’re going to see a real revolution in terms of what we can do by putting researchers and their payloads in space on a frequent basis,” he predicted. “In four or five years we could have as much microgravity research time in suborbital vehicles as we have on the ISS,” albeit in increments of a few minutes at a time.

Stern’s institution is putting its money behind those claims. A year ago SwRI announced it would put $1 million of its own funding towards a suborbital researcher program to develop and fly a variety of experiments. Last week XCOR Aerospace announced it had sold six Lynx flights to SwRI for flights of researchers affiliated with the institute, performing biomedical, microgravity, and astronomy experiments. “XCOR and SwRI are blazing a pioneering trail with this engagement and setting the stage for others to follow with their experiments,” Stern said in the release. (And, as this article was being prepared for publication, Virgin Galactic announced that it had sold two SpaceShipTwo tickets to SwRI for research missons.)

Vehicle developers appear increasing cognizant of this market (particularly those, like Masten, that have no immediate plans for crewed flights and thus are more dependent on research customers) and are taking steps to serve them beyond just selling tickets. XCOR announced today that it’s created a global network of payload integrators to help sell research payloads that can fly on the Lynx. “This is a win-win for all of us,” said XCOR’s Greason in the statement announcing the partnerships. “XCOR will focus on what we do best, which is build and operate rocket powered vehicles, while our payload integration specialists will do what they do best, which is work closely with scientists and researchers and use their collective expertise to prepare payload missions to do real work in space.”

This combination of technical progress and increased customer interest has made some optimistic about the prospects of suborbital vehicles in the near future. “I’m pretty bullish about the suborbital market,” George Nield, associate administrator for commercial space transportation at the FAA, said at his conference earlier this month. The industry still faces many challenges ahead to build and fly suborbital vehicles and generate revenue with them, be it from tourists, researchers, or others. But if successful, the industry could soon be out of the shadows and streaking towards the skies.