The Space Reviewin association with SpaceNews

NASA could test advanced technologies like the VASIMR engine, shown here sending a mission to Mars, by having it adjust the orbit of the International Space Station. (credit: NASA)

The Vision for Space Exploration needs transformational technology

Many space enthusiasts write and speak about space tourism as the great force that will start rapidly propelling the human race into being a space faring species to stay. I for one do not buy the notion as the near term panacea yet. Just as many sports prognosticators are proven wrong I may be as well, but in this case I don’t think so.

The most recent issue of Popular Science has an article about Bigelow Aerospace and Robert Bigelow’s dream of building a space hotel. His firm has taken over the inflatable structure technology that was started by NASA. I have no argument with the technology that Bigelow is working on. It is based on sound principles of physics and is truly innovative and transformational. I have a problem, however, with the realism in the ideas for getting tourists to and from his proposed orbital hotel.

In the Popular Science article there is a short section about SpaceDev proposing a five-passenger craft based on NASA’s X-34 research vehicle. The article suggests that using the design would simplify the development of a manned vehicle because the aerodynamics have been worked out. The implication from this article and many others I have read are that these ideas can be scaled up into reliable low-cost orbital vehicles without spending the billions of dollars firms like Boeing and Lockheed Martin do on government contracts. The impression is that if venture capitalists would just give them a few hundred million and the government would just get out of the way, they would quickly have cheap orbital vacations for the masses. Physics and other realities get in the way.

SpaceShipOne and the White Knight carrier aircraft are extremely impressive accomplishments that use the best of both well-proven and newer transformational technology.

As impressive as Scaled Composites’ suborbital hops are, the difference between what they did and developing a safe, reliable orbital vehicle is neither trivial nor inexpensive. It is true that any large corporations like Boeing and Lockheed have expensive overhead and inefficiencies in place that add to the cost of vehicle development. They also, though, have significant resources and capabilities to help ensure the success of a large project. These resources are absolutely vital to the development of a launch vehicle.

SpaceShipOne and the White Knight carrier aircraft are extremely impressive accomplishments that use the best of both well-proven and newer transformational technology. Using a carrier aircraft to launch a rocket ship is a decades-old concept that was used on the X-15 project. Building it out of advanced composites like the new Boeing 787 Dreamliner to cut weight and size and increase lifting capacity and launch altitude is an example of utilizing truly transformational technology. The use of a hybrid rubber-nitrous oxide rocket engine to cut costs and radically reduce the dangers normally associated with rocket fuel is another transformational technology. The accomplishment of Scaled Composites when considering their budget is also incredible.

Extending the technology developed with SpaceShipOne to slightly larger vehicles to carry a half-dozen passengers on regular treks into orbit with the budget that will be available with Richard Branson’s investment seems very reasonable and realistic. Only time will tell if suborbital tourist hops will become a successful business. Extending that to orbital flights is where the reality of physics, engineering, and finance become a real problem.

People in the space enthusiast community tend to forget about some of the real challenges that come when you try to extend technology like SpaceShipOne and the X-34 into manned vehicles capable of reaching orbit. The first problem is the energy required getting into orbit. While SpaceShipOne uses an innovative hybrid rocket engine, it can only reach about one-sixth the velocity to reach orbit. Using rockets to reach orbit requires a significant portion of its mass to be fuel and oxidizer. It also requires an energy density greater than rubber and nitrous oxide can provide, leaving usually expensive and much less safe cryogenic choices. The mass that reaches orbit must also have many things that SpaceShipOne does not have. This includes thermal control systems, large onboard power systems if the missions are to last more than a few hours, heavy life support systems, highly capable communications and tracking equipment, food, water, waste disposal, and more. As any engineer worth his salt will tell you, integrating and testing a much more complex system adds immensely to the cost. All of this also ignores the massive infrastructure needed to launch, track, and communicate with these vessels.

If space travel is to ever become much more commonplace, it will need transformational technology. The information that has become available on President Bush’s vision for returning to the Moon and beyond seems to consist of modern versions of very old proven concepts.

The second part of the notion is that venture capitalists will put up the money necessary to create privately-funded access to orbital space stretches the imagination. Unless someone with Bill Gates’ resources is willing to put up a significant portion—if not most—of his wealth into such a project, the next most likely source of funds are venture capitalists. Having dealt with venture capitalists while looking for funding for my business I have developed an insight as to what makes them tick. Selling them on any concept, much less this one, is not an easy task. Venture capitalists are looking for the “home run” high-return moneymakers like Google. They also are not too interested in waiting ten or more years to get their return.

If space travel is to ever become much more commonplace, it will need transformational technology. The information that has become available on President Bush’s vision for returning to the Moon and beyond seems to consist of modern versions of very old proven concepts. This vision needs to make room for transformational technology. It needs to be flexible to make room for both small-scale and large-scale transformational technologies. It needs to make room for using ideas from both large firms like Boeing and Lockheed Martin and small, highly innovative firms like Scaled Composites, Bigelow Aerospace, and SpaceDev.

If humanity is to return to the Moon and on to Mars and other locations, we need to make better user of existing ideas and resources. When the shuttle is retired and the launch pad for Soyuz flights is operational in French Guiana, the International Space Station needs to be shifted to an orbit more conducive to launches from Florida or near the equator. Doing so would make it much more useful as a staging point for missions beyond low Earth orbit. Placing a Variable Specific Impulse Magnetoplasma Rocket (VASIMR) engine on the ISS would be an ideal long-term test of high specific impulse propulsion for eventual use on deep space missions. It may take several years to change the orbit, but each degree reduction in inclination along the way would radically increase the payload any launch vehicles from Florida or French Guiana could carry to it.

If developing an air-breathing launch vehicle using scramjet technology could bring the cost of a manned flight to orbit down even one order of magnitude while increasing the reliability and frequency of flights, it should be done. Last year’s successful Mach 10 hypersonic flight of the X-43A proved the concept. Air-breathing hypersonic launch is far too valuable to let disappear into some secret weapons program in the Pentagon.

The Lockheed Martin-led team developing concepts for the Crew Exploration Vehicle includes the European firms EADS. I suspect that they are doing this because they think that the European Space Agency is going to be invited to take part in and help fund the vision NASA is embarking on. Europe’s Aurora program needs that kind of kick to turn it into a serious program. Inviting the Europeans in will also have benefits in strengthening transatlantic ties, and will also make it harder for future Congresses or administrations to kill or derail the vision.

I look forward to the next great idea from Burt Rutan and the other innovative thinkers out there. They need to be involved when NASA, ESA, and other organizations take the next steps. If not on the teams competing for contracts, their ideas and the ideas of others should be looked at for finding the truly workable innovative ideas to improve the proposals that will come from Boeing and Lockheed. I have my ideas as to where everything will be going. If enough of us have ideas and push them forward, one of us is bound to be right. Let the journey begin.