The Rocket Company tells the story of the development of an RLV, mxing fiction with the fundamentals of launch vehicle design. (credit: Doug Birkholz)

The men of The Rocket Company (part 2)

by Mark Trulson
Monday, January 30, 2006

[Editor’s Note: Part 1 of this interview appeared last week.]

TSR: Every where you look it seems you have a new concept on what is needed to bring launch rates up and costs down. Ideas tossed around range from RLV, SSTO, TSTO, VTOVL, space elevators, and exotic propulsion systems. If you had to name two to three things, be it hardware or methods/systems we need to reduce the costs, what would you come up with?

TRC: Really, all the key pieces are there, or close: a really robust, reliable, and affordable thermal protection system will take some development work. But, there is nothing else that is lacking. The RL10, RL60, and various Russian engines are proof that we know how to build good reusable rocket engines. If you don’t try to build an SSTO, the necessary structures aren’t magic. The key is to look at what we do have in hand and put it together into a space transport that will provide some useful lift capability, with operations costs that are as low as you can make ’em. I’d say the two things would be to take the technology capabilities that exist and design a system with low operating costs as the driver.

Maybe the third thing is to realize that we need an operational orbital system, with almost any payload/crew/passenger capacity, that can be brought into service as inexpensively and quickly as possible. The sooner we get something flying, and flying frequently, the faster costs and prices will fall.

TSR: What are your thoughts about Rutan and Branson’s “The Spaceship Company”? Do you think suborbital flight is a necessary building block on the way to an orbital RLV?

TRC: Well, we like the name, certainly! More to the point, we like their announced strategy of selling SpaceShipTwos to anybody who wants to buy and operate them. In terms of suborbital systems as building blocks on the way to orbital vehicles, they don’t necessarily have to be, from a technology standpoint. But it may be a step that needs to be taken in order to get to the point where there is enough investor, public, and regulatory confidence in commercial rockets and the alt.space industry to invest the amount of money necessary to develop orbital systems. It will be interesting to see if indeed the various suborbital operators and builders can make enough money to sustain their companies and allow them to grow into viable businesses that eventually develop and market orbital vehicles. Maybe they’ll be short-term steppingstones, but that may be enough.

TSR: What other projects do you have in the works? Will we be seeing a sequel to this book or possibly another book covering a different topic?

TRC: We’ve discussed several other book ideas, but haven’t committed to anything yet. I guess we’re waiting to see how The Rocket Company does.

TSR: Are there any aspects of the book's premise that people have shown some doubt such as the small payload size of the launch or monasteries on the Moon? I realize that the monastery portion was used to show that once cheap access to space is available nothing would be off the board, but how do you respond to such comments?

TRC: Some people have said that 5,000 pounds [2,270 kilograms] of payload is too small, but we like to point out that many successful commercial aircraft carry less than that. We really need to start thinking of space transports in a new way, which is to say, like we think of terrestrial transports. Not as highly specialized vehicles that carry single, extremely expensive, relatively fragile spacecraft into orbit. We need space transports that you can use for “cargo”, not just “payloads.”

However, we generally get more resistance to the idea that tens or hundreds of such vehicles could be sold. People look at the existing miniscule scale of demand for space transportation and ask who would possibly be able to fill that many vehicles? Our answer is: “Nobody knows, and nobody will know until you have an opportunity to fill them.” Which is one reason we favor a smaller, more flexible vehicle over larger heavy-lift vehicles. We just don’t think that demand can be created out of nothing—we have to have a fleet of space transports in being in order to stimulate the development of new demand. A small space transport, affordable to own and operate, will enable that. And such a vehicle would, we think, be very attractive to many nations, institutions, companies, and even individuals around the world who want to be players in space. The aircraft companies built and sold a lot of airplanes in the early days before people were able to figure out how to make money with them.

TSR: You mentioned heat shields as one of the needed technologies that are at this point missing yet well within reach. Are you aware of any research going on in the areas needed to protect the engines and other systems in the reentry method you've outlined in the book?

Dave: Protecting the engines for a base-first reentry is a challenge, and I don’t know of any work being done in that area. For the rest of the vehicle, I have actually done some work for t/Space on transpirational cooling, which appears promising but that does require some additional development work. Beyond that, the current emphasis appears to be on improved blanket and tile systems.

Patrick: Very good blanket materials have been developed at NASA’s Ames Research Center. Early generations of these materials are used on the shuttle. The DH-1 basically takes the existing blanket materials and adds some compound like magnesium sulfate, which releases its water of hydration upon reentry heating, and rehydrates after sitting a moist atmosphere for a few hours or days. Cooling the engines is not that big a problem because the engine bay occupies less than 10% of the area of the base heat shield. Even brute force cooling with water has a weight penalty of only 100 pounds [45 kilograms] or so.

TSR: In your opinion, what are the most interesting things going on in the space arena today?

Dave: What’s really exciting is the number of new companies being well funded by wealthy, space-enthusiast individuals. Private money is essential to make a real revolution in space transportation happen, and the amount needed is significant. But justifying investments in this industry is still very iffy. These guys aren’t dependent on finding other investors. It’s become much more respectable to put money into a rocket company, although many of the players are still looked upon as at least a little eccentric. But that’s exactly the way most of the aviation pioneers were perceived in their day. Another hopeful development is the fact that some of the new players are being given a real shot at government programs, such as the DARPA Falcon and the NASA COTS.

Patrick: Russian space launch is at, or falling towards $1,000 a pound [$2,200 per kilogram] and SpaceX is targeting $1,000 a pound. That might be low enough to open up new markets. In my opinion, some of the new ventures, while perhaps not having access to as much money as Kistler Aerospace and Beal Aerospace did in the ’90s, are better positioned to accomplish more limited objectives. And while a lot of the smaller companies are having a hard time finding investors, some have. There is more realism in their technological and marketing plans than perhaps in the past.

TSR: Looking at all the alt.space and NASA VSE plans currently circulating, are you optimistic that someone will crack the space access nut soon? Or is this likely another “false dawn”, as we saw in the late ’90s?

Dave: Taking off from my answer to the previous question, it seems like we are at a point where we’ve finally got a good deal of private money being spent on some very practical approaches. Again, all the important pieces are there, in terms of technology. So I am optimistic. But there are certainly no guarantees. We need to be on guard and guide the development of the regulatory regimes in the right directions. We need people to learn the right lessons from both successes and failures to keep things moving forward. And we need to keep working hard to ensure that the commercial infrastructure that is developed is sustainable on its own. The VSE, through COTS, looks like it may provide some important synergy, but in the long term, the industry is going to have to be truly commercial—not dependent on government programs or subsidies.

Patrick: As cataloged in the book, there have been lots of failures along the way from the OTRAG in the ’70s to the present day. The most recent round of developments is, in my opinion, most encouraging. Although the regulatory regime is far from ideal and export control limits are problematic, nevertheless government policymakers are aware that this is something that should be encouraged. This is a far cry from the ’80s when the State Department would threaten to throw you in jail if you launched even a suborbital flight wholly within the United States. At the same time, no one could cite any reasonable interpretation of existing law that gave the State Department or anyone power to regulate such activities. There is a growing public perception that something is going to happen, and that perception is based on real results. In some sense the only limitation is a perceptive one. Remember, $90 billion was spent on wiring the globe with fiber optics for markets that didn't exist. When public and investor perception reaches a certain point, things will start happening—and they already are happening. So while it's hard to accurately predict the future, my opinion is that this round of new space endeavors is the most hopeful yet.

Patrick: As a parting note some Orbiter users (See “Review: Orbiter space flight simulator”, The Space Review, November 14, 2005) are working on an add-on to simulate the DH-1 in this realistic freeware space flight simulator, which should make it possible to take a DH-1 out for a test drive.

Patrick J. G. Stiennon is an experienced aerospace engineer and patent attorney at Stiennon & Stiennon, in Madison, Wisconsin. He is a Senior Member of the American Institute of Aeronautics and Astronautics.

David M. Hoerr is an aerospace consultant and lecturer in Engineering Mechanics and Astronautics at the University of Wisconsin Madison. He is a Senior Member of the American Institute of Aeronautics and Astronautics.

Doug Birkholz is an award-winning Industrial designer and principal at Inspire Design Group LLC, a product design firm in Madison, Wisconsin.

Writing as a layman, for laymen, Mark Trulson grew up in the ’60s avidly following Apollo and Star Trek equally. With 19 years of experience in the newspaper business and 10 more at a local college, he finds space-related blogging at Out of the Cradle (www.outofthecradle.net) a fulfilling change of pace.

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