A “Moore’s Law” for space transportation: what will it take?
by David M. Hoerr
|The applications of low-cost space transportation are going to be applications created by low-cost space transportation, which by definition do not and cannot exist until low cost space transportation is a reality.|
So, will market demand drive a Moore’s Law for space? It certainly hasn’t so far. There just aren’t any mass markets driving demand for “faster, better, cheaper.” Current and projected markets are too small to make much of a difference; the comsat market is essentially flat as far out as we can see. The President’s Vision for Space Exploration, even if it goes forward in a substantial way, will still only result in a total demand for launch services that is tiny compared to terrestrial transportation markets. The long-sought “killer app” for space that will drive demand has not yet appeared, nor is it likely to do so. Yes, there are many ideas for what those markets might be, and legions of space enthusiasts and visionaries who have definite ideas about what a future “dynamic, evolving” space industry could be like. But we just don’t have enough experience, enough opportunity, or enough infrastructure to know what will and what won’t work. To paraphrase Herbert Kroemer, winner of a Nobel Prize in physics and author of the “Futility of Predicting Applications” lemma, the applications of low-cost space transportation are going to be applications created by low-cost space transportation, which by definition do not and cannot exist until low cost space transportation is a reality. The markets simply do not yet exist.
What about a market for suborbital tourism and perhaps scientific research flights? It remains to be seen just what kind of market will actually be there. But short, suborbital hops have much more in common with weekend sightseeing flights around the local airport—which do represent a large portion of general aviation activity—than they do with revenue-earning commercial air transportation operations. Most of the players in the suborbital arena, including Rutan, recognize that orbital flight is where they need to be heading. After all, transportation is about going somewhere, and as Heinlein famously put it, “once you’re in orbit, you’re halfway to anywhere.” There’s a whole universe out there!
Well, then, will technology kick it off? We certainly have a solid foundation of rocket and space technology developed over the past 60 years of military and other government programs. But again, that hasn’t done it yet. Because the market for launch services has been so static and limited, the launch vehicle industry has not exactly been a hotbed of innovation. While there has been a host of upstart rocket and launch vehicle companies struggling over the past 25 years to gain a toehold, the market is still dominated by a handful of conservative companies and government agencies. The only new entrants that have managed to stay alive are Orbital Sciences Corp. in the US and a few foreign space agencies that have developed their own space launchers. None of these have done anything differently, nor done much to move us toward a new paradigm in space.
|New technologies will become major factors when there is a market and industry vigorous enough to require them. In the meantime, new and unproven technologies are more likely to increase costs than to lower them.|
But do we need, as some observers seem to assume, new technological developments to make low-cost space transportation a reality? Perhaps some exotic new form of propulsion to replace “inefficient” chemical rockets, or new materials based on carbon nanotubes or some such? Those things may make a difference—some day. But their lack has not been holding us back. As long ago as 1967, Max Hunter wrote a paper titled “Commercial Space Transportation Possibilities” in which he applied air transport operational and cost analysis methods to space transportation, based on 1960s technology, and concluded that there were no fundamental reasons why costs per pound to low Earth orbit (LEO) could not be a few dollars (in then-year dollars). More recently, Gordon Woodcock’s 1988 paper titled “Lower Bounds on Launch Costs” likewise concluded that the lower bound should indeed be orders of magnitude lower than current costs, even without resorting to as-yet-unavailable technologies.
New technologies will become major factors when there is a market and industry vigorous enough to require them. In the meantime, new and unproven technologies are more likely to increase costs than to lower them. What about Rutan’s SpaceShipOne and Musk’s Falcon? Well, neither of these vehicles is based on any breakthrough in technology. What they do embody is clever and competent engineering, plus efficient engineering management. And that may be enough.
If we can’t create the markets, and we don’t need new technology, what we can do to get costs moving downward? How about increasing the supply of space transportation, in a really usable form? It’s a well-known fact of economics that an increase in supply is what puts downward pressure on prices, not an increase in demand. And forget about the “glut” of launch capacity that we supposedly have right now. That capacity is based on expendable rockets that are really only good for the large, expensive, unmanned satellites that are launched by the few dozens per year. What we need to get costs really dropping are space transports—not one-shot “skyrockets”—and lots of ’em!
A small, flexible, affordable space transport that constitutes an investment, not a one-use item, can be the catalyst for setting off a Moore’s Law-like downward spiral in space transportation costs. A space transport that can be owned and operated by as many companies, agencies, institutions, and even individuals as possible. That will provide the only kind of environment in which innovation, experimentation, and expanding opportunities will be possible. Without those things happening on a larger and larger scale, the real applications for space transportation won’t have a chance of being developed. The reason that legions of software developers wrote programs for MS-DOS is that there were lots of machines out there running DOS. In an expanding, world-wide fleet of such vehicles, owners will find they have extra capacity on their hands. That in turn will put pressure on them to reduce costs and lower prices. The lower prices and customer-friendly nature of smaller, flexible vehicles will encourage new customers to turn their dreams and concepts into actual space operations. Then new customers will come forward. Then the new markets will develop. As the markets grow, the demand will grow, encouraging and justifying further developments in space transportation systems and technology that will yield further reductions in costs.
|A small, flexible, affordable space transport that constitutes an investment, not a one-use item, can be the catalyst for setting off a Moore’s Law-like downward spiral in space transportation costs.|
Where would the buyers of these space transports, which would finally be true spaceships, come from? Proposals for all sorts of space ventures from the President’s Vision, to orbital hotels, to comsat salvage, to lunar settlements, to asteroid mining, to colonizing Mars have been floated. None of them have gotten much past the talking stage. Why? No spaceships. Lots of people would love to get their hands on a real spaceship. The major nations of the world—the US, Russia, China, Europe, and Japan—have invested billions to develop space launch systems, and numerous smaller nations such as Israel, India, and Brazil have worked hard to develop their own capabilities. Most nations save the poorest have at least some kind of “space program.” All around the world, there are people, companies, and organizations that want the capability to send their payloads into space, on their terms and on their schedules, and at prices they can afford. Payloads and people.
Yes, people. What nation or organization wouldn’t want to be able to send their own astronauts into space, if it’s affordable? A key ingredient to getting things cooking in space is to get more people in space. The more people we have actually working in space, the more demand will be generated. People do things. People think of new equipment, new tools, new stuff, that they need. People buy things; robotic platforms and devices do not. What we need are greatly expanded opportunities for people in space. Today, the only access to space for people is by means of the very tightly controlled, very expensive U.S. and Russian systems. The Chinese are not yet in a position to offer services to anyone outside of their own space program. Japan and the European community have invested billions toward the development of human spaceflight capability without achieving it. There would be no lack of customers for an off-the-shelf human spaceflight capability costing a fraction of what it would take to develop from the ground up.
So what should this suggest for launch vehicle/space transport developers? Here’s where the clever engineering comes in to play. We need a space transport that can be developed inexpensively, produced inexpensively, and operated inexpensively. Such a vehicle could then be sold to a wide range of owner/operators, which would form the basis for a truly dynamic, growing, and evolving space industry. That pretty much rules out government-developed heavy lift boosters, Big Dumb Boosters, microsatellite launchers, mass produced expendables, and exotic scramjet-powered spaceplanes. Sure, some of those types of vehicles will have a place in space transportation in near term, and perhaps in the far term. It’s just that they are not suited to bring about a revolution in space transportation now.
|A strategy of selling space transports rather than launch services will provide a greater return on the investment required to develop these vehicles, and thus provide a more attractive business case for those who will need to make the necessary cash available.|
What we need is a small, flexible, affordable vehicle. One that is small enough to be affordable both to purchase and to operate. One that is small enough to be flexible, allowing high flight rates and providing a better match for demand that, realistically, will grow slowly, at least at first. It doesn’t have to be big enough to haul the latest comsat to geosynchronous orbit; there are acceptable ways to do that now, and the market is tiny. It doesn’t have to be big enough to haul massive space stations or interplanetary “cruisers” into orbit. The vehicle need only have enough useful payload capacity to get things done. It certainly doesn’t have to be 50,000 pounds; it can probably be less than 10,000 pounds. According the U.S. Bureau of Transportation Statistics, over 180 million tons of goods are transported across the country every year in shipments of less than 1000 pounds. Clearly, small “payloads” play a major role in the terrestrial economy, and can be expected to do so in space. The Douglas DC-3, which ushered in the era of modern commercial air transportation, could carry a total payload of somewhat less than 7,000 pounds. Finally, it needs to be a passenger transport as well. It needs to be designed, as commercial aircraft are today, for safely carrying people from the beginning.
Such a vehicle will most likely be a two-stage-to-orbit (TSTO) vehicle; ballistic, not winged. That is probably the simplest way to do it. Not the only way, of course: there is certainly more than one way to build a TSTO. But something like that. In the 1990s, a consensus developed within the space industry (including the “establishment”) that single-stage-to-orbit (SSTO) was the only way to go for lower cost spaceflight. Unfortunately, SSTO’s are just a little too hard to do. Perhaps we can develop a new consensus that a small, affordable, TSTO is the way to go. Rutan and Musk, as well as a host of other “alternative aerospace” pioneers around the world, are beginning to show in dramatic ways just what is possible without government mega-programs and their corresponding mega-budgets. SpaceShipOne should go a long way towards dispelling the myth that “man-rating” a space vehicle is exorbitantly expensive.
Finally, and perhaps most importantly, a strategy of selling space transports rather than launch services will provide a greater return on the investment required to develop these vehicles, and thus provide a more attractive business case for those who will need to make the necessary cash available. This should be a consideration for those companies involved in developing suborbital vehicles as well. Sales of affordable spaceships can be expected to significantly outstrip revenues from launch services in the near- to mid-term. The 2003 NASA/Futron ASCENT study of future space markets concluded that if cost per pound to orbit decreases significantly, the space transportation market will actually shrink in terms of sales dollars. However, as prices for space transportation fall and new markets develop, we can expect that the market for launch services will grow exponentially and sooner or later outpace the market for vehicles that will likely grow only linearly. But to get to that point, we need healthy, growing, and profitable space transport-building companies.
In the early decades of aviation, the only people making money were the ones building and selling airplanes. People bought airplanes before they had any profitable use for them. As more airplanes were sold, more people could experiment with them to figure out how to make money, and the airplane manufacturers could use those revenues and attract additional investments to pay for the enhancements, improvements, and technology developments that reduced costs and ultimately gave us the air transportation industry that we have today. The supply of airplanes led to the development of the demand for air transportation services. Let’s take a similar “supply-side” approach to opening the space frontier!