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Skylon
The Skylon single-stage-to-orbit reusable spaceplane, currently under development in the UK. According to two retired ESA managers, this vehicle is impossible. (credit: Reaction Engines Ltd.)

Space tourism is no hoax


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In 2004, the European Space Agency released a design study called “Human Missions to Mars: Overall Architecture Assessment”. This study was undertaken after a decade of work, notably by David Baker, Jim French, and Robert Zubrin, which established that local propellant production using the Martian atmosphere would be a key technology for practical human access to the Red Planet.

The strategy seems to be to ignore the crucial enabling technologies and strategies in pursuit of a proof that manned spaceflight lies somewhere between exceedingly difficult and downright impossible.

Nevertheless, the ESA study totally ignored this work, and proceeded instead to design in considerable detail a Mars mission on the classical 1950s model. The vehicle would mass 1,357 tonnes on departure from low Earth orbit, and would require about 20 launches of the giant Energia rocket over 4.6 years to assemble—that is, every single mission would require more heavy-lift launches than the entire Apollo and Skylab programs together. The fruits of this titanic effort: just 30 days on the surface of Mars for only half of the crew of six.

Now they’re at it again. Last week Space News published a commentary authored by former ESA director of launchers Fredrick Engstrom and former head of future launchers Heinz Pfeffer titled “Space Tourism is a Hoax”. Again, the strategy seems to be to ignore the crucial enabling technologies and strategies in pursuit of a proof that manned spaceflight lies somewhere between exceedingly difficult and downright impossible.

The article begins by slamming “con men” who are fleecing the gullible rich of $20,000 or $200,000 a ticket for the impossible dream of an orbital space flight. The accused parties are not named; nor is it even clear whether the writers are attacking local crooks unknown to most of their readers, or established companies such as Virgin Galactic and Excalibur Almaz.

Certainly, David Ashford of Bristol Spaceplanes has estimated that prices could fall as low as $20,000 per visitor to a space hotel after about fifteen years of spaceplane development. He has not to my knowledge tried to sell anyone a ticket on that basis, though in 1994 he did sell a design study under contract to ESA, as described in his book Spaceflight Revolution. His study concluded that an operational prototype of a small orbital spaceplane could be built with existing technologies for $2 billion. Such a vehicle would be capable of launching the virtuous spiral over a decade or two towards a thousandfold reduction in the cost of access to space.

It is not clear whether Engstrom and Pfeffer have read Ashford’s study, or if they have whether they feel hoaxed by it (it was independently reviewed by the British government, who found no obvious flaws in it). After mentioning that today a flight is possible with the Russians for about $20 million, Engstrom and Pfeffer point out that this is not remotely available to most people, and go on to argue: “There is no business in space tourism. This is due to basic laws of physics.”

It is hard to be sure whether our authors—former directors at ESA—are deliberately witholding information, or whether they are genuinely ignorant of basic space launch physics and technology. Their argument is that spaceflight is so expensive because the rocket equation forces rockets to be huge and multi-stage in order to get into orbit: “you can never get around the fact that you need big machines that are staged to reach orbital speed.”

It is hard to be sure whether the authors—former directors at ESA—are deliberately witholding information, or whether they are genuinely ignorant of basic space launch physics and technology.

Certainly, as Engstrom and Pfeffer say, rockets have to be “very big, complicated machines”. So for that matter is an Airbus A380, or an ocean cruise ship. But that doesn’t seem to stop tourists from using them.

One can reach orbit “only by chemical rocket propulsion”, we are told. This is a blatant untruth. Rocket flight through the lower atmosphere is in fact grossly inefficient, because it carries its own oxygen when it does not need to. The atmosphere can provide both reaction mass and oxidizer. Because of the exponential character of the rocket equation and because oxygen is several times heavier than the fuel it combusts, a small amount of help from the atmosphere does a lot of good in getting the mass ratio of a vehicle down to a manageable level.

Thus Bristol Spaceplanes’ Spacebus design uses jet engines to accelerate to Mach 4 before releasing its orbiter stage. The German Sänger project planned to go to Mach 7 in air-breathing flight before separation. And the single-stage Skylon, currently under active development in the UK thanks to a combination of private and public funding, uses combined jet-rocket engines that would run on atmospheric oxygen up to Mach 5 before switching to onboard oxygen.

Projects for reusable winged aerospace vehicles such as these have been widely discussed in Europe ever since the 1960s. It is hardly likely that top managers at ESA would have been unaware of them. And indeed, Engstrom and Pfeffer are presumably referring to these studies when they say: “Reusable systems have been studied extensively all over the world, and they are found to be horrendously expensive.”

This statement flies in the face of logic. In what sense is a vehicle which can amortize its manufacturing costs over a couple of hundred flights more expensive than one which can only carry a single payload? Certainly the development cost of a reusable vehicle may well be higher. But its operating cost will then be lower, provided that a reasonably high launch rate can be achieved. Are Engstrom and Pfeffer then arguing that a high launch rate is impossible? Perhaps there is no market for large-scale launches to space? Might space tourism provide such a market? Apparently not, because “there can be no business case for space tourism”, so that’s excluded, then.

Our authors comment that the full cost of a Space Shuttle launch has been estimated to be $1.5 billion, implying that this proves their point. Isn’t the Shuttle reusable? Well, not very much. It consists of a huge tank that is destroyed on every flight, two boosters which are dumped in the Atlantic and have to go back to the factory to be recycled, and an orbiter which, yes, is reusable after a fashion.

When I recently flew back to London from Berlin, I was waiting in the terminal at Schönefeld as the Airbus A319 flew in. It drew up in front of the terminal building and was immediately surrounded by ground crew. While the passengers disembarked, their baggage was unloaded, a fuel hose was hooked up to the belly of the aircraft, and our baggage was loaded. A man strolled across in front of the engines, peering at each one in turn and spinning the turbines by hand. While this was going on we embarked, and the aircraft was back in the air within an hour or so. That was a reusable vehicle!

I believe it would not be going too far to say that the European Space Agency is firmly opposed to manned spaceflight.

The Airbus made two flights that day, as it probably had for most of its working life. The Space Shuttle orbiter is being worked hard if it makes as many as two flights per year. (In 1985—the heyday of the Shuttle, before Challenger exploded—Discovery made four flights, and in 1983–1985 Challenger itself managed three flights three years in a row, records which have never been matched by any of the other orbiters.) For over eleven months of the year the orbiter is sitting on the ground being cosseted by highly-paid engineers. But then, of course, the Shuttle is an experimental vehicle, not an example of a practical, economical reusable space transport system. Such as a future space tourism industry, for example, might want to use.

I believe it would not be going too far to say that the European Space Agency is firmly opposed to manned spaceflight. They are happy to talk about it and to spend public money on studying it, they are happy to contribute an occasional astronaut to wave the flag on an American or Russian space station (yes, a large fraction of the ISS is built in Italy, but would those modules be in space now if Congress had cancelled the ISS in 1993?). But they seem to have an institutional aversion to actually doing it for themselves.

Consider their latest project: upgrading the Automated Transfer Vehicle-Ariane 5 system, firstly to a recoverable capsule, then to a manned spacecraft for four astronauts, perhaps by 2020. The result—a throwaway rocket carrying a capsule for a tiny number of government specialists to fly once every few months—would be scarcely distinguishable from the Apollo-Saturn 1B which first flew over forty years ago.

This is being proposed, not as a reconstruction of the historic Apollo flights—as one might reconstruct Columbus’ voyage to America in a replica wooden sailing ship, to demonstrate how it was done then and how much progress has been made since—but as the first means of choice for European astronauts to go into space for decades to come. According to ESA, this is “achieving greatness”, “pushing the boundaries”, and “staying one step ahead”. They must be bonkers.

What is the alternative? Firstly, to recognize that the era of government domination of manned spaceflight is drawing to a close. That era, motivated by prestige, science, and spinoff, has done all it can. The peak in manned launches to orbit actually came as long ago as 1985, when 11 launches (nine Shuttle, two Soyuz) carried 63 people into space. There will be no further progress in manned spaceflight until commercial factors come to the fore.

There may be a few government spectaculars: flights to the Moon and Mars, say. They will not be sustainable, and they will be cancelled. If we are lucky, they will be like Apollo and be cancelled after achieving their initial objective. If we are not so lucky, they will be like the Soviet Moon-landing program, Europe’s Hermes manned spaceplane project, or any number of US Shuttle-successor initiatives, and will be cancelled before they ever fly.

Second, we must recognize that developing private space exploration, or space tourism, is a chicken-and-egg situation. There are no laws of physics forbidding large-scale private passenger access to orbit, but there is still a lot of work to be done developing systems and markets. A reasonable prospect for, say, 2015 is a small private space station being visited monthly by half a dozen clients at a time for a few million dollars a head. The mass market will not come until much later.

Third, public space agencies should have a duty to support the expansion of business in space. They seem to have no qualms about doing this when satellite communications or navigation is involved, so why not space tourism?

Large-scale space tourism is not a hoax. It is a realistic future possibility.

Fourth, the general perception that space tourism is somehow frivolous has to be overturned. On the contrary, it will be vital to creating future business opportunities in space. Government science is always nice to have, and it has given us impressive insights into our place in the solar system, but only a large-scale commercial passenger market can create the demand which will drive forward progress in space—first towards reducing the current absurdly high launch costs, and later towards making use of the natural resources of space.

Reading between the lines of Engstrom and Pfeffer’s commentary—their unwillingness to consider a step-by-step approach to space tourism, their manipulation of physics to make it appear to support their case, their criticism of NASA Administrator Charles Bolden for welcoming the growth of a space tourism industry—it seems clear that these two top former ESA managers want to avoid seeing private passengers travelling into space, just as their colleagues on the 2004 Mars mission study seemed to want to avoid actually sending astronauts to Mars. One can only speculate as to why this should be the case.

Large-scale space tourism is not a hoax. It is a realistic future possibility, and can be achieved by steady development from the situation in 2009 of two passengers per year to the ISS (Charles Simonyi and Guy Laliberté).

Modern civilization is founded on the revolution in worldviews that reached a breakthrough in the eighteenth-century Enlightenment. This intellectual revolution is not yet finished. When large numbers of successful middle-class people are enabled to see their home planet from space, current trends towards a sense of global human identity will be powerfully reinforced, and a renewed sense of the direction of progress powerfully inspired, with incalculable but presumably enormously beneficial effects on subsequent human history.

Space agency elitism has already retarded this process, but so long as the global economy remains healthy we will get there in the end.


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