SpaceShipOne has unleashed yet another wave of wishful thinking by the alt.space community. The same people who enthused over DC-X, X-33, and Rotary Rocket are at it again, filling cyberspace with claims that SS1 is the first successful private spaceship and will usher in the long-awaited age of private, profit-making space travel.

The only person who seems to have a realistic view of SS1 is Rutan himself -- but most people seem to be ignoring what Rutan says about his own design, and quoting the opinions of others who don't have a fraction of his experience in aerospace design.

I'm a strong proponent of privatizing manned space and getting it out of the political arena. But we must separate the facts about

SpaceShipOne from the myths.

A) It's not a spaceship or even a precursor to one. The energy required to boost SS1 into orbit would be about 50 times what it currently expends to make its short zoom-climb into "space".

There is no way a single-stage rocket plane built with existing materials can reach orbital velocity, even if it used real rocket fuels instead of SS1's mixture of rubber and laughing gas. And the trick of dropping SS1 from the White Knight carrier aircraft won't help much in gaining orbital velocity. The air-launched rocketplane configuration reached its natural performance limits with the X-15 (and even the X-15A-3 had to use disposable fuel tanks to reach Mach 6).

Even more serious is the need to dissipate that x50 extra energy during reentry. SS1 borrows from Max Faget's original Shuttle design the concept of flying a spaceplane belly-first (that's "stalled" in pilot language) in the early part of reentry so it will loose most of its velocity at high altitude before it hits the thick lower air. Rutan has invented a neat way to make SS1stable in stalled flight, but I don't see how his "hinged P-38" configuration could work at orbital velocity and heating loads.

SS1 is really a stuntplane intended to whip up public interest and favorable news media coverage. Everything about the project -- the rat-shack high desert Right Stuff ambiance of Mojave, the air-launch format, the cute round portholes, even the 63-year-old test pilot -- is carefully calculated to push the "spend money" buttons in the brains of the aging Baby Boomers who are the only sane people who still have a romantic passion for space travel.

Real free-market space tourists

will fly someday, but like Dennis Tito they will fly in cheap ballistic spacecraft that land by parachute. No private company will accept the huge payload and safety penalties that a winged configuration incurs.

B) It's not even a viable vehicle for the "suborbital tourism" market. SS1 is narrowly designed around the X-Prize competition and lacks many features customers would demand. Rutan has made it clear in recent interviews that SS1 will go to a museum not too long after the X-Prize is collected, and a bigger vehicle will be made for initial tourist flights. He believes that a viable tourist spaceplane must have major improvements: Longer time in zero-g so passengers can unstrap, abundant room to float around in, big windows to see space through, 6-10 seats to spread out the overhead costs.

The big question is: Is is possible to stretch the basic WK/SS1 configuration to meet these goals? Some enthusiasts suggest that SpaceShipTwo is already half-built in a hangar somewhere. If so, it would have to be a pretty big hangar.

The problem with all aircraft-launch concepts is that as the launched vehicle scales up, the carrier airplane scales up even faster and soon the combination is too big and too heavy for any runway at Mojave Airport. To see what a real base for winged spaceplanes might look like, check out the gigantic hangar and endless runway at Groom Lake (Area 51).

C) It's not clear that a real demand for suborbital tourism exists. While looking at a photo of Mojave Airport a while back, it occurred to me that some aircraft already parked there meet most of Rutan's criteria. There are many first-generation wide-body airliners in storage at desert airfields.

With fewer seats and more padding, they would be equivalent to NASA's famous "Vomit Comet" and could be flown in zero-gee parabolas. Put some space images on the windows and you have most of the suborbital tourism experience for a longer time at a much lower cost. If the suborbital tourism market really exists, why isn't somebody doing this?

One might say that this would be fake suborbital flight, like a good copy of the Mona Lisa, which would lack the appeal of the real thing complete with real FAA-issued "civilian astronaut wings". But shouldn't the army of rich people allegedly wanting to pony up ~$100,000 for the real thing be willing to pay ~$2000 for the Vomit Comet experience? Would anybody want to buy or steal the original Mona Lisa if copies of it weren't selling?

There have even been one or two firms that offered zero-g flights for scientific experiments. Why has none of them branched out into "space tourist training"? It seems to me that if there really were a significant number of people who would actually pay big money for a suborbital flight (not just say so in a survey), there would already be a converted L-1011 making parabolic zooms above Mojave right now.

D) Burt Rutan is not the right guy to design profit-making tourist spacecraft. SS1 is a logical extension of Rutan's long history of designing one-off stuntplanes for rich sportsmen who want to set a record, or homebuilders with a garage going to waste. These aircraft are intended to make a few test flights plus one to win the trophy or impress the neighbors, and then be retired to a museum.

They are works of art, not commercial airplanes designed to serve the public and make money for their owners. Rutan doesn't consider mundane issues like maintenance costs or fatigue life, any more than Michelangelo calculated the potential gate receipts at the Sistine Chapel. On some of his aircraft, you have to saw a hole to replace a component that fails! It's no surprise that the only attempt to market a Rutan design for general use (Beech Starship) was a complete failure.

Rutan's airplanes are the modern equivalents of the unlimited racers and long-endurance planes of the 1920-40 era. Aircraft like the Granville Brother's GeeBee and Ryan's Spirit of Saint Louis explored the limits of technology, and for that very reason could not become useful fighters or airliners without massive redesign by regular engineers who had to allow for the needs of the real world. There's a huge difference between a GeeBee and a P-36. I think the differences between SS1 and a reliable, long-lived tourist spaceplane will be just as great.

Also, Rutan's pet structural material is carbon-based composites. This class of materials was designed specifically for transonic aircraft. For hypersonic space vehicles it has the severe drawback of igniting and burning at fairly low temperatures. Rutan's firm Scaled Composites made the outer shell of the DC-X military stunt rocket, which actually set itself on fire during a fast landing from the backwash from the rocket exhaust plumes. An aluminum skin would never have noticed this heat, which is far less than that of a reentry. Any serious rocketship made out of composites will need serious heat protection, probably more than one made out of plain old aluminum.

So if I had to bet my money on someone to build the first real private spaceship, it wouldn't be Burt Rutan.

Of all the players currently in the running, Elon Musk is the only one who seems to have both the right technical concept and a sufficiently deep pocket to perfect that concept without outside investors.

The problem with Musk's Falcon boosters is that they aren't sexy spaceplanes. They are just regular boring rocket boosters that look like storage tanks. The cheap construction and recovery features are invisible and don't make exciting stories that will appeal to the technically illiterate.

But dull, boring boosters that reduce the immense cost of orbital launches are just what we need right now. I am not convinced that flying a few rich Baby Boomers on short joyrides can possibly be the basis of a sustained human presence in space (even after reading a dozen articles by alt.space promoters that try to make this case).

An orbital booster that cuts the cost of reaching LEO by a modest factor of x5 or x10 would have far more impact. It would change the whole space industry beyond recognition and make real private space flight affordable. That is the private spaceship the world needs -- not Burt Rutan's stuntplane.

Jeffrey F. Bell is Adjunct Professor of Planetology at the University of Hawai'i at Manoa. All opinions expressed in this article are his own and not those of the University.

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