Interesting artilce from the Economist
Knight in shining armour
Jul 31st 2008 | MOJAVE
From The Economist print edition
Private space tourism is just the beginning
A COMPANY called Scaled Composites is to aircraft makers what Ozwald Boateng is to tailors. If Sir wants something bespoke but slightly outlandish, Sir has most definitely come to the right place. Burt Rutan, the firm’s founder, supervised the construction of Voyager and GlobalFlyer, two aeroplanes that flew non-stop around the world. But of the 39 craft that have been built and tested at its base in Mojave, California, since 1974, none is more extraordinary than White Knight Two.
White Knight Two is not merely an aircraft. It is the first stage of a spaceship. “Sir”, in this case, is Sir Richard Branson—or, rather, Virgin Galactic, one of his companies. What Virgin has ordered is the largest carbon-composite plane yet constructed. It consists of a single wing 43 metres (140 feet) long (an engineering feat in itself), fitted with twin booms and fuselages. The second stage, the less imaginatively named SpaceShipTwo, will be slung in the middle of the wing and lifted to an altitude of 15km. There, it will be released. It will then make its own way to the edge of outer space, to the acclamation of six fare-paying passengers.
At $200,000 a seat, that should be good business. Often, however, the most interesting thing about a new technology is not what it is designed to do, but what it can do that was not in the original specification. And, according to Virgin Galactic’s president, Will Whitehorn, the possibilities there are growing by the day. A variety of large objects other than SpaceShipTwo could be slung under the wing of White Knight Two. One application being explored is flying replacement engines for Boeing 747s around the world. White Knight Two could also launch small satellites into space at a cost of less than $2m each. And it would be a good way of taking pilotless reconnaissance drones to otherwise inaccessible places and then launching them. In the past two months Mr Whitehorn has, he says, been approached by 14 large organisations interested in using White Knight Two or buying a plane just like it. Purchasing one outright would cost $35m-40m.
The craft is surprisingly acrobatic, too. That means it is able to offer passengers zero-gravity flights. At the moment, a Boeing 727 provides such flights commercially for the Zero Gravity Corporation, a travel company. But the 727 is an ageing and thirsty vehicle. Mr Whitehorn reckons that, subject to the appropriate permissions, White Knight Two could offer zero-G flights for around $1,000 each, a fifth of the fare now charged.
Alan Stern, until recently the associate administrator of science programmes at NASA, America’s space agency, reckons the combination of White Knight Two and SpaceShipTwo could also revolutionise the study of atmospheric physics. Routine flights into the upper atmosphere by White Knight Two on its own would offer opportunities for regular experimental work at high altitude. That would make it possible to study the heart of the ozone layer. But the combined craft would also allow access to the “ignorosphere”, a frustrating region 50-80km above the Earth’s surface that is too high for conventional aircraft and too low for satellites. This would permit the study of so-called noctilucent clouds, the highest in the atmosphere, which are thought to have an important role in climate change. White Knight Two and SpaceShipTwo, says Dr Stern, could fly more experiments to noctilucent clouds in six months than NASA has managed in 40 years. The $200,000 price of a ride is about a tenth of the cost of the small, unmanned “sounding” rockets now used to investigate this region.
Perhaps the most intriguing research to come out of the White Knight project, however, is in aeronautic design. Pending patents, Mr Rutan is cagey about the details. But he says that building the aircraft has demonstrated something “very significant” about the main structural support on a wing (known as a wing spar) and that, as a consequence, his company’s technology will allow the construction of an aeroplane of “any size”.
If true, that is very interesting indeed. In theory, White Knight Two already has the capacity to carry a single-passenger spaceship that is capable of getting not just into space, but into orbit. Carrying one person into orbit in this way is probably not commercially viable. But if a larger high-altitude jet could be built, larger orbiters would also be possible. “We’ve made layouts of subsonic launch airplanes that could put six people in orbit off this airport,” he says. But the next-generation aircraft would have to be bigger. “Much bigger. Much bigger,” says Mr Rutan, with a twinkle in his eye.