The Oshkosh Air Show began this week with the arrival of Whiteknight Two, the launch aircraft for Virgin Galactic'ês space tourism service. But the real aerospace future had already landed in the form of an unmanned Predator drone. The arrival marked the first flight of an unmanned aerial vehicle (UAV) to a civilian air show, requiring special FAA authorization. Drones herald pilotless flight. But more immediately, they provide a fast, inexpensive way to test new designs and materials in an industry that otherwise moves very slowly with lengthy product cycles (as with the Boeing 787). Boeing bought drone maker Insitu in July of last year.
The ostensible star of Oshkosh, Whiteknight Two, was missing not a pilot but its spaceship. (See photo.) And its spaceship, when finished, won'êt actually get to space but just very high in the sky. One year ago, I wrote about how space tourism was nigh but a new space age was not. Even space tourism is turning out to be tardy: Virgin'ês not even close to a hoped-for and hinted-at first launch in 2009.
While Virgin Galactic is a rerun of 1960s technology, efforts continue to realize the true space plane dream. Such a craft would take off from the ground, accelerate to 25 times the speed of sound, overpowering gravity and entering space before gliding at will back to earth.
The NewScientist recently described work on scramjets, a not very recent [PDF] technology idea which theoretically could propel a space plane. The article is optimistic but acknowledges that 'êsome critics to liken scramjets to nuclear fusion reactors: a great idea but technically impractical.'ê Like fusion, scramjets might consume more energy than they produce. Still, for a highly combustive ten seconds, in 2004 a scramjet attained nearly mach 10, before blowing up, currently a kind of standard practice when operating at such extremes. The next test will aim for sustained flight at a slower but still brisk pace above mach 6. Still a ways to go.