The replica Wright Flier that didn't fly at Kittyhawk last week brings to mind the Mars flier that didn't fly anywhere, ever. Back in 1999, when I was starting to work on Mapping Mars, the idea of a Mars aircraft that would cut through the planet's skies on the Wright brothers' centenary had caught various imaginations - most notably that of Norm Augustine, former CEO of Martin Marietta/Lockheed and an aerospace industry legend. Augustine picked up the meme from a physicist at Princeton, Edgar Choueiri, and in his turn he infected NASA administrator Dan Goldin. In February 1999, when NASA and the French space agency, CNES (then in the grip of science minister Claude Allegre, a geophysicist who wanted planetary science to play a greater role in French space planning) held a joint Mars meeting in Paris, there was much talk of a cheap Mars aircraft mission that would arrive at the planet on December 17th 2003. Briefly, if I recall correctly, the flier actually made it into NASA's budget as the first in a series of Mars "micromissions" to be launched as piggyback payloads on Ariane 5s. One old friend attending the Paris meeting told me that he wasn't sure maps of Mars were worth a book - and maybe I should write the story of the airplane instead. (You can read more about the Mars Flier, and other Mars aircraft projects, in an article I wrote for Air&Space Smithsonian that's archived here)
Obviously, as we now know, this didn't happen. Didn't get close to happening. Budget too tight, schedules too tight, NASA internal politics too difficult, a whole lot of other things. In retrospect it should have been obvious that it wasn't going to happen. But things were genuinely different then - in that there was a pretty absurd level of optimism about what might be possible. Back then there was going to be a Mars lander in late 99 (Mars Polar Lander) and another in 2001; the 2003 mission slot was going to carry a rover very like one of the Mars Exploration Rovers that reach the planet in January - but it would also carry a small rocket with which to launch a cache of rock samples into orbit round Mars. 2005 would have seen a second such sample-gathering-and-launching rover, and a French mission that would have landed a network of geophysics sensors - the Netlanders - on the planet while also scooping up the samples that were cached in orbit and taking them back to earth. All this on a tightly constrained budget. In a world where all that was possible, adding an aircraft designed to unfurl its wings while falling towards the surface from orbit and use them to fly through the thin Martian air seemed, well, plausible.
By the end of that year, with Polar Lander and Climate Orbiter lost, things looked very different. The '01 lander was cancelled, as were the '03 and '05 sample return missions; their rovers were resurrected as this year's Mars Exploration Rovers (which ended up a lot costlier than the estimates had them in 1999). A replacement sample return mission isn't going to get underway any time soon - not until next decade at least. After various programmatic metamorpheses, the Netlanders died too. France no longer has any plans for Mars missions.
In retrospect it feels as if there a powerful reality distortion field extended over all these discussions. Two cheap(ish) Mars missions had worked in 1997; the Martian meteorite ALH84001 had been headline news around the world; the cheap spacecraft in the Discovery program seemed to be doing good stuff on a budget; it was a time for buoyant spirits. The fact that there was a Mars programme seemed so wonderful in itself that worries over the abilities of NASA and JPL to make a go of it were pushed aside. The cracks were beginning to appear (the '01 mission was ceaselessly descoped and threatened with cancellation) but it was still possible to ignore them. And why shouldn't you? It was a dead cert that if people didn't believe the Mars program could succeed then it wouldn't. Believing didn't guarantee success - but not believing guaranteed failure. Planetary science is so full of mishaps and miscalculations that its practitioners kind of have to be optimists. As Steve Squyres, the principal investigator on this year's rovers, puts it, if you are only interested in the results - if you're not going to enjoy the process of trying to get them come what may - you ought to get into another line of science.
And eventually a human aircraft will fly through the skies of Mars. It may not do so on a significant anniversary, and it may not stay up very long. But optimists will keep trying to sell such missions until one of them gets lucky.