Lights out for Ares?

New Scientist’s “Short Sharp Science” blog is not very hopeful about the rocket that’s supposed to take us to Mars. Apparently, there was an oversight in the safety systems around the Orion (the space capsule with the people inside) and the Ares rocket’s big, explosive Solid Rocket Boosters (SRBs):

If the accident occurred during the time of high wind blast – at least the period between 30 and 60 seconds after launch, maybe longer – an escaping Orion wouldn’t be able to pull clear of the fragment cloud. Something similar happened in 1998, when a Titan IVA rocket exploded about 40 seconds after launch. It had two somewhat smaller SRBs, but the total load of solid fuel was only a little less than an Ares I SRB, and various other aspects were broadly similar. The debris cloud generated in that accident was half a kilometre across within about 3 seconds, and about 5 km across within about 20 seconds.

But that analysis discovered a much more serious problem, one that nobody had noticed. The big problem is that much of that debris is big chunks of flaming solid fuel, still burning at over 2000 °C. For an accident anywhere in that vulnerable period, Orion will be inside the blazing debris cloud for its whole descent. And its parachutes are nylon, which melts at about 200 °C. They will overheat and disintegrate, and the capsule will crash.

You can imagine the headlines. Even though there’s only a 0.3 percent chance of this ever actually happening, that’s too much for NASA’s safety folks. And there’s not much they can do about it, short of – and this is a serious suggestion – replacing the chute with a fold-out helicopter blade.

Otherwise, it looks like something less colossal with liquid fuel instead of the solid kind will be the only way up.