DARPA has just announced its latest ambition, and this one's a doozy. Jumping into the low-cost orbital vehicle arena, DARPA plans to develop a hypersonic space plane capable of reaching orbit at a cost that is less than one tenth of current orbit-capable vehicles. Oh, and they'd like the spaceplane to be a robot, too.
The idea is still in its concept phase, but that hasn't stopped DARPA from giving it a sweet designation and a list of awesome theoretical capabilities. Welcome to the dawn of the Experimental Spaceplane (XS-1) program. The XS-1 is slated to be fully reusable and to be capable of spur-of-the-moment jaunts into low orbit. There, it will be capable of launching small to medium-sized satellites all by its robotic self.
This isn't the first time that DARPA has opened the door for a reusable space plane. In 1999 NASA unveiled the X-34, which was cancelled due to high costs in 2001. Then there was the X-37B, a robotic space plane capable staying in orbit for months (or years) at a time. Neither of these projects, however, was capable of daily missions to orbit or such low projected mission costs.
Exactly what the final version of the XS-1 will look like is still up to debate. In the words of project manager Jess Sponable:
"How it's configured, how it gets up and how it gets back are pretty much all on the table — we're looking for the most creative yet practical solutions possible."
We'll keep an eye on the development of the XS-1. An advancement of this magnitude would advance not only our satellite launch capabilities, but would constitute a leap forward in hypersonic flight as well.