Chair Force Engineer

Friday, August 05, 2011

An Atlas-Kinda Day

For the Atlas V launch vehicle program, today was a big day. The first major development was the successful launch of the Juno space probe which will study the planet Jupiter. When I heard that Juno was being launched into space, I first had to wonder whether Michael Cera would be lonely back on earth. But all kidding aside, Juno will study our solar system's largest planet in the 2016-17 time frame and hopefully tell us more about the formation of a planet that we've come to think of as a failed star. In some ways the probe is a "consolation prize" for the failed Jupiter Icy moons Orbiter, which would have used a nuclear reactor to power its ion engines. The science mission is very different, though, and the moons of Jupiter will sadly need to wait before their secrets open up to us.

The other exciting Atlas-related development was Boeing's decision to fly its CST-100 manned spacecraft on Atlas V rockets. It's interesting to note that they will be using an Atlas V 412--four-meter diameter fairing, one solid rocket booster, and two engines on the upper stage. This configuration increases the thrust margins for manned spaceflight, which is especially important when the rocket is flying the shallower trajectories which allow for successful crew escape. Having one SRB does create a small increase in the probability of first stage failure, but that's mitigated by the crew escape system that will be present while the SRB is burning. Also interesting is the two-engine upper stage. As far as I know, this is the first Atlas V payload to request two upper stage engines. The addend engine does give the astronauts some extra redundancy if one fails, although the RL-10 eries engines on the Centaur upper stages have been pretty reliable (dating all the way back to 1962.)

When manned flights of CST-100 and Atlas V start in 2015, it will be interesting to see how Boeing selects its crew of two astronauts (or "test pilots," as Boeing calls them.) They will likely choose from former astronauts who have gone to work for the Boeing company. (And there's at least one cosmonaut who works for Boeing, IIRC.) I'm certain that "astronaut" would be an interesting job listing to find on It remains to be seen on when the operators of privately-owned manned spacecraft start to hire new astronauts with no previous spaceflight experience. There's no reason to think that NASA's rigorous requirements will be eased for the private astronauts.