Chair Force Engineer

Monday, April 25, 2011

The New Mercury-Atlas

When I saw this story on, my eyes were immediately drawn to the graphic of the Boeing CST-100 space capsule on top of the Atlas V rocket. While previous artwork from United Launch Alliance showed a generic capsule on top of the Atlas, this is the first illustration of the complete CST-100 + Atlas V 401 stack. Apparently this is an unmanned cargo configuration due to the missing Launch Escape Tower (unless Boeing has some ideas similar to SpaceX for crew escape.)

There's no elegant way to mount a capsule to the skinny Atlas V rocket and its even-skinnier Centaur upper stage (as long as the Centaur isn't wearing its 5-meter fairing for large payloads.) So Boeing went with a short and wide tapered section between the CST-100 service module and the Centaur upper stage. By eyeballing the picture, it appears that the CST-100's diameter is around 4 meters--pretty close to the 3.8 meter diameter of the Atlas V. This would put the CST-100 in a similar size-class as the Apollo spacecraft. It should be able to carry three astronauts in comfort on long missions, or 5-6 for emergency rescue missions from the ISS.

I was reflecting on the early orbital spaceflights which used the Mercury spacecraft and Atlas booster. Since Boeing owns the manufacturer of Mercury (McDonnell Aircraft) and wants to use the Atlas booster, why not just rename the CST the Mercury? If nothing else, enthusiasts for manned spaceflight can be very nostalgic.