Tuesday, September 23, 2014

Blasts from the past

Hey, gang--long time, no see. It's not that I've been ignoring you, it's that life has been a little busy lately (and will soon get busier). But that's the usual blogger excuse. Let's talk about something more interesting, like... rockets.

There has been lots of space in the news lately. NASA's next-generation Orion spacecraft hit some milestones. Boeing was chosen as the lead contractor for a "space taxi" into Earth's orbit. Blue Origin is pitching new engines to use instead of the Russian-made RD-180s. And of course the Maven probe to study Mars' atmosphere arrived safely.

So it's fun to think that all this does indeed point to a real renewal of interest in deep space exploration. Indeed, in the next five or so years, the Orion capsule is planned to be on a spin outside Earth's orbit, just to see what she can do. It will be launched on top of the (unimaginatively named) Space Launch System, which bears some resemblance to the Apollo program's mighty Saturn V:

Tall. White. Rocket-like. Yep, fits the profile.

It should work well! But there were times before we figured out the whole rocketry thing that some really epic plans were on the drawing board. I've written a little about the U.S. proposals for nuclear rockets; here is an fascinating look at Russian plans along the same lines:
By the end of 1967, the Kremlin gave the green light to Vladimir Chelomei to work on the preliminary design of the UR-700 rocket as a backup to the troubled N1. Unlike the N1, Chelomei's rocket would be assembled out of components built in Moscow and transportable by rail. Even more importantly, it would use just 12 engines on its three stages, instead of 42 on the boosters stages of the N1. Finally, the UR-700 could launch 151 tons of payload versus 97 tons carried by the N1 and 127 tons delivered by the American Saturn-5.

In parallel with the development of the UR-700, Chelomei's engineers drafted a much bigger follow-on vehicle, which would be equipped with nuclear engines. (658) Known as Skhema "A" (Configuration "A") engine would feature the solid core nuclear reactor and enable the UR-700 to deliver as much as 250 tons into the Earth orbit. In a more distance future, a nuclear engine with liquid core reactor known as Skhema "B" (Configuration "B") would be developed, followed by an engine with a gaseous core reactor dubbed Skhema "V" (Configuration "V").
In the end, it lost out to the impressive but poorly built N1, which literally never got off the ground. And that was that for Soviet moonshot hopes.

These days everyone seems focused on getting back to the moon, or even Mars, which is great. Rocket technology has become more efficient and reliable in the decades since Apollo, but the basic physics (fuel, oxidizer, ignition) remain little changed. Because of the relative danger of getting a nuclear rocket into space--even using chemical engines--projects like the UR-700 are not likely to be revived. But it's always fascinating to see what technological solutions smart people come up with to solve problems like this... even if they don't always work out.

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