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by nakkiel 4139 days ago
I can't warp my head around how quick Vega is to rise (ESA's new light launcher). Here's a video from its qualification flight:

http://www.youtube.com/watch?v=F0IZ6d4wTCg

So far, everything is going well on the mission but I'm very anxious about the reentry of the IXV.
2 comments
morbius 4138 days ago
The smoke plume is characteristic of SRBs, which have a very good thrust-to-mass ration but relatively low specific impulses.

If you've ever seen a Shuttle launch, the long and smoky plume and the rocket "leaping off the pad" will look very familiar.

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jccooper 4138 days ago
It does get going, doesn't it? Vega is a solid-fuel rocket (except for the fourth stage), and those have really high thrust early on.

If it behaves more like a missile than a satellite launcher that's no coincidence: most missiles are also solid-fuel.

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andor 4138 days ago
Most missiles are not designed to carry people ;-)
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jccooper 4138 days ago
Vega isn't designed for people either. It's a small launcher for small satellites--and though its max payload might loft a Mercury capsule, no one is going to build something that small. Moreover, humans aren't well suited to all-solid rockets. They have a rough acceleration profile and poor failure and abort modes.

But that's not rare. Most launchers, liquid or solid or both, aren't designed to carry people. It's easier, for one, because your abort mode can be "blow up and collect the insurance". (Also, they're ultimately derived from ICBMs.)

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