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I think they were suggesting that you could save fuel for once you're out of atmosphere, so that you're not fighting air resistance when you start a burn to get
by Zelizz 7y ago
I think they were suggesting that you could save fuel for once you're out of atmosphere, so that you're not fighting air resistance when you start a burn to get into orbit.
- mikeash 7y agoYou could save a decent chunk of your fuel this way. Maybe 25% or so. In exchange for that, you have to build your rocket and satellite to withstand 10,000 gees of acceleration and hypersonic flight through the lower atmosphere. And somehow build a rail gun that can fire something the size of an office building.
- aeneasmackenzie 7y agoYou use an extremely long track, not high acceleration.
- mikeash 7y agoHard to do if you’re aiming straight up.
- CapricornNoble 7y agoYou'd have to re-purpose something like a deep mining shaft from a diamond mine, then stick a giant rail gun in it, almost like Germany's V-3 cannon[1] but on steroids. [1]https://en.wikipedia.org/wiki/V-3_cannon https://en.wikipedia.org/wiki/V-3_cannon
- imtringued 7y agoNo we aren't aiming straight up because we need to get into orbit. We need to go sideways as fast as possible. As long as you're not aiming at the ground you will always aim "up" but not straight up.
- mikeash 7y ago“Imagine putting one or many of those new Space X internet satellites into a rail gun that goes straight up.” Firing sideways could save you much more fuel but also means you’re in the lower atmosphere at much higher speed and for much longer.