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Real Engineering always does such an amazing job on all their content, although I can't help but fixate on what the release mechanism looks like since it wasn't

Real Engineering always does such an amazing job on all their content, although I can't help but fixate on what the release mechanism looks like since it wasn't revealed in this video. This comment was inspired by another commenter saying something about shooting the rocket off the side of a mountain. I'm theory-crafting here without any specialized knowledge on the subject, asking strictly out of a mix of curiosity and fun. Is there an online community where I could pose this question and get a well-informed response about its viability? What if you dug a very deep hole, created a near-vaccuum, and you shot the rocket out like a rail-cannon? Here's a quick and simple sketch [0] of what I have in mind. [0] https://imgur.com/bmHiMdq https://imgur.com/bmHiMdq

throwoutway 4y ago
How do you produce a near vacuum with a hole on one end?
- picsao 4y ago
- tripa 4y ago
  By extending the cannon's end to space.
  - tgarv 4y ago
    Oh no, now the vacuum of space is leaking into the base of a mountain!
    - Smoosh 4y ago
      What if it leaks out to sea level and kills us all?
- TheAceOfHearts 4y ago
  Can't you do something similar to what the engineers in the rocket throwing video are doing?
- adgjlsfhk1 4y ago
  A door.
- jandrese 4y ago
  Presumably with a rapidly opening door. Of course now you have to design your rocket to slam into an atmosphere at launch velocity. You might have to install enormous compressed air tanks at the end to pre-accelerate the air right as the door opens just to make it less like hitting a brick wall of onrushing air.
mLuby 4y ago
> What if you dug a very deep hole, created a near-vaccuum, and you shot the rocket out like a rail-cannon? What would happen is your payload would follow a ballistic trajectory up through the atmosphere into space, then it'd fall back down and hit the ground somewhere west of the hole because earth rotated under it while it was in flight. As XKCD puts it, "The reason it's hard to get to orbit isn't that space is high up. It's hard to get to orbit because you have to go so fast." https://what-if.xkcd.com/58/ https://what-if.xkcd.com/58/ Also the way 2-body orbits work, you will always return to the point you last changed your velocity. That means your hole-launched spacecraft's flight path is actually an elliptical orbit that's so extremely narrow that it looks more like a straight line up and down, and then the ground prevents the vehicle from continuing on its orbit around the Earth's center of mass. So if you want to "circularize your orbit" you have to increase your sideways velocity by thrusting at the top of your orbit, so you can as Hitchhiker's Guide puts it "throw yourself at the ground and miss." That way the ellipse is mostly a circle around the Earth and you'll return to that thrust point in space rather than returning to hole's entrance. So you'd want to make the hole more like a train track running just under the surface (or an evacuated tube just above the surface). That's sort of what SpinLaunch and other non-rocket space launch systems like mass drivers and Project Babylon.

throwoutway 4y ago

How do you produce a near vacuum with a hole on one end?

picsao 4y ago
tripa 4y ago
By extending the cannon's end to space.
- tgarv 4y ago
  Oh no, now the vacuum of space is leaking into the base of a mountain!
  - Smoosh 4y ago
    What if it leaks out to sea level and kills us all?
TheAceOfHearts 4y ago
Can't you do something similar to what the engineers in the rocket throwing video are doing?
adgjlsfhk1 4y ago
A door.
jandrese 4y ago
Presumably with a rapidly opening door. Of course now you have to design your rocket to slam into an atmosphere at launch velocity. You might have to install enormous compressed air tanks at the end to pre-accelerate the air right as the door opens just to make it less like hitting a brick wall of onrushing air.

mLuby 4y ago

> What if you dug a very deep hole, created a near-vaccuum, and you shot the rocket out like a rail-cannon? What would happen is your payload would follow a ballistic trajectory up through the atmosphere into space, then it'd fall back down and hit the ground somewhere west of the hole because earth rotated under it while it was in flight. As XKCD puts it, "The reason it's hard to get to orbit isn't that space is high up. It's hard to get to orbit because you have to go so fast." https://what-if.xkcd.com/58/ https://what-if.xkcd.com/58/ Also the way 2-body orbits work, you will always return to the point you last changed your velocity. That means your hole-launched spacecraft's flight path is actually an elliptical orbit that's so extremely narrow that it looks more like a straight line up and down, and then the ground prevents the vehicle from continuing on its orbit around the Earth's center of mass. So if you want to "circularize your orbit" you have to increase your sideways velocity by thrusting at the top of your orbit, so you can as Hitchhiker's Guide puts it "throw yourself at the ground and miss." That way the ellipse is mostly a circle around the Earth and you'll return to that thrust point in space rather than returning to hole's entrance. So you'd want to make the hole more like a train track running just under the surface (or an evacuated tube just above the surface). That's sort of what SpinLaunch and other non-rocket space launch systems like mass drivers and Project Babylon.