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1

the video show that the principle of helicopter works in a zero-g (no gravity) environnement, not that the principle works in space. The helicopter is able to lift on earth (and int the space shuttle) because of the viscosity of the air. Whitout any friction, there is no move. In space, there is really few particles. So the friction would be very low and ...


2

The thrust coming from a rocket engine is exerted on the engine bell, and it is directed along its axis of symmetry. It's not completely clear how you're modelling your ship but it is probably more realistic to apply the force to the "thruster fire" block, whatever that is. It's important to note, though, that if applying the force to the engine bell and ...


3

Cosmic Velocity has nothing to do with infinity. A cosmic velocity is the minimum speed directed in the necessary direction to escape the gravitational attraction of a cosmic body such as a planet, a star, or a galaxy. Here is a paper which a student wrote about the four cosmic velocities. I don't know if his exact classifications are in common usage, but ...


0

It sounds like what you're looking for in general is an SSTO (Single Stage To Orbit -- http://en.wikipedia.org/wiki/Single-stage-to-orbit -- meaning it doesn't drop off boosters on the way up) rocket with a high payload fraction ( http://en.wikipedia.org/wiki/Payload_fraction -- meaning most of the spacecraft isn't fuel and fuel tank). Unfortunately, ...


1

The answer based on accepted physics is trivial: none. That's why they call it science FICTION. One can theoretically reduce the amount of propellant, but then the required power these ships would have to develop would go trough the roof. Keep in mind that a medium sized rocket develops on the order of 10GW of power for a few minutes during first stage burn ...


2

I'm sure this is an incomplete answer, and would only add to those already excellent, more knowledgeable answers, but I do know that rocket scientists try to situate their launch site as close to the equator as they can, so the Earth's diameter gives some extra "throw" as compared to higher latitudes. I expect when the rocket tilts toward the horizontal, it ...


0

It's not efficient that way. There is something called gravity turn. You need sideways velocity to stay in orbit and gravity turn essentially assists the rocket to turn sideways.


30

I highly recommend you download Kerbal Space Program and see for yourself (there's a free demo version)! Typically the goal of a satellite is to orbit, and thus as the other answers address, you must build significant horizontal velocity. Indeed if the Earth didn't have an atmosphere, you could orbit a few km above the surface, so the main goal is building ...


69

It sounds like you are imagining that what satellites do is go up through the atmosphere, break though into outer space, and hang there. That is not right. If you simply go straight up to outer space (say 300 km above Earth's surface), gravity will pull you right back down, even if you've left the atmosphere, and you'll crash back into the Earth. Gravity is ...


4

Rockets take the shortest path to reach their orbit. If all we want to do is pop up to LEO and come back down again, then we do go straight up. See the first two Mercury missions for an example - they landed north of Nassau. If you want to end up in orbit, you need substantial horizontal speed. Turning at right angles is the least fuel-efficient way to do ...



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