Amazing Rocket Launch Simulation

[smtech]

Hello everyone,

 

I just watched this video of UK rocket launch!? It is said to be launched soon, but is this possible?

 

http://www.youtube.com/watch?v=fEJGI3NjJso

[CaptainPanic]

If the goal is to achieve just high latitude (they say that space starts at 100 km altitude), then the idea of a balloon is quite good, because the rocket launches at 20-30 km, and the balloon shortens the distance by 20-30%.

 

If the goal is to achieve orbit, then the balloon seems utterly pointless, because the goal is to achieve a high velocity, not high altitude.

 

For practical purposes, it also seems the wrong technology. Even the largest airships (zeppelins, for example the LZ 127 Graf Zeppelin) had only a payload capacity of 15000 kg. The Space shuttle has a payload (to low earth orbit) of 24,200 kg... and that's excluding the weight of the vehicle and all the fuel. My point is: there is no balloon large enough to lift a big rocket.

 

I know I sound negative here. However, I think it's a pretty cool project. I think that the real value of such projects is in the fact that we learn to think simple about rocketry again. Everything related to space sounds complicated and expensive... and that's perhaps not strictly necessary.

[ewmon]

The music and scenery was very pretty.

 

I hope they computed the reaction of the platform to the rocket thrust.

 

And the platform serves what purpose (instead of simply hanging the rocket from the balloon)?

[Zolar V]

I am pretty sure the point of the baloon was to achieve an altitude to reduce the amount of propellent needed by the rocket to achieve orbit or outerspace.

 

But what i really cant figure out is why they have the rocket sitting on the platform. why don't they just have it in a sort of hanging configuration. i think less energy would be wasted if they do it that way. I'm not sure.

[CaptainPanic]

I am pretty sure the point of the baloon was to achieve an altitude to reduce the amount of propellent needed by the rocket to achieve orbit or outerspace.

 

Low earth orbitrequires a velocity of about 7,000 m/s, and an altitude of about 200,000 m.

Comparing the kinetic energy and the potential (height) energy, for a theoretical object of 1 kg:

 

Kinetic energy = 0.5*m*v2 = 0.5*1*7000^2 = 24.5 MJ

Potential energy = m*g*h = 1*9.81*200000 = 1.96 MJ

 

In other words: the kinetic energy is more than 10 times more than the potential energy... therefore it's rather pointless to lift that rocket a little higher just to give it that 1% extra energy.

The atmosphere will give the rockets a little more drag (friction)... but if rockets accelerate straight up for the first few kilometers, then this is hardly an issue. But if you can find any articles that suggest that rockets (or the space shuttle) significantly heat up during take off in the atmosphere (not: landing), then I may reconsider my point.