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Cambridge N-Prize Team To Build Balloon-Assisted Rockets
Rob Goldsmith writes "Earlier this week we heard that Cambridge University Spaceflight would be entering the N-Prize competition. The N-Prize is a competition to stimulate innovation directed towards obtaining cheap access to space. Most importantly, the launch budget must be within £999.99. Cambridge University Spaceflight plan to win the prize using a balloon and a rocket. They have now opened up an official forum where the public can track their progress." The linked story has images from a test flight of July 23, and an interview with a member of the team, Ed Moore.
"Receipts must be produced, if requested, for all items or services purchased which fall within the ã999.99 budget"
http://www.n-prize.com/rules_in_full.html
So if you get a receipt from the fuel you used in the winning flight, it doesn't matter if the price goes up. If however you fail and you need to buy more fuel to try again, then the increase in price would be a problem to you.
I might have answered your question in another post.
One advantage I might imagine is that pulling a rocket up even a few kilometers and launching from there puts you above a large part of the atmosphere. Atmospheric density decreases exponentially height (http://en.wikipedia.org/wiki/Barometric_formula), so for example, at 5 km, the rocket only has to cross half the atmosphere, reducing drag a great deal. Naturally, the rocket must still accelerate above escape velocity (which is not significantly changed at 5 km above sea).
This wouldn't even make too much sense since
with that kind of money a kilogram in orbit would cost around 50000 pound. There are much cheaper means of getting to orbit:
http://www.futron.com/pdf/resource_center/white_papers/FutronLaunchCostWP.pdf
Interestingly small launchers seem to be less efficient than larger ones on average.
Maybe one should just try to hitch a ride.
On the other hand this seems to be a fun project.
I hope they are successful.
Je me souviens.
The idea behind balloon launched rockets has nothing to do with escape velocity/gravity. It has to do with aerodynamic drag. Aerodynamic drag plays a big role in eating up launch fuel at lower altitudes where the atmosphere is dense. A balloon launch bypasses that drag with a low cost, and disposable, balloon filled with hydrogen/helium without having to use expensive/heavy rocket fuel. The concept was developed and first implemented in 1949 and has been done a number of times since for high altitude experimentation and hobbiest projects. Wikipedia has a basic article inder the, somewhat archaic, name "rockoon" (mixture of rocket and balloon).
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By the way, the Federal Reserve is a private corporation....
The Federal reserve is a government institution--your assertions to the contrary are false (and the "World Bankers" drivel is sheerest bullshit). (Cite)
If you haven't been down-modded lately, you aren't trying.
Sacred cows make the best hamburger.
Governments have a tendency to take notice when people build rockets large enough to carry explosives
It was apparently big enough to take pictures, and Governments notice that too.
We are all just people.