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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.
The price of fuel hasn't really gone up very much, if at all. What's happened is that the money supply has increased, causing major inflation. The "War on Terror" in Afghanistan and Iraq and federal government bailouts of large banks were financed by "printing" (most of it is electronic actually) money from NOTHING and then spending it, which the Federal Reserve is more than capable of doing (so are other banks; see Fractional Reserve Banking). When you keep doing that with hundreds of billions of dollars, it devalues the currency because there is X amount of wealth represented by Y amount of dollars in circulation. If Y increases while X does not increase or increases more slowly than Y, then each dollar is worth less than it was previously. Yes they are a cartel, yes they control the market by carefully adjusting how much oil they produce, but for the recent oil price hikes we keep hearing about in the media, OPEC is merely adjusting their prices to match the current value of the American dollar.
By the way, the Federal Reserve is a private corporation, which means that allowing them to print money and control our currency is UNCONSTITUTIONAL because only the federal government has this power. They are one part of a worldwide organization known as the World Bankers which controls the currency of almost every "industrialized nation" on the planet. Like most threats we face today, the founding fathers warned us about this one:
"Deprive the people of all property". Sound familiar? How's that mortgage market doing these days?
Basically, if you can create economic crises and social unrest, if you can bankrupt a nation anytime you want, you can take over that country without having to fire a single shot.
I'll admit, I don't know what the N-Prize is and I did not RTFA; I am assuming the goal is to reach some kind of sub-orbital or LEO flight. I've looked in to this for my own balloon projects. The energy savings from using a balloon are only a small percentage of the overall energy required to achieve orbit.
It takes about 20 times the amount of energy to reach LEO than it does to just reach the same altitude. When you compare this energy requirement to the savings of launching from the ceiling height of a weather balloon (40km) it is not much; especially considering you still have to get to the Karman Line (100km) plus the weight of fuel required, which must then be lifted by even larger balloons. Therefore, it's more economical and efficient to burn the fuel as close to ground as possible.
I'm only an armchair rocket scientist though, so I might have this all wrong. In any case, I certainly wish them good luck - Maybe I'll go read the article now.
To mod as Insightful the person who mentions "What if fuel prices increase?" while modding down as "Offtopic" the person who discusses why they have and might increase is contradictory, at best. They are either both offtopic or both insightful. I think sometimes moderators forget that "Offtopic" and "Troll" are not synonymous with "I disagree" and "I don't like what that guy said but I won't try to refute it".
I might have answered your question in another post.
This was a politely worded post. You worded this in a non-inflammatory manner and explained why you feel the way that you do, did not use invectives or name-calling and did not even take a very controversial position, and yet you were still modded as Troll. This is one of the better statements on the recent quality of Slashdot moderation that I've seen in a while. You point out that they were not applying the moderating guidelines and they respond by failing to apply them some more, without ever explaining why they disagree with you because they probably realize they would not have a leg to stand on. I'm fully expecting to get modded to -1 myself for pointing this out, but that's okay. I have karma to burn and I'll feel better for having done it since I believe this sort of bullshit needs to be called out wherever it occurs.
It is a miracle that curiosity survives formal education. - Einstein
You are correct in your energy estimates, but a high altitude balloon launch has other significant advantages:
1. Your rocket engine can be an engine with vacuum geometry meant to work well in space. This differs from an engine meant to operate at low altitude.
2. Your rocket design does not need to include complicated supersonic flight in dense air, so your vehicle can be more optimized for the mission at hand rather than aerodynamic.
don't cut it off www.mgmbill.org
I think the point, if there is one, is they wanted the rockets to have a payload and not just be a cylinder filled with rocket fuel. As for the size, I'm assuming its low to not only make it easier to achieve but to avoid people being accused of making missiles. Governments have a tendency to take notice when people build rockets large enough to carry explosives
The "burn most your fuel close to the ground" only applies to big rockets that are having to use early fuel to get later fuel up to altitude.
In the present case both those assumptions are violated, making their approach more sensible than it sounds. First off, for a big rocket most of the energy required will be used to 1) get up to speed and 2) gain altitude, with 1) being the biggest concern. For a small rocket, both of these will initially be swamped by 3) friction. The higher you are when you start, the less of your fuel you will waste just overcoming drag.
Secondly, the rule only applies when you are gaining the altitude by burning fuel in the first place. When you aren't having to burn fuel to get up there, you'd always come out ahead launching from a balloon (or even a mountain top) provided you could figure out how to make it work. Heck, with a tall enough tower (hint: think GEO) based on the equator, you could launch a satellite by hand!
--MarkusQ
Cost per kilo is somewhat missing the point.
Firstly, you can't buy a kilo to orbit. You simply can't.
You may be able to beg a ride-along if you have the right political connections, but otherwise it's impossible.
Secondly, it's unlikely that if 20g to orbit is $2000, 200g to orbit will be $20000.
Thirdly, and perhaps most importantly.
20g to orbit can't do much. You can put a bad camera, a radio, a solar panel, and a magnetometer on it, and maybe if you push the envelope really hard a 3-axis gyro. (to calculate your orbit)
200g however, even if it was $10000 per flight is in the realm where universities with modest physics, aerospace, or electronics facilities might consider it interesting to put up a small test sat.
Your cellphone weighs under 200g, even if it has GPS, GSM, accellerometers, wifi, camera, ...
With 200g in a small satellite, you've got a good shot at a reasonable camera, stabilisation using the earths magnetic field, GPS, a much better radio, solar panels, batteries to keep it alive during dark.
It's even reasonable that you could have a small part of it - say 50g - as a single-shot rocket able to optimise the trajectory.
I note that http://www.rcgroups.com/forums/showthread.php?t=814157 there are amateur build fully remote controlled planes at under half a gram.