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Air Force Spaceplane Readying For Launch
FleaPlus writes "The US Air Force is currently preparing for the launch of the secretive X-37B OTV-1 (Orbital Test Vehicle 1) spaceplane, which was transferred from NASA to DARPA back in 2004 when NASA opted to focus its budget on lunar exploration. The reusable unmanned spaceplane is set to launch in April on top of a commercial Atlas V rocket, orbit for up to 270 days while testing a number of new technologies, reenter the atmosphere, then land on auto-pilot in California."
How secretive can it be if the launch is posted on /.?
Yes, but closer to what? The existence of this project seems to demonstrate that a lot of people didn't learn anything from the Space Shuttle. Wings on a space cargo mover add a lot of unnecessary weight that people should have concluded is more detrimental than useful. The space industry has ways to launch objects without big, heavy wings and even without a crew. The ability to use the large cargo bay to return large objects to the ground isn't that important, I can only find one example of it happening, the LDEF.
There's a lot of unpleasant stuff you can put in there. My guess is "rods from god", that is, a payload of tungsten or depleted uranium rods that you can drop on a target. If you can get a rod to hit with it's orbital velocity (8 km/s), that would be roughly 7 kilotons (TNT) of energy per kilogram of rod. Halving the velocity of impact (which to me seems achievable and more viable than my first number) would still result in almost 2 kilotons of energy per kg of rod. My view is that this would be more effective than a few nuclear bombs (perhaps the most unpleasant payload you can put in there) since you aren't restricted (ok, less restricted since there's at least one treaty (Outer Space Treaty?)that prohibits any weaponization of space) by treaty, you don't cross an arms-race threshold, and you get similar delivery energies.
They also can have more flexibility to launch recon and spy technology. Maybe they're looking at retrieving satellites in order to get more data out of them. Remember physically moving data is still the fastest way to move data. You are restricted in how much data you can transfer from space to ground via radio. Maybe they're planning satellites that can generate petabytes or more of data (1,000 terabytes) and return it to Earth. For example, multispectral scans of the Earth at 1 meter resolution. A single byte of information per square meter would be roughly 150 terabytes of data. A single byte of information per 10 cm (decimeter) square would be 15 petabytes of information.
The vehicle could act as a spy satellite (it could beam some of them down in real time) while archiving everything it sees. The DoD gets both a 270 day satellite with latest technology and a massive, comprehensive archive which it can dig through at its leisure.
Wings on a space cargo mover add a lot of unnecessary weight that people should have concluded is more detrimental than useful. The space industry has ways to launch objects without big, heavy wings and even without a crew.
Oh, they've got plenty of ways to launch stuff without those big ole wings.
Amusingly, you're missing that the only possible use for wings on a re-entry vehicle is military...
The shuttle had them for two military reasons. The USAF kicked in a bunch of cash, or at least promised to, in exchange for:
1) Massive LANDING capacity. Grab that low earth orbit USSR spy satellite and examine it at your leisure. The USSR response is of course high earth orbit, making them less effective, and wasting satellite mass on things like self destruct systems. Much like nuclear weapons, the plan was never to actually use it, but to manipulate the other side's behavior... Why the USAR wanted the USSR out of low earth orbit in the 70s is a mystery to me. Maybe discourage orbital bombardment or space based ground attack lasers or something.
2) Abort once around and very strange orbit and reentry profiles. So you launch, do whatever cloak and dagger stuff you want, then you want to immediately land, like "NOW". Meanwhile the earth rotates underneath you. So put big old wings on to glide. So what if the L/D ratio averages only 3:1 if you start 200 miles up, that's 600 miles crossrange. Since the shuttle program promised everything to everyone, I'm sure a shuttle-class runway is accessible every 1200 miles or so, at least with a lot of imagination and creative hot-dog piloting. Also, if the Bulgarians threaten to shoot down any military overflight spacecraft, you can simply pick a bizarre orbit to avoid them, with a bizarre reentry requiring some gliding around. The ability to land anywhere at any time somewhat limits their ability to screw around with us, including watching our vehicles with their telescopes. Extra glide range adds a lot of capability to military flight plans. Civilians, of course, would simply wait and deorbit at a better time/place, but the military "needs" more capability.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
While it is nice that this will give the Air Force a means of getting an expensive payload up into orbit and back down again quickly and safely (like onto a runway as opposed to a parachute landing on the ground or at sea) it really doesn't help the overall problem of making access to LEO significantly cheaper. Remember when you're in LEO, you're halfway to anywhere (I forget who said that quote but from the viewpoint of orbital energistics it is true).
Now that the Obama administration has (hopefully) set us on the right course by FIRST developing the technologies to get us into space, THEN trying to get somewhere, now maybe would be a time to revisit some abandoned ideas. Like the X-34 (I think it was called "Venture Star") using a deltoid lifting body with an aerospike engine it promised to make SSTO (Single Stage to Orbit) possible. Or the "Delta Clipper" a vertical takeoff and vertical landing rocket, I think they got to 1/4 scale.
While I don't know if the "Delta Clipper" was fatally flawed (I think one of its landing struts collapsed), I heard that the problem with the "Venture Star" was they simply couldn't make the (then) state of the art composite fuel tanks work. So has material science improved enough to make it feasible? Or do we have to wait until "magic" carbon nano-tubes can make eggshells seem like horribly efficient containers?
An Air Force General once said: "A new plane doesn't make a new engine possible, a new engine makes a new plane possible." That's why the aerospike engine had such promise because it automatically adapted to the changing surrounding air pressure to keep the "nozzle" shape efficient. That (with new and improved) fuel tanks, just might make SSTO possible which, aside from space elevators or air breathing hypersonic space planes, is the only way we'll REALLY bring down the cost of getting into orbit.
The shuttle's promised capability of "bringing cargo back" is a bygone requirement of the days when retrieving a spy satellite was needed to recover the film. How many payloads did the shuttle actually BRING BACK, compared to how many times did it come back with an essentially empty cargo bay, thus purely wasting the space?
I doubt that you personally inspected the cargo hold after each classified military shuttle mission. Anyway, the wikipedia page you're looking for is:
http://en.wikipedia.org/wiki/Deterrence_theory
The situation would imply that, at least in low earth orbit, the USSR was violating some earth orbit treaty, or was planning to do so, and we knew it via some "special means" but needed a public way to wave a geiger counter nearby their satellite to prove it. That, or, we just wanted to shooo them out of low earth orbit.
A lack of USSR spy satellite launches into low orbit during the shuttle program, is just possibly, a side effect of the existence of the shuttle, not just some random unfortunate unexplainable quantum fluctuation that unfortunately made the shuttle useless, like you seem to imply.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
You have it backwards. The USAF X-20 Dyna-Soar and X-15 programs were well underway until Gemini and Apollo came along and took all the funding and personnel. Now 50 years later they're trying to complete what the X-20 program started.
The X-15 program spent 2.5 billion and made 199 flights.
The X-20 program spent 1.5 billion before it was canceled.
Apollo cost 22.5 billion.
Note that NASA used much of the data gathered from these two programs and as such did not have to incur those costs.
Spoken like a true idiot. Of course you can do it at 1MPH, however you still need to maintain a force to counteract gravity. At 1MPH, you will be spending a literal shit ton of fuel just to maintain that 1MPH speed, spend more fuel, go faster, win.
Also, you do need a certain velocity to escape Earth's gravity, if you managed to somehow get into Low Earth Orbit at 1MPH you would simply fall like a stone back into the Earth. If you achieve escape velocity however, you can maintain an orbit around the planet.
Something tells me you're not an aerospace engineer.
The existence of this project seems to demonstrate that a lot of people didn't learn anything from the Space Shuttle.
The problem with the Shuttle was not that it had wings. The problem with the Shuttle was that it was designed (and redesigned, and redesigned ...) to be all things to all people. I guarantee you, if the Saturn V had been built the way the Shuttle was, it would have cost ten times as nuch and been lucky to get a tenth of the way to the Moon.
The lesson to be learned from the Shuttle is not "don't build spaceplanes," but rather "don't try to build one single vehicle for every mission that NASA, the Air Force, commercial operators, and my cousin's dog might possibly want to perform in space."
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
If you check out the photos on Wikipedia of X-37B underneath the Rutan lift vehicle, you can see what looks like a flagpole sticking out of the nose. This spike is retracted at launch and extended prior to re-entry. The purpose of the spike is to create the leading sonic boom (hypersonic bow wave) and transonic region during re-entry -- well in front of the vehicle itself. The atmosphere reaching the wings and thermal protection surfaces is much slower than the hypersonic bow wave -- thus less heating occurs on the fuselage than on the spike.
The retractable/extensible spike absorbs such an enormous amount of energy and transforms it into heat, yet the spike is not very massive. In order to dissipate the heat without transferring it to the fuselage or melting in an uncontrolled manner, the spike is designed to ablate like many heat shields have (e.g. Apollo). "Ablate" means that the spike flakes apart in a controlled manner which leaves behind useful which continues to be the interface between the craft and the hypersonic flow.
The spike is shown extended in the re-entry test photo because the vehicle was configured for re-entry.
Before GWB scuttled Al Gore's X-38 ISS re-entry vehicle, there had been some talk of incorporating the ablative re-entry spike into ISS return craft. It appeared from the outside (I'm not an insider) that the military community in the US was getting paranoid that revealing the secret ablative spike technology to the foreign competition.