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SpaceShipOne Back in Action
JoeSilva writes "After a 3 month wait,
Scaled Composites' SpaceShipOne is
back in the skies above Mojave! Not only is it patched up from a failed landing gear, it's got a 'thermal protection system' installed.
Looks like high temp insulation on the leading edges. Also they have a picture of it with 'the rocket motor for the flight 13p'. This was the 12th SpaceShipOne flight."
So does that mean that SpaceShipOne will be making a run for the money soon?
They have a "falling bathtub mode".
Wonder how much they could make selling rides on that thing.
--Phillip
Can you say BIRTH TAX
so what happened to flights 9 through 11? The flight log jumps from flight 8 (first powered) to this latest one.
WOOHOO!!!
Check out the test updates here.
AFAIK, these guys are the closest to winning the X-Prize- go team!!!
Any generalization is a stupid one.
A great set of photos (hopefully soon to be mirrored) is available here.
Looks like the flight was a few days ago (March 11) - why is this the first report? They're being very quiet about this. And how did Joe Silva track this down?
Energy: time to change the picture.
The X Prize is NOT ABOUT LEO! It's about reaching 100KM, with at least 1 person, in a vehicle capable of carring 3, twice in 2 weeks.
Generally, bash is superior to python in those environments where python is not installed.
While you are there check out the Global Flyer It is just as cool in my book. The similarity in the designs of the craft are interesting. The idea of flying around the world on one tank of gas is pretty wild.
It's hard to believe that's how Micronians are made. Why don't we see it right now by having you both kiss one another?
I've been following the X-Prize work at Armadillo for the last year or so. If nothing else than for the John Carmack factor. They seem to have stalled lately, always reengineering their rocket motors and such. I'm still cheering them on anyway though I can't see them surpassing Scaled Composites at this point.
One bad monkey spoils the whole barrel.
Of course, the project we have to compare it to is John Carmack's Armadillo Aerospace venture (since they have the decency to provide week-by-week status reports, which I consider manditory Monday reading). The folks at Armadillo are still working on getting their engines to light reliably (extra important since they're using five of them) and still haven't had anything like a successful test flight.
I dunno, man -- If I'm Carmack, I'm thinking it's time to really get at it if you're still serious about winning the X-prize. The SpaceShipOne folks seem to be putting them further and further into the rear-view. Which isn't to say they *can't* catch up; if the Armadillo team can get their engines lighting reliably, they should be about ready to bolt the thing together and start flying.
Man, this beats the heck out of money pits like the ISS, eh? Nothing like a little old fashioned get-the-prize competition to turn up some interesting stuff. Maybe a $100 billion prize for the first company to land people on Mars and bring them back ought to be next -- get the government to cooperate with permits and NASA to share their tech. I'd bet you'd see people there inside a decade.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
now with link and without the added space
i know, i suck at slashdot
Also, IMHO the ship looks like some high-school science project with way to much duct-tape with the leading edges done the way they have it.
I think that the work being done by Scaled Composites will prove very useful in the next few years. Where I thank we need to see a much greater effort is in the fuels to drive these kind of vehicles. With advances in physical chemistry we could see an improvement of 2 or 3 orders of magnitude. With those kind of fuels one could put a bottle rocket into orbit!
"Can there be a Klein bottle that is an efficient and effective beer pitcher?"
Apparently, Scaled Composites is one of two teams to have applied for a permit from the FAA to launch a spaceflight. The other is Armadillo Aerospace, run by John Carmack of Doom fame. It's interesting to compare and contrast the two companies. Rutan has a sleek ship with lots of cool round windows that launches from a funky big plane, and they have some good solid live testing. The Armadillo team's site really shows you the nitty-gritty of building something that flies in your spare time, with pictures of them welding engines together, making a crew capsule out of whatever they could find, and building a landing gear with some thick cable springs. I'm guessing that Rutan will win, but I'll hold out hope that the garage engineer can pull off at least some type of flight to give courage to that old entrepreneurial spirit....
I'm waiting for Carmack to respond to the space race. I'm also waiting for a release date for DooM3! :)
I am defenseless. Use your button. Mod me down with all of your hatred.
They better not have any more delays like that last one, if they want to win the X-Prize. The $10 million dollar prize expires at the end of this year, and a lot of other groups are competing for it.
I think we'll see some exciting new developments in space technology over the next few years. I'm confident someone will win the X-Prize,(which is more a PR bonus for starting a space tourism company than anything else) the Bush Admin wants to send folks to the moon or Mars (probably using nuclear propulsion), and it's all but a foregone conclusion that someone will try to build a Space Elevator soon.
The kinetic energy required to accelerate a gallon of gasoline to orbital speed is more than the chemical energy contained in the gasoline.
By contrast, "merely" lifting something up 100km doesn't require much energy at all.
So, er, no, leading-edge heat shields ought to be just fine. Fiberglass or carbon-fiber composites might even survive a flight or two without any shielding at all.
Rutan and Scaled are prob the Ultimate Gargage Engineers. He's done stuff that "experts" called impossible for years.
/.ed)
The "early" kit planes he designed are still works of "art".
(bad news, the site is
For the good of the community :)
[...]
Results:
Slashdot's editors are facists.
Launch conditions were 48,500 feet and 125 knots. All systems performed as expected and the vehicle landed successfully while demonstrating the maximum cross wind landing capability.
If it's for the good of the community, then don't put in your personal opinion in the middle of the post.
There may have been more random crap in there, this was the first one I saw. Feel free to remod the karma whore appropriately.
It is soooooo Buck Rogers-esque!! Not the late 70's/early 80's TV show Buck Rogers, I mean the 1930's - 1940's Buck Rogers.
We were somewhere around Barstow on the edge of the desert when the drugs began to take hold. - HST
Either some moderators were sleeping, or else they agree with the assertion.
It's probably a bit of both, if you ask me.
The energy content of gasoline is about 42e6 J/kg.
Orbital velocity (at the surface of the earth) is about 8000 m/s. Kinetic energy of 1 kg at 8000 m/s is 32e6 J. (That is, you need about 32 MJ/kg)
However for those who want the whole story, the parent to this is correct: to get all that energy out of the kg of gasoline, you *also* need about 2.8 kg oxygen. Gasoline-oxygen gets you about 11 MJ/kg, which is about a third of what you need to hit orbital velocity.
To get to 100 km altitude, you need only 0.96 MJ/kg, which is no problem for gasoline-oxygen.
"There are a dozen opinions on a matter until you know the truth. Then there is only one." - CS Lewis (paraprhase)
Nuclear reactions yield about a million times more energy per unit mass than do chemical reactions, so it's natural to try to get the energy that way.
NERVA got OK Isp (about a factor of 2 better than chemical rockets, something like 1000 seconds), but its thrust-to-weight ratio was pretty low, about 4 if I remember right. That's because it included a critical, operating nuclear reactor with an actively controlled chain reaction, and them thar things are heavy.
Thrust-to-weight is just as important as Isp to a rocket: higher thrust-to-weight means you can tote more fuel, payload, and structure for the same Isp, since you always have to have the mass of the engine itself around. By contrast to the NERVA's thrust-to-weight of about 4, the Space Shuttle main engines have a thrust-to-weight ratio of around 75. Since solid rockets are technically made out of their own fuel, their effective weight is much lower for this calculation (pretty much just the bell nozzle) and you might see numbers in the several-hundreds range.
Of course, one could always work on making the NERVA more lightweight -- but do you really want to optimize a nuclear reactor for mass, rather than safety? I didn't think so.
Now, for use in space, thrust-to-weight isn't so important. The rocket doesn't have to support itself against gravity, so low-mass engines that also produce low thrust are perfectly OK.
Of course, international treaty bans the use of critical nuclear reactors in space, but that alone wouldn't slow down our current administration very much.
[Nuclear reactors get flown into space all the time, but they always have much less than critical mass, relying on spontaneous decay to keep the chain reaction limping along at a constant rate. NERVA would require controlled reaction rates, hence a critical-mass reactor.]
The ship only has to have accomodations for three people. The rules allow for substituting ballast for the passenger's weight and letting the single pilot go up alone. The relevant rule is
How do you know how what sort of cooling mechanism is in place or how effective the heat shield will be? Just looking at pictures? For all you know there could be some elaborate fluid cooling system internally distributed, making blunt edges less necessary. Or that heat shield could be more effective than what your extensive calculations and research indicate.
My point is is that you shouldn't be so quick to judge. Or maybe you're just shoehorning some semi-related facts in an insightful-sounding post to raise your karma.
(btw I am an aeronautical engineering major)
Shotgun!!!!!!
I don't have every answer, but here are a few facts:
...
You've got it right on the heat dissipation, though I mentioned that more to address comments that all the heat would be "taken" along the leading edges of the wings, which isn't the case even though they do tend to get pretty hot - which you can see in infrared pictures of the Shuttle as it descends.
This isn't an orbital vehicle, no. A flight will take around half an hour and it'll reach an altitude of 100km or so - across the official space boundary, but it won't stay there long. A lot more fuel would be required to reach orbital velocity, and a lot more heat shielding to make it back.
Re-entry profiles are usually "corridors" only a few degrees wide; come in too shallow, and you skip off the atmosphere; too steep, and you're crushed by G forces. The exact profile differs from design to design, I'd imagine.
Most of the envelope is determined by fuel and the shape of your ship. Amazing things can be done by designing your vehicle well and taking advantage of physics... take a look at the Sanger skip bomber", a suborbital craft designed to fly once around the world and make an unpowered glide landing, "skipping" off the atmosphere like a stone off water.
Notice how flat the underside of the spacecraft is
i am a soviet space shuttle
I wouldn't trust any Thermal Protection System until all the employees have submitted their TPS reports in triplicate.
This account verified sig-free since..., uh, never mind.
If you don't believe me, look at the x-15 x-15 in full ablative coatings. The pilots wouldn't fly it unless they put a painted on top of it...
You forgot to include the potential energy required to get from earth's surface to orbit.
For LEO (200 km), circular orbit velocity is 7789 m/s. KE is 30.3 MJ. PE for 200 km altitude (from earth's surface to orbit) is 60.7 MJ. If you launch at the equator, prograde, then you gain 464 m/s, for an intial KE of 0.1 MJ.
So total energy required to transport 1 kg to 200 km LEO from stationary at earth's equator, is 90.9 MJ.
Of course, if you're burning the fuel along the way the energy requirement drops as mass decreases, and you also have to add in oxidizer mass, but I don't know the equations for that.
The rocket engine has been tested on the ground at full power for an entire burn. The boost phase on the previous flight was stopped to keep the test program progressing in incremental stages. Binnie could have just as easily kept going well past 100 km, but they're still wringing out the subsystems. The rocket engine works. It's a very clever and simple system that uses nitrous oxide as the oxidizer and rubber as the fuel. The rocket can be throttled by changing the flow rate of the liquid oxidizer. A low cost, safe and throttleable solid rocket booster is quite an achievement (but not invented at Scaled).
To correct a couple of falacies in previous posts.... 100 km is the internationaly recognized limit for being an astronaut. Parabolic suborbital flights do not require heat shielding because they are much slower than orbital flights, not because they have less atmosphere to penetrate on reentry. Both are essentially in the vacuum of space.
I like the Armadillo Aerospace research too, but it isn't going to win the X-Prize. I think they should have called their rocket engine the BFR-9000.
And to the person who said the older Rutan aircraft designs are works of art, I'd have to agree. A picture of my Long-EZ is here.
The X-Prize is going to change the way we look at space. No longer will a $1B shuttle launch be required. We will all have access to space. This is long over due. My appreciation to those who are making it happen. As always, all that is required is big dreams, intelligence and determination.
>> My ultraviolent Linux switch video.
That's a strange thing to call Death Valley.
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