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X-43 Scramjet Rollout
PenguinRadio writes: "The Washington Post is reporting that NASA is readying the X-43 space plane for a 10 second test flight, after which is will plunge into the ocean and not be recovered. The X-43 is an unmanned aircraft (there are three of them) that is used as a testing bed for hypersonic aircraft and may lead to a commercial version in about 20 years or so. Anybody got an extra wet suit?" See also the Reuters article on the same subject, and our previous story about an Australian version.
unmaned aircraft
I should hope the aircraft is unmaned. Putting a big mane on it would seem to serve no purpose other than decoration, and would increase drag a great deal.
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"Outlook not so good." That magic 8-ball knows everything! I'll ask about Exchange Server next.
Great, the Chinese will probally end up with this one too.
Sorry. You're very mistaken.
Air breathing engines have one killer drawback: the air intake. It needs to be very large, which drives up the cross-sectional area of the craft, which drives up the wave drag of the airframe. The air breathing engine has a very low impulse (thrust per unit drag) because its cross-sectional area is huge relative to that of a similar-thrust rocket.
I've said it before, and I'll say it again: Air breathing engines are a bad way to get into orbit. Full stop. The math just doesn't work. It's a pretty idea, but it's impractical with anything like today's technology. We can make MUCH better rockets (aerospike engines have potential) but air-breathers are not the way to go.
And yes, I am a rocket scientist. Thanks for askin'. : )
Why yes, I AM a rocket scientist!
Yes, scramjets are less fuel efficient than a 747 because they accelerate faster to a higher speed.
If you want fuel efficiency, take a slow boat to China. If you want to get to Tokyo quickly or the edge of space, you'll need something that gives a kick in the pants.
Yes, the reason we don't have a real hotel in orbit in 2001 is because space development is moving at the speed of governments. If Pan Am had been flying space shuttles there would be a lot more activity above the atmosphere.
What exactly does everyone think is going to be left of this plane after it slams into the ocean at Mach X?
-- Bird in the Bush: The Renewable Energy Blog http://www.birdinthebush.org
``I wouldn't want to be on the pointy end of one of these things if its got a bomb on it,'' Sitz said. ``We could call someone up and say: 'We're gonna bomb you,' and there would be nothing they could do about it.''
Since this is basically what the US does anyway, it's good to know that we'll have some stability in our foreign policy during the coming decades!
I also find it hilarious that is a NASA project manager talking...
Karma: Bored. (Thinking about resurrecting the "Anyone else is an imposter" joke.)
Sounds like Nasa.
Seriously, the idea is based on the observation that alot of the time you spend going into orbit you are simply coasting. And you are also bringing along alot of oxygen for the fuel. So if you could get your oxygen for the ascent from the atmosphere, and then coast to orbit, you could save a lot of weight. You would still have enough on board for manuevering jets, etc. But this requires something that can operate in the middle range of speeds of Mach 2 to Mach 10 (and higher)
Check out the Vinny the Vampire comic strip
"It is a greater offense to steal men's labor, than their clothes"
I can't beleive that they're not going to recover the jet after it crashes. While I understand that this is a test of the engine only, it seems like there would be a wealth of data to be had from examining the structure of the device, even after it crashed.
While I'm no engineer, don't crash investigators for regular airplanes often look for things as minor as cracks in the substructure to indicate possible areas of improvement for future planes?
I think it's a horrible waste of information and effort to let this thing sink to the bottom of the ocean. Worse, they're putting information in the hands of the other few countries with the resources to salvage this guy, and you can sure bet that they won't share the results with us.
C'mon guys. Fish it out!
The next Slashdot story will be ready soon, but subscribers can beat the rush and slashdot the links early!
Isn't there a very limited market of people who want to plunge into the ocean at Mach 5?
Should have no problem getting venture capital, though.
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Yes, the nick is flamebait
I'll bite:
"A space plane like the space shuttle costs the same amount of money in terms of fuel as a jumbo jet from London to New York does."
How do you figure that? Mile-per-mile? Did you not notice the external fuel tank needed to get the Shuttle to orbit? Do you think LOX and LH are so much less expensive than jet fuel? The External Tank alone uses 526,000 gallons of fuel in the 8.5 minutes before it's jettisoned (That's 1031 gallons per second (g/s). A 747 on the other hand, has a maximum fuel capacity of 57,285 gallons, which it sips at 1.06 g/s.
Jet fuel currently costs about 77 cents/gallon, while LH costs about 75 cents and LOX costs about 35 cents, but that kind of logic is like saying it would be more economically efficient to walk to the moon.
"Wall Street would be the new mission control, and you can bet that the analysts of that city would make space trave as cheap as boarding a jumbo jet - there is no reason why it should not be."
I'd suggest you take a look at this economic analysis of the $/lb costs for the Space Shuttle under various scenarios, including daily launches. It'll never get beneath $640/lb, which is significantly more expensive than boarding a jumbo jet, unless you're a mouse. but then, mice fly free...
It would be more accurate to say that Wall Street would be able to raise enough money in an IPO to send the company's founders into space, but Wall Street itself doesn't have as much to do with the creation of economical solutions as they do the speculation of profitability of said systems.
Kevin Fox
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Kevin Fox
I hear they're moving the 'Taco Bell' sign
that MIR missed into the area where this
is supposed to land. If it hits it, everyone
at NASA gets a free Chalupa....
Check out these cool photos!
I'd like one in my bathroom =)
Any technology distinguishable from magic, is insufficiently advanced.
See also the Reuters article on the same subject, and our previous story about an Australian version.
Or, see the exact same previous story from the last week.
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Never underestimate the bandwidth of a 747 filled with CD-ROMs.
I hate to play devil's advocate on this, but you stated that 'Scramjets are wasteful, and in the wrong direction' then.. do not go anywhere near that topic in the body of your message. Any particular reason you made this omission?
As for the government retarding space exploration, of course they have. You see how corperations act on planet Earth, right? Imagine that up in space, where things like a misplaced bolt traveling at orbital speeds can take out satellites. NASA tends to be very exacting about how and when they do things. Corperations go for the bottom line. Does it make them profit? If so, they don't care about the little details like debris. Can you imagine the difficulty we'd face in even getting out of the atmosphere if our entire LEO sphere was a mass of garbage and debris left from satallite leavings? (well, at least til they managed to drift back to the atmosphere)
I've been following this project for years since I heard it announced. While I'm not the utmost on what they're current plans are, there are reasons for doing things this way. The more disposable pieces they take to orbit (fuel tanks on the shuttle), the more explosive bolts they fire, the more garbage there is. If they can make a SSTO craft (Single Stage to Orbit for those that need it explained), then they cut down on the ammount of crap left in space.
Problem number one is getting the speed involved to reach orbit without booster rockets. Scramjets are the answer to this. They operate at high speeds only (well into the Mach range) and are ideal for use in situations where you don't need the compression of turbo fan blades in other jet engines. Read: A Scramjet is a ramjet only for use at higher speeds.
Problem number two is that, if they really want to make a SSTO craft, they have to carry Everything they need within that craft, all fuel to break escape velocity, everything. The current shuttles carry just enough fuel for maneuvering in space, and dropping back to earth. They do not and cannot (without external fuel tanks) have the reserves within to break out of the atmosphere. The only reason why this new space plane will be able to do it is because it will carry only half it's fuel. The other half (the bulk of the oxygen needed) will be gathered from the atmosphere itself as it flies.
Now, saying this is wasteful is frankly trolling and misinformation unless you can prove that it is wasteful. This plane will be lighter than it must be if it were to burn LOX and Liquid Hydrogen, and will therefor require less power to get the speed necessary to reach orbit. How is this more wasteful than before? What other methods would you use to get to space? A space elevator? Linear accelerator based on the ground? (Check out your Sci Fi book stores for what I mean by these). These ideas are nice and far more efficient, but are a little out of our league at the moment.
Until we can manage to build some of these things and overcome the technical hurdles involved in their creation and use, we still have to use rockets and jets to reach orbit. I'm all for a SSTO craft. They are more cost effective, they are more easily maintanable (The shuttle takes months on the ground for refits of lost tiles, damage from orbital debris, and other maintenance). If they can do this right, they can make this space plane more usefull by making it able to fly more often. Get a small fleet of them, and you could have daily flights to orbit. Tourism anyone?
Oh, and as for why NASA only bought 6 shuttles, several month downtimes, and single missions to orbit. At the moment, I doubt you'll see several shuttles in orbit at the same time. With all the monitoring tools they have, I don't think Nasa has the manpower to handle 2 or 3 in orbit at once. With those factors in mind, and a price tag in the billions (IIRC), they don't need more, they can't handle more, they're certainly not going to spend that much money on something they can't utilize effectively. Would you?
My prediction: the scramjet will successfully accelerate to Mach 5, plowing into a Chinese observation plane and obliterating it. The flaming wreckage will fall from the sky and land on a Japanese pleasure cruiser, sinking it.
George Bush will blame the Russians.