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NASA Tests X-43A
An anonymous reader writes "NASA TV has live coverage of the
launch of the X-43A
scram jet flight. Hopes are that the unmanned vehicle will reach speeds in
excess of mach 7-10. The last flight a few years ago failed." Stephen Watts sends this link for X-43A background information.
and destroy it again because they forgot something
good idea
And, no, I should not have used the goddamn Preview mode first.
Please give us the verbal rundown. I'm on a system without Realmedia.
it all uses the same bandwidth pool right?
And probably irrelevent, since there's no funding for future tests.
Ah, but if it is successful, they may direct more funding towards this kind of research. Even if it isn't successful, they might learn enough to still warrant putting in more funding.
WWJD.... for a Klondike bar?
They should have launched 2. One with the camera and one doing the test.
I'm pretty sure they only had one remaining test vehicle. Also, why waste money sending two (one with a camera) when you're not even sure one would even be successful? Also, at that high of speeds, and all that, video might not be the best information gathering tool.
WWJD.... for a Klondike bar?
You are wrong.
A supersonic combusting ramjet is way way way incredibly more technically challenging than a regular ramjet.
Managing the shock wave systems to provide adequate fuel mixing and ignition is only barely possible today with the biggest computer simulations on the planet.
I don't know what you consider "revolutionary", but sustained supersonic combustion is a Really Big Deal.
Why yes, I AM a rocket scientist!
..would be mindbuggeringly fast. Imagine you're standing in the middle of the Bonneville Salt Flats on a day with perfect visibility in all directions:
The X-43A would cross from (visible) horizon to horizon in about 10 seconds.
Your ASF video feed runs anywhere from 8 to 30 frames per second (lets assume 30 fps, broadcast standard). Mach 7 is 2.382 km/s, and Mach 10 is 3.403 km/s (lets assume it's a marginally successful test at Mach 7). A little algebra and you've got 71.46 km per frame, or 44.4 miles per frame.
Where am I going with this? 44 miles per frame is a pretty good clip. It really makes me wonder (when you watch the clip) that any person could recognize enough land marks over the flight path for the images to have any impact, especially given how compressed the images would be. I just found that in the clear air of the midwest USA, the average visibility is 140 miles. So, in 3 frames (1/10 of a second), you've covered the farthest landscape a person would normally be familiar with.
Suppose you want a 2nd live feed... How are you going to transmit the data out of the plane? I'm pretty sure that nothing ground based can do it, so you need a satellite or something to receive the broadcast, but then you have to worry about targeting. With that much trouble, you might as well keep the recorded data on board and download it after the flight. In which case, you'd still only need one feed on the website.
with a scramjet you no longer need several million lbs of liquid oxygen to lift comparatively light space cargo off the ground.
most rockets in work by combining oxygen and hydrogen and detonating them. To launch sizeable craft from the ground to orbit though, you need alot of oxygen - and its quite heavy. However, if you use normal turbofans to get into the air, then fire a smaller rocket to get you to scramjet speed, and then use the scramjet to ride your way to the top of the atmosphere (where you'll fire one last set of small rockets to propel yourself into orbit), you still have a substantial weight savings over lifting off from the ground with several million lbs of LOX.
This basically means you can lift more cargo into space easier, cheaper, and more frequently.
The only way for the 'space plane' to become a true economic reality is through scramjets.
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