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X-43A Hits Mach 7
quiggy writes "As previously reported, NASA tested the X-43A yesterday. The results are in, and the scramjet hit Mach 7, setting a new speed record. CNN is also reporting the story, with a note that a similar jet could be tested by the end of the year, hopefully reaching Mach 10."
Of course, rockets launched into space have to travel at least 11.18 km/s to reach escape velocity, which is a lot faster than mach 7. This isnt a speed record, really more of a design change in that the engine doesn't need to carry its own oxygen.
Congrats to NASA though.
http://almostsmart.com
I've always been under the impression that escape velocity is if a projectile was fired at ground level, and has no boosting at any later point. Space rockets are continiously accelerated upwards, and thus dont need to reach such speeds.
when will we see warp engines? Shortly after someone proves that its not impossible I guess.
Turns out oxygen is heavy, and kind of a pain in the ass to package anyway. It's much more convienent if you can just use the oxygen that's laying about, which is significantly more difficult that it sounds when you're traveling at hypersonic speeds.
Damn gravity.
Yes, we've done Mach 7 before. And the space shuttles & space probes go much faster. The big deal is the engine. It's like comparing a nuke to some kilotons of TNT. Sure they may have the same effect (Mach 7), but one is simply a gigantic waste of resources (fuel), the other is a valuable invention. And considering it's the military, for good or bad...
Kjella
Live today, because you never know what tomorrow brings
Speed is a number and velocity is a vector. So an escape velocity can vary in speed as the angle of escape changes.
If space rockets are perpendicular (well, they're not really) to the tangent of the atmosphere on exit, their speed still has to be enough to let them escape, but this speed can be really low - I take it implicitly you mean the firing of the rocket is necessary to overcome gravity rather than to reach a certain speed. Conversly, planes in the outer atmosphere can go really fast (speed) but as their velocity does not have a vector pointing upwards they won't exit.
Acceleration has little to do with it other than making the escape more efficient (of course the rocket changing vector is also acceleration).
good work scientists :)
ENGINEERS had more to do with getting this ship up to Mach 7 that did the scientists!
Looks like the guy who did this reporting for CNN isn't much of a techie. A few things he got wrong: (1) "scramjet, which uses air for fuel" -- quite a few people will read that as not requiring ANY onboard fuel at all. (2) "shortening the trip between New York and London to less than five hours" -- we can already do that in LESS than 5 hrs. (3) "it flew under its own power for six minutes to do maneuvers over the ocean" -- if you count gravity as its own power. It was only powered for 10 seconds under the scamjet, and "glided" the rest of the way to splashdown.
Now this intrigues me: It was taken to mach 5 by the Pegasus, then it accelerated under the scramjet to mach 7, BUT the engine was only lit for 10 seconds. Does that mean this succer gained nearly 1400mph in 10 seconds???? Wonder what it would do in the quarter? How many Gs is that?
If I didn't have absolutely NOTHING to do, I wouldn't be here.
I don't know if there is an independant peer review of their data but from their web site University of Queensland Hyshot Program Nasa's own press release doesn't say that they broke any records.... Either way Kudos to NASA....maybe now we'll get cheaper access to space
brrrrrrrrrppp 'Ey Homer...Why don't girls like me?
Alcubierre's idea was that the ship doesn't move. Instead, it modifies the space around it much like an esclator.
I'm with you so far.
However, at this time, there was a problem with obtaining the required energy, which was quite alot [think total solar output of the sun in its current life, per second].
The main stumbling block to Alcubierre's drive is that it requires negative energy. My understanding is that the human race can't produce that right now, at least in appreciable quantities.
All of the FTL drive concepts that I've seen involve something currently unobtainable (or outright impossible) like this - infinitely long neutronium rods, creation of a pocket universe to put the ship in, etc.
In 1999, however, Thomas Valone spotted an answer. Zero Point Energy.
No. Pseudo-science can solve lots of problems theoretically, but it is not the answer to real-world problems.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
http://www.mech.uq.edu.au/hyper/hyshot/:
9 :
As the spent motor and its attached payload falls back to Earth, they gather speed, and the trajectory is designed so that between 35km and 23km, they are travelling at Mach 7.6
http://www.uq.edu.au/news/index.phtml?article=346
The recent HyShot(TM) launch was designed to take the scramjet engine to a speed of Mach 7.6 (or more than seven times the speed of sound) for the experiment, using a Terrier Orion rocket. The rocket and payload reached an altitude of 314km before the rocket was configured to fly in a new trajectory pointing the payload back down to earth.
HyShot was simply free-falling to earth in order to reach Mach 7.6 so the engine could be ignited. It achieved that speed regardless of whether or not the scramjet fired. The X-43 was flying horizontally, and was actually powered by the scramjet engine during a controlled flight.
So there is a difference between what was accomplished. The distinction is that HyShot achieved combustion, while the X-43 was the first scramjet powered craft to be flown.
Dan East
Better known as 318230.
"News is supposed to be 'PC'"
The term "Politically Correct" (PC) is a satirical epithet applied to liberal doctrine by conservatives. It mocks the presumption that liberal opinions are the "correct" opinions, in an absolute sense, not one perspective among many.
The term "PC" is made more amusing to conservatives by the liberals' conviction of their own political correctness preventing liberals from recognizing the joke that liberals' are unawaredly convinced of their own political correctness. "Of course our beliefs are the correct beliefs, why is that funny ?" ask the liberals.
Which brings us to your assertion that "News is supposed to be PC" What you are telling us ?
1. That news should be reported from a liberal perspective because...
2. Liberals are right and conservatives are wrong.
3. You are blind to the fact that you are promoting your own perspective in absolutist terms.
Note, "PC" denotes both the status of a particular belief as liberal and the associated presumption of correctness. For example, consider the statement "Johnny failed first grade, but he is African-American, therefore holding him back at that grade level would not be PC". In this sentence, "PC" serves to associate with liberals the principle that unqualified indviduals should be promoted if they are members of a particular ethnic group. But "PC" is also meant to characerize the attitude of those who would defend that principle as an absolutist faith that they are "right" and others are "wrong".
Fox News is unpopular with liberals not becuase it sets forth alnternative and consertavie "correct" notions, but because it undermines the very notion of correctnees in political discourse. Fox betrays the news broadcast tradition of delivering news in somber, ministerial tones which close off question and doubt; "Though shalt not question the word of Jennings". "The shalt now question the word of Brokaw." The informal on-air attitude of Fox news is like "Here are our correspondents and here is what they seem to to think is going on." It's more upbeat and friendly. We are allowed to ask questions. Fox news conveys to television viewers the dangerous attitude that what you see on TV is people telling you what they think is going on, not sacred and unquestionable truths. It undermines the notion of TV news as a conduit for absolute and correct truths, subverting the entire system of liberal propagandizing through control of unexamined "correct" news content.
News should not be PC.
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