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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.
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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.
the point is to gain the capability to bomb anyone in the world really quickly .
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
it is a speed record for air breathing engines.
I am the Alpha and the Omega-3
People keep saying this... AFAIK "escape velocity" is the "muzzle velocity" a projectile would need to start with in order to escape the Earths gravity. But this doesn't apply to a projectile that accelerates with it's own power (ie. rocket).
"Ignorance more frequently begets confidence than does knowledge"
- Charles Darwin
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).
Proof of concept.
It worked for 10 seconds. That was all this design is supposed to do, and all it is likely capable of doing, but it proved their combustion chamber design works.
Now they can strap big fuel tanks on and go for a longer sustained burn, if they want to.
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Mod me down, you fucking twits. Go ahead. I dare you.
(I read with sigs off.)
Mod me down, I'm an idiot. That speed of 11.18 km/s assumes there will be no further boost during flight, and is the speed of the vehicle right when it leaves the ground. So, the vehicle can go much slower, as long as there is acceleration throughout the flight.
good work scientists :)
ENGINEERS had more to do with getting this ship up to Mach 7 that did the scientists!
Not exactly. We're sacrificing most everything for the Bush program to plant a flag in Baghdad.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
I'm perplexed by the fact that NASA intentionally threw away the plane before they'd done a post-mortem. The airframe could yield an awful lot of information about how well the craft stood up to the stress and yet they just let it sink in the Pacific. Seems to be either a waste of valuable information or suggests that this is more a publicity stunt than science.
I think this programs future has been uncertain because of the uncertainty of its success. Remember what happened to the first one. Governments tend to be very wary of failure in expensive scientific endeavors, even if those failures teach us lessons necessary to succeed. Now that they've had a pretty stunning success, at the very least the millitary is going to be VERY interested in continuing this project (they're already funding this part) and even if NASA's budget doesn't allow for continuing this program with current priorities, I think the Military has been convinced this is a direction worth pursuing further. Just a guess on my part, but I bet you see new funding quite soon.
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.
Doh.....I'm gonna get flamed. I read more closely. Orbital mechanics tells us that the velocity of an orbiting object is dependent on the mass of the object you're orbiting, and the distance you are from the surface. The mass of the Earth determines the Acceleration due to Gravity; and thus the orbit for a given velocity. He's correct and i am a dumbass!
brrrrrrrrrppp 'Ey Homer...Why don't girls like me?
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.
The only thing is, during much of the acceleration time, they will have to use a different type of motor, since a scramjet motor will not work at lower speeds.
However they get up to minimum scramjet ignition speed, there is likely to be a pretty good kick in the pants when the scramjet ignites.
And the question of how they get up to that speed is a very important one to work out. If a rocket is used, then acceleration will be very brisk. Also, if you are going to use a rocket anyway, why bother with the scramjet at all? (In fact, a lot of people feel that scramjets are a solution in search of a problem.)
If a rocket is not used, then what will get you up to that speed? They could climb to 70,000 feet, then go into a power dive to start the scramjet, but can you imagine the G's when you pull out of a dive at hypersonic speed?
I'm not saying it can't work, I'm just pointing out that there are many issues to resolve before commercial flights are remotely feasible.
For very high speed travel, leaving the atmosphere may be the way to go. Hypersonic atmospheric travel is almost like constant re-entry. And designing a craft to get up to those speeds from horizontal takeoff is no joke.
Just some things to think about.
MM
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