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X43-A on to Mach 10
Cat_Byte writes "On March 28 we read about the X43-A hitting Mach 7 with a successful scramjet test. Prior to that on June 2, 2001 the craft tore itself to pieces during a trial run. Well now they are preparing to hit Mach 10. The upcoming Mach 10 run of the X-43A appears to mark an end of the program. The seven-year, approximately $250 million Hyper-X program was created to provide unique "first time" data on hypersonic air-breathing engine technologies.
"At Mach 7, the front leading edge of the vehicle would see about 2,400 degrees Fahrenheit. At Mach 10, its probably twice that -- twice the heat load essentially," Sitz explained
FYI, Mach 10 is about 2 miles per second."
Wait, maybe I'm thinking of something else...
-Rob
Marriage doesn't have to suck!
It's great to see the Air Force putting that Ga'ould and Asgard technology to good use. That Stargate program is really paying off.
Blinkx and You Will Miss It?
Ah, but does it get 1700 miles per gallon?
Holy crap, they're up to Mach 10 now? I guess I'm going to have to throw my old razors away. You'd think that a razor with 10 blades would be rather unweildy but I sure as hell am not going to let my neighbor Jones beat me in the male-gromming-department! Man, those old Mach 3 blades were already pretty expensive. I hate to see how much this new shit is gonna cost...
GMD
watch this
I could do my daily commute in 15 seconds. That would be fun.
Oh, you can have a commute like that right now. It's the stopping that's the problem.
Javascript + Nintendo DSi = DSiCade
Two miles per second is an almost unfathomable speed to me. It's like me trying to fully grasp the vast distances of the universe. I just can't do it.
Not everything is analogous to cars. Car analogies rarely work.
How does the Slashdot Effect happen given that no slashdotters ever RTFA?
Two miles per second means you can cross the Pacific in under an hour.
It's still going to take 4 hours just to get to the airport, check your baggage and get through security.
Just wait until everybody has one of these. Rush hour traffic will really be a rush. Will they make these as convertibles? I love the feeling of wind blowing by as I drive.
for maximum effect, the preceding post should be read monotone and at a steady cadence
How soon before someone overclocks it to get Mach 11?
"At Mach 10 -- or 10 times the speed of sound -- the X-43A is traveling at about two miles per second. Thats in the range of 7,500 miles per hour."
Which sounds really impressive until you realize that escape velocity is 25,000 miles per hour and we are less than a third of the way to an air-breathing launch vehicle.
186,000 mi/sec... it's not just a good idea, it's the law!
because slashdot outsourced their moderator duties
Knowing English is not a requirement.
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...the craft tore itself to pieces during a trial run.
I was under the impression that the Pegasus boost missle went out of control so they self-destructed it...not that there was a problem with the X-43.
why do we even know about this? Shouldn't this be some classified secret or do they already have craft that handily surpass mach 10 and thus don't care if we know about it? The stealth project was a secret for over 40 years and they're just parading this around (arguable if equal importance) for the cameras...what gives? What secret shit are they NOT telling us about I wonder.
the Kessel run in under twelve parsecs?
As long as he's not talking about zooming to uranus...
but Mach 10 won't be 2 miles per second because they are not flying at sea level.
... )..... (sorry, i know it's bad expressed) being about 287.15 for air
Mach number is the square root of the product of gamma, R, and T. Being:
gamma a propertie of the gas (1.33~1.44 aprox for air),
R the constant of the gas (universal R over Molecular Mass for every kilo
And T is the absolute temperature of the gas;
According to the International Atmosphere model, the temperature of air drops 6.5K every kilometer until you reach 11Km, beyond it remains constant until 22km, where it again rises.
So, if depending of the height (and particular condition of the day and the state of atmosphere) the Mach speed varies
As i haven't seen at what height they are flying, you can calculate yourself the Mach speed if you find the numbers.
So is very probable that they are flying at really great heights where the mach value greatly differs from sea level Mach, what is taught to children, as other poster suggested
Values of temperature of atmosphere can be found looking for ISA model (International Standard Atmosphere)
By the way, i am using SI; so, if you find a table with Farenhait (or whatever it is spelled) you can convert a farenheit degree to kelvin via:
(TF-32)/1.8+273 = kelvin
PD: Sorry for my bad english
I can hear it now ludacriss speed GO! To me Spaceballs 2 coldnt come fast enough.
I'm sorry, Fry, but astronomers renamed Uranus in 2620 to end that stupid joke once and for all ...
(S(SKK)(SKK))(S(SKK)(SKK))
I hear they are planning use the heat dissipation techniques from this project in heatsinks for prescott processors.
What's it called now?
Urectum.
"Prefiero morir de pie que vivir siempre arrodillado!"
General Tufnel: The Mach numbers all go to eleven. Look, right across the board, eleven, eleven, eleven and...
Reporter: Oh, I see. And most planes go up to ten?
General Tufnel: Exactly.
Reporter: Does that mean it's faster? Is it any faster?
General Tufnel: Well, it's one faster, isn't it? It's not ten. You see, most pilots, you know, will be flying at ten. You're on ten, all the way up, all the way up, all the way up, you're on ten on your airspeed. Where can you go from there? Where?
Reporter: I don't know.
General Tufnel: Nowhere. Exactly. What we do is, if we need that extra push over the cliff, you know what we do?
Reporter: Put it up to eleven.
General Tufnel: Eleven. Exactly. One faster.
Reporter: Why don't you just make ten faster and make ten be the top number and make that a little faster?
General Tufnel: [Pause] These go to eleven.
If Slashdot were chemistry it would look like this:Cadaverine
It's incorrect to use temperature to describe something as "twice as hot," since temperature is an intrinsic value - not a "quantity" to be counted like length, mass, etc, but rather a relative scale, defined by the Zeroth law of Thermodynamics to describe the direction of heat transfer.
It would be somewhat more correct to possibly describe something as having twice as much internal energy (heat), because units of heat (joules or BTU's) are quantifiable units. Keep in mind that this still wouldn't lead to twice the temperature on an absolute scale, since the specific heat of virtually anything is variable with temperature - hence, you can't correctly surmise that just because there's twice as much heat then there must be twice as much temperature.
When you're not looking, this sig is in Latin.
"from the place-hands-on-cheeks-and-pull-back dept."
How in the world did the goatse.cx guy convince Taco to post that caption?
-------
"Every artist is a cannibal, every poet is a thief."
I thought they killed off Data in the last movie. I guess not.
Best Slashdot comment ever
At that speed a brick is a "lifting body". Reminds me of the F-15 a.k.a. the "Aluminum Lawn Dart" (or world's most expensive lawn dart) because if you turn off the engine thats what your flight path looks like.
He's Q. He can resurrect Data if he wishes...
Prior to that on June 2, 2001 the craft tore itself to pieces during a trial run
Actually, it's the rocket launcher that veered out of control.
A plane takes the rocket+X43 into a given altitude, the rocket launches bringing itself and the X43 to about Mach 3 and then the scram jet can take action, bringing the X43 up to Mach 7 after separation from the rocket.
It's the rocket that failed on the first attempt. Not the X43-A.
What I find interesting is that the leading edge heating only doubles between mach 7 and mach 10. For macroscopic objects, drag is proportional to v^2, so the drag coefficient must decrease a lot faster than I thought.... I should modify my rocket simulator. :) Unless, of course, they're travelling at a different altitude (?).
Uhh... 7 squared is 49 and 10 squared is 100. What's your problem?
-- John Dierdorf, Austin TX