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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.
I'm some one who is impressed by interesting numbers, and I just get a thrill out of the idea of travelling 2 miles per second. That is incredibly cool.
I could do my daily commute in 15 seconds. That would be fun.
i hope that thing has killer A/C...
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...have data on its trajectory? It seems to me that if you want to reduce heat, you need to fly it in a steep climb. Of course, the air then gets thinner, thus providing less boost. Your lifting body is also less effective with that sort of trajectory.
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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
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.
Most children are taught that you can count the seconds between a seeing a lightning strike and hearing a thunderclap and divide by five to determine how far the strike was in miles. This means that the speed of sound (Mach 1) is 5 seconds per mile, i.e., .2 miles per second (.5 km per second, I know...). It should therefore be well known to the same child that Mach 10 (10x the speed of sound) is 2 miles per second.
How soon before someone overclocks it to get Mach 11?
to bridge the gap (cost and speed) between current cruise missiles and ICBMs.
"Prefiero morir de pie que vivir siempre arrodillado!"
"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!
Guys, commercial flight isn't really the goal. Instead, NASA's Hyper-X program, the six-year, $185 million research endeavor of which the X-43A is a part, is aimed at developing vehicles that can deliver payloads into space much more cheaply than traditional rockets.
GMD
watch this
...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?
The energy radiated by a blackbody is proportional to the fourth power of temperature. But since there's a probably whole lot of convection going on, cooling is probably more a matter of moving the heat from the front of the thing to the back, and the naive idea of how things work is probably not too useful.
... but there is still a 2 hour checkin
-- "Can't sleep, clowns will eat me!"
Every time I hear about these scram jet things, I keep picturing the Ghost fighter/Guld Bowman fight from Macross Plus, where Guld's body ends up crushed like a tin can just before his suicide collision with the Ghost fighter.
While it may be possible to control the rate of acceleration to human-tolerable limits, I can't see this being open to anyone who isn't trained and endurance tested prior to flight. How would you explain a flight where half the passengers end up having strokes or heart attacks from the stresses such a beast would generate during an instance of turbulence?
8==8 Bones 8==8
...a moisturizing Indicator® Lubrastrip(TM)...
...features Micro-Power(TM), a gentle pulsing action powered by a Duracell AAA battery.
...allowing a man to shave wherever he prefers.
...and the Duracell AAA battery is easy to insert...
Ugh. Did anyone else get a little creeped out reading some of this shit? They really need to fire whoever came up with stuff like that. Unless they are trying to subliminally market it as something other than a razor.
GMD
watch this
Sounds like one hell of a razor, I'll wait for other people to test it before bringing it anywhere near my face though.
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.
Since it will probably be a suicide mission, let me be the first to nominate Ballmer! DEVELOPERS! DEVELOPAAAGGHHHHHHH!
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.
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How in the world did the goatse.cx guy convince Taco to post that caption?
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"Every artist is a cannibal, every poet is a thief."
I thought that was about X11 and Gnu Mach. Must leave... Go outside.... Air...
So why am I still typing?
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.
And how does that 2 miles per second size up compared to the speed required in order to escape the Earths Gravity and reach orbit?
The Earth is about 8,000 miles diameter, so LEO (about 100 miles above the surface) is 8,200 miles diameter, or 8100*3.1416=25447 miles around. Something in LEO orbits approximately every 90 minutes, it goes 25447/(90*60)=4.7 miles per second. So this 2 miles per second is a little less than half the speed needed to be in orbit.
So while getting into outer space (as SpaceShipOne recently did) is a big achievement, getting enough speed to be in orbit is much more so, requiring even more acceleration.
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Are those mach speeds representing the actuall factor at flying altitude or is there a standart altitude?
Because if its at traveling altitude, your mach 6 35km altitude vehicle would be faster then your mach 7 15km vehicle (speed of sound is presure dependent).
But if it were otherwise, you could travel at mach 1.1 and still be subsonic if you are high enough, which doesnt make sense either.
So why dont they just give the speed in km/h (or mph)? Mach may be usefull if you are dodging around the speed of sound, but at mach 2,3 (or 10), who cares?
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
Trouble with the concord wasn't a technical issue though. It was more of a social/political issue involving the "sonic boom" that it generated over cities and towns. But super sonic flight over water wasn't an issue. As for the scramjet, being that it would be partially in space this may not be an issue. But I wouldn't be the one to give you an answer on that. Anyone else claim to know the answer on this?
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something in earth's orbit hasn't escaped earth's gravity at all. Escape velocity is 11.2Km / sec or over 25,000MPH to leave the earth and never return on an unpowered trajectory. The common weather satellites I read about only have to achieve 17,000+ MPH, so 6Km/sec or almost 4 miles/sec seems a good answer
No, temperature is in degrees Celsius or in Kelvin. There's no such thing as a 'degree Kelvin'.
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