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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."
FYI, he was referring to the episode of Star Trek Voyager, where they test out the new engine technology on the shuttle. It goes Warp 10 which apparently causes 2 of the characters to "evolve" into gecko-like creatures. another completely ridiculous plot that took place around the time of the episode where they found Amelia Earhart
...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.
On a serious note, there are at least technically multiple leading edges on most craft (including this one).
There's the leading edge of the wings, the horizontal stabilizers, the vertical stabilizer, etc. A combat aicraft might have more leading edges for external hardpoints - really, the front-facing part of any protrusion from the fuselage. Whether the nose/front of the fuselage itself is 'technically' a leading edge or not.
Xentax
You shouldn't verb words.
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
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.
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.
So is mine:There are not supporting facts in the Wired blurb because it's public record. The thing in Wired is a little easier to read.
There are no trails. There are no trees out here.
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.
It is a true statement that a Parsec is a measure of distance. But that doesn't rule it out as a unit of time. Special Relativity tells us that time and distance units are interchangeable, because the speed of light is a constant value in all reference frames.
So, while I'm sure the original Star Wars quote wasn't meant to delve into the intricacies of modern physics, it certainly isn't technically wrong. Of course, since a Parsec is about 39 years, I certainly wouldn't want to be piloting for that amount of time...
Oops ... that should have read "... since 12 Parsecs is about 39 years..." You must actually READ your post when you preview it :-)
The whole big deal with the parsec thing is that Han essentially skimmed the event horizons of black holes to get to kessel faster, shaving off time, but in the end, it actually shaved off distance due to spatial anomolies. (sp.)
Read the Han Solo star wars books for it to make sense.
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