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X43-A on to Mach 10

Posted by CmdrTaco on from the place-hands-on-cheeks-and-pull-back dept.

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."

2 of 459 comments (clear)

  1. Re:Mach 10? by radixvir · · Score: 5, Informative

    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

  2. eeerh... i hate to say this by Anonymous Coward · · Score: 5, Informative

    but Mach 10 won't be 2 miles per second because they are not flying at sea level.

    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 ... )..... (sorry, i know it's bad expressed) being about 287.15 for air

    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