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Space

Mach 10 X43A Flight Successful 370

Posted by timothy from the heck-of-a-commute dept.
Sector Bug writes "NASA's X43A research aircraft made its third and final flight today, firing its scramjet engine at Mach 10 (7,000 MPH) or close to it, setting a new record. "
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Mach 10 X43A Flight Successful More

Mach 10 X43A Flight Successful

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  • Speed comparison question (Score:5, Interesting)

    by Drakonian ( 518722 ) on Tuesday November 16, 2004 @07:24PM (#10836818) Homepage
    A (possibly stupid) question: How does this compare to the speed of orbital rockets?

    • Re:Speed comparison question (Score:4, Informative)

      by Holi ( 250190 ) on Tuesday November 16, 2004 @07:29PM (#10836873)
      Not even close.

      Hubbles orbital speed is approximately 16,900 miles per hour.

      • Re:Speed comparison question (Score:5, Funny)

        by cephyn ( 461066 ) on Tuesday November 16, 2004 @07:39PM (#10836985) Homepage
        MPH? we still use that? I thought maybe in this age of newfangled units, we'd at least get like, .41 times that of the Hubble Telescope, or 34.7 times faster than a lambourghini diablo.

      • Re:Speed comparison question (Score:5, Interesting)

        by Fnkmaster ( 89084 ) * on Tuesday November 16, 2004 @07:46PM (#10837062)
        While that is true, this is the first real scramjet implementation. Apparently, people think scramjets will go up to about Mach 15, or over 10,000 miles per hour. While still not low earth orbital velocity, it doesn't have to get there to be useful in getting to orbit.

        If a traditional rocket kicks in at Mach 15 to get the rest of the way to orbit, the savings in launch weight and thus cost from not having to carry all that oxidizer to get up to Mach 15 could still be quite large.

        • Re:Speed comparison question (Score:5, Interesting)

          by Total_Wimp ( 564548 ) on Tuesday November 16, 2004 @08:03PM (#10837235)
          If a traditional rocket kicks in at Mach 15 to get the rest of the way to orbit, the savings in launch weight and thus cost from not having to carry all that oxidizer to get up to Mach 15 could still be quite large.

          I've heard the idea of using three stages in scramjet orbital launches. The first and third are rockets and the middle is the scramjet. It makes me kind of curious about using chemical propellants, like in a giant howitzer, to propell the scramjet to it's initial speed.

          I couldn't see this doing much for manned flight, but most of what we send up isn't manned anyway. It could also have some pretty kick ass millitary application, say for dramatically increasing the payload of current rocket propelled artillery rounds.

          TW

      • WRONG (Score:5, Informative)

        by Anonymous Coward on Tuesday November 16, 2004 @07:48PM (#10837084)
        Not even close.

        Hubbles orbital speed is approximately 16,900 miles per hour.

        You are not even close. He was asking about orbital ROCKETS! Not objects in orbit. Orbital rockets are the things that lift the satellites into orbit.

        The space shuttle does not get anywhere near 16,900 mph on lift off. That is the speed it gradually gets to once in orbit, NOT ON LIFT OFF.

        After 60 seconds, the Shuttle has accelerated to Mach 1 (the speed of sound). About one minute later (two minutes into the flight), the solid rockets burn the last of their fuel. By this time the shuttle is over 25 miles high. The now-empty solid rockets are released in order to reduce the weight carried the rest of the way to orbit. [They parachute into the ocean off the Florida coast, and are recovered to be refilled with fuel and used again.]

        After the solid rockets are released, the shuttle is still attached to the external tank and its launch engines are still being fed propellants from the tank. When the shuttle reaches an altitude of about 57 miles, it changes trajectory to fly more horizontally, and pick up speed. In order to achieve orbit, it needs to accelerate to approximately 17,500 mph (~5 miles/sec). Once it reaches this critical speed (about 8-1/2 minutes after lift-off), the shuttle launch engines are shut off, and the shuttle separates from the external tank. The tank re-enters the atmosphere and burns up on re-entry. It is the only part of the Shuttle system that cannot be used again.

        • Re:WRONG (Score:3, Interesting)

          by drinkypoo ( 153816 )
          The main tank could be used for something other than being thrown away, but we just jettison them. I'd like to see them taken to the ISS and made into modules, or at least placed in the path of orbital debris.

      • Re:Speed comparison question (Score:2, Informative)

        by Anonymous Coward
        Physicists use the metric system, but 16900 mi/h is indeed correct. To clarify this:

        Acceleration of Gravity = Acceleration Centripetal

        ((Gm)/r^2) = (v^2)/r

        G=6.67*10^-11
        m = mass of earth = 5.98*10^24 kg
        r = radius of Hubble from Earth core = 6980000 m

        ((6.67*10^-11)(5.98*10^24))/(6980000^2) = (v^2)/6980000)

        v = 7559.373392 m/s or 16909.83 mi/h
    • LEO satellites move a bit faster than 17,000 Mph, or 2.4 times as fast has the X43A at Mach 10.

    • Re:Speed comparison question (Score:2, Insightful)

      by Anonymous Coward
      Orbital velocity at an altitude of about 150 miles is about 17000 mph (approx 242 km altitude at 27000 km/hr...checked my memory on howstuffworks), so the rocket was going about 0.41 of orbital velocity. In other words, you have only 17% of the kinetic energy you need to maintain an orbit (since KE=0.5*m*v^2). Unfortunately, you have to reach sufficient velocity to coast to the altitude and speed you ultimately want while there is still enough oxygen around you to make the scramjet work. Interestingly, the
    • A related question, how does this (and the speed of orbital rockets) compare to the fastest man-made object (whatever that may be)?

      • Re:Speed comparison question (Score:4, Informative)

        by Christopher Thomas ( 11717 ) on Tuesday November 16, 2004 @07:47PM (#10837078)
        A related question, how does this (and the speed of orbital rockets) compare to the fastest man-made object (whatever that may be)?

        Particle accelerators accelerate anything from electrons and protons to ions close enough to C that the difference is academic.

        For macroscopic objects, I believe compressed-gas guns used for simulating micrometeorite strikes and for producing shockwaves to study things like the metallic hydrogen phase transition accelerate projectiles to tens of km/sec, or larger than but of the same magnitude as orbital velocities.

        Various other types of cannon (the so-called "ram accelerator", used to simulate scramjets, and various flavours of electromagnetic cannon) can also reach projectile speeds in the "greater than but still comparable to orbital" range.

        • Re:Speed comparison question (Score:4, Interesting)

          by frugle ( 769095 ) on Tuesday November 16, 2004 @08:00PM (#10837215) Homepage

          To allow particle accelerators you need to expand your parameters a bit to include natural objects accelerated by man.

          The fastest "man-made" objects - I would hazard a guess at probes sent from Earth to other planets. Voyager 1 travels at roughly 17.4 km/sec or 38,923 MPH

          This will all be put to shame by the Mini-Magnetospheric Plasma Propulsion system (M2P2) - which if it actually got into production and was launched could overtake Voyager1 (launched in 1977 with a 11 Billion Km head start) in 10 years.

          This M2P2 drive in a nutshell would create a 60 km wide magnetic field filled with plasma behind it, trapping the solar wind and propelling it to a predicted 180,000 mph.

          Let's just hope with all that trapped wind they have enough gaviscon to stop it when it gets where it's going...

      • You need to ask yourself one question:

        Relative to what?

        *AKAImBatman hits wviperw over the head with a copy of Einstein's "Special Theory of Relativity"
      • Presumably you mean the fastest man-made object in relation to the solar system's frame of referece. (otherwise it is a harder question to answer because any object going in the same direction as the sun was drifting when it was launched will be going a heck of a lot faster than an object going in the opposite direction of which way the sun was drifting.) I don't know, for example, if the Voyager craft are headed in the same direction as the sun (in essence, blazing a trail in front of it), or if they are

      • A related question, how does this (and the speed of orbital rockets) compare to the fastest man-made object (whatever that may be)?

        I thought the fastest man-made object was Pioneer or Viking at around 45k mph. However, a quick Google indicates that Helios [aerospaceweb.org] supposedly traveled at 150,000 mph.

        I'm positing that the particles in particle accelerators are not "man-made" in this context.
    • Shuttles re-enter at Mach 20. Atmospheric friction force is the square of velocity. So an orbital vehicle has to have four times the strength of X-43 and sixteen times Space Ship One.
    • The scram jet is air breathing. One wonders how much air is available to breath at 110,000 foot. Is there something majic about 110k feet? Is there too little air above this? Is this the altitude limit of jet technology?

      Considering that GPS satellites are something over 20000 km up, 110k feet is only a fraction of a percent of getting there.

    • A (possibly stupid) question:

      The only stupid question is an unasked one.
      Any fool can ask a question which the wisest of men cannot answer.
      Too many cooks spoil... Wait, no, that's nothing to do with it.

    • The article kind of hinted at something:
      • "This flight is a key milestone and a major step toward the future possibilities for producing boosters for sending large and critical payloads into space in a reliable, safe, inexpensive manner," said NASA Administrator Sean O'Keefe.

      So, for what it's worth, escape velocity [wikipedia.org] is 25,000 mph [google.com], so a scramjet would be perhaps the second of at least three stages to getting into space.

      Are there any Aerospace engineers who can comment? Are scramjets supposed to be more

      • Re:Speed comparison question (Score:5, Interesting)

        by Rei ( 128717 ) on Tuesday November 16, 2004 @09:35PM (#10838041) Homepage
        IAMAAE, but the reason that they're more economical is that you only need to carry up ~1/9 of your propellant mass during the airbreathing stage. For example, a LH/LOX rocket uses 2 H2 + 1 O2 -> 2 H2O; For molecular weights, H2~=2, O2~=32; thus, the ratio is (32+4)/4 -> 9 times as much mass for the LH/LOX rocket.

        More importantly, however, is the fact that the more mass your craft has, the more energy it takes to accelerate that mass; consequently, craft masses grow geometrically with a given desired increase in delta-V. The net benefit from only needing to carry up your fuel is staggering. Even if you use a hydrocarbon fuel (much denser, which is a very good thing, plus often not cryogenic), you're still going to get at least a 6-fold instantaneous mass difference (which, again, becomes more dramatic as you factor in how much it saves you from having to accelerate propellant).

        Also, they're theoretically simpler, lower maintainance, and less likely to fail because of the reduced number of moving parts. They're just in general Good Things(tm). :)

  • With apologies to Marvin (Score:5, Funny)

    by daeley ( 126313 ) * on Tuesday November 16, 2004 @07:24PM (#10836819) Homepage
    X43A blurs past the camera. It is silent.

    Marvin: "Where's the kaboom? There was supposed to be an earth-shattering kaboom!"

    EARTH SHATTERING KABOOM!

    Marvin: "At last!"

  • I guess it is the first 7000MPH post (Score:5, Funny)

    by roman_mir ( 125474 ) on Tuesday November 16, 2004 @07:24PM (#10836822) Homepage Journal
    we shall call it the ludicrous speed.

  • NASA sure has come a long way. (Score:3, Interesting)

    by Neil Blender ( 555885 ) <neilblender@gmail.com> on Tuesday November 16, 2004 @07:25PM (#10836830)
    Since their first scramjet, the A-1A, flew at 7 feet per second.
  • Man,

    I need one of these engines for my SAAB.

  • News Delayed (Score:3, Informative)

    by iamlucky13 ( 795185 ) on Tuesday November 16, 2004 @07:25PM (#10836838)
    Meanwhile, CNN is still reporting [cnn.com] the flight as being delayed on the front of their Science and Space page.

  • Also last flight of the B-52B mother ship ... (Score:5, Interesting)

    by xmas2003 ( 739875 ) on Tuesday November 16, 2004 @07:27PM (#10836852) Homepage
    The B-52B (tenth off the assembly line) first flew on June 11th, 1955 and among other things, has carried the X-15, Shuttle solid rocket booster, and finally the X-43A (on the same pylon as used by the X-15). Read more about the ol' BUFF at NASA. [nasa.gov]

  • Mach (Score:5, Funny)

    by MikeMacK ( 788889 ) on Tuesday November 16, 2004 @07:27PM (#10836853)
    "Mach Number" was named after the Austrian physicist Ernst Mach.

    I understand he was a very fast guy, much to his wife's chagrin.

    • and Mach also named "Mach Bands", a psychophysical illusion when gradients of light and dark are next to each other: the edge of the light region appears even brighter and the edge of the dark region appears even darker than it truly is. A series of graduated intensity bands will appear to be non-linearly illuminated because of the contrast-enhancement performed by ours retinas and cortices... (retinae?)

  • Good (Score:5, Funny)

    by Dark Paladin ( 116525 ) * <jhummel.johnhummel@net> on Tuesday November 16, 2004 @07:28PM (#10836868) Homepage
    Now, when I tell those guys I want my pizza in 30 minutes or less, there is no excuse!

    • Re:Good (Score:3, Interesting)

      by sik0fewl ( 561285 )

      Unless, of course, you live on the far side of an airport and they can't get clearance to fly across it. In that case (assuming they had to fly all the way around the world the other way) your pizza would take about 3.5 hours to arrive.

      Still better than some places I've ordered from.

    • That stupid 30 minutes or less crap was done away with a long time ago.

      Y'know why? Heh...there were incidents of drivers getting in huge car wrecks and their bosses running up to the scene, taking the pizza, and running to the customer's door to beat the time.

  • Guinness Record (Score:4, Funny)

    by Embedded Geek ( 532893 ) on Tuesday November 16, 2004 @07:30PM (#10836885) Homepage
    In case you're wondering, it beat its own world record [nasa.gov] (Mach 6.83, 5000MPH) set back in March.

    By the way (and massively OT), doesn't a "Guinness Record" sound like something you'd like to break yourself, at least if it involved consumption?

    • The folks at NASA are probably in the bars right now celebrating and breaking their own Guinness records.

  • Muuuuch better shot for scale... (Score:5, Informative)

    by Anonymous Coward on Tuesday November 16, 2004 @07:31PM (#10836898)
    ...had to hunt for it, but here it is:

    http://spaceflightnow.com/news/n0106/02x43failure/ x43.jpg [spaceflightnow.com]

  • Jobs (Score:3, Funny)

    by Anonymous Coward on Tuesday November 16, 2004 @07:31PM (#10836910)
    Steve Jobs invented mach speed.

  • Let's hope... (Score:5, Funny)

    by HexaByte ( 817350 ) on Tuesday November 16, 2004 @07:34PM (#10836933)
    Let's hope that this type of engine isn't adopted by commercial arlines. If it were, a flight cross country would take less than an hour, and the flight crew wouldn't have time to get us all drinks and peanuts.

  • That 's around 12 000 Km/h (Score:5, Informative)

    by ArcticCelt ( 660351 ) on Tuesday November 16, 2004 @07:36PM (#10836953)
    That's around 12 000 Km/h for those who use the more civilized metric system.

    (sorry I know this debate is a classic but miles say nothing to me and I guess that many international slashdoters feel the same)

    • Mods, come on, that's hardly a flamebait. I for one found it informative, although I'd phrase it "more common metric system" (common as in the rest of the world, I do know most slashdotters are from the States)

    • That's km/h (Score:5, Funny)

      by SysKoll ( 48967 ) on Tuesday November 16, 2004 @08:33PM (#10837512)
      12000 Km/h is Kelvin times meter per hour. A Kevin is centigrages counted from the absolute zero. For laymen, the association of a temperature with a speed unit is a bit baffling, so let me explain. Km/h is a unit used exclusively to measure the speed reached by those people that run around at high speed while yelling "AAAAARGH! MY UNDERWEAR IS ON FIRE!!!". That's right, the dreaded Underwear Spontaneous Combustion Syndrome, often caused in young guys oogling all these hot chicks in Californian campuses. Witnesses of an USCS occurence generally scramble for water buckets.

      An USCS episode can be dramatic, depending on the Km/h value. At high Km/h values, the victim is running so fast that the bucket carriers cannot catch him. On top of that, the wind of his frantic run vents the fire, which of course burns even hotter, quickening his race. After a certain threshold, the poor guy's genitals burns to a crisp. The critical speed is called "Mach speed" (pronounced Mack), after an early victim.

      So unless you are referring to these sad but uncomon accidents, the metric unit you want to use is km/h, with a small k meaning kilo, not the capital K of Kelvin.

    • That's around 12 000 Km/h for those who use the more civilized metric system.

      Is that metric hours?

  • Yes but... (Score:5, Funny)

    by wviperw ( 706068 ) on Tuesday November 16, 2004 @07:40PM (#10836988) Homepage Journal
    The important question is, what would Mach 10 be in warp speed?

  • You know.. (Score:4, Insightful)

    by bludstone ( 103539 ) on Tuesday November 16, 2004 @07:40PM (#10836990)
    For all the shit theyve been through, NASA still fucking rocks.

    Kudos to the Alpha geeks.

    We bow.
    • actually, you should have said:

      for all the shit they've been through, NASA still fucking rockets (insert cymbal crash)

      Thank you, thank you- i'll be here all week!

  • X-10? (Score:2, Offtopic)

    by necro2607 ( 771790 )
    Did anyone else think of "X-10" when they saw this article's title? ... or even better... "We must destroy X-10... we must destroy all internet ad".. ??

  • At Mach 10 (Score:5, Funny)

    by boatboy ( 549643 ) on Tuesday November 16, 2004 @07:53PM (#10837133) Homepage
    So, at Mach 10, can anyone hear you scream?

  • I'm Not Impressed (Score:3, Funny)

    by nate nice ( 672391 ) on Tuesday November 16, 2004 @07:54PM (#10837142) Journal
    <typical slashdotter>It's not like they put it into space, twice in two weeks, for under 10 million dollars.</typical slashdotter>
  • NASA has scheduled a press conference at 4 PST. It's available at http://www.nasa.gov/multimedia/nasatv/index.html
  • Nasa is doing these tests because they can't model conditions with their computers.

    I wonder exactly what about the scramjet that they can't model with the resources they have including plasma wind tunnels ?

  • But can it do... (Score:5, Funny)

    by dark-br ( 473115 ) on Tuesday November 16, 2004 @08:12PM (#10837306) Homepage
    ...the Kessel run in under twelve parsecs? ;)

  • The article link doesn't have much in the way of interesting details, so, here are some slightly better links to hopefully raise the signal ratio:

    • http://www.nasa.gov/missions/research/mach10_me t eor.html
    • http://www.nasa.gov/missions/research/x43-image- feature.html

    The first one is an article with some details, the second is some artwork that explains the scramjet and the flight path.

    From the looks of it, the scramjet engine doesn't appear to be a very sophisticated device. It's just a funnel that do

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