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Mach 10 X43A Flight Successful

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. "

28 of 370 comments (clear)

  1. Speed comparison question by Drakonian · · Score: 5, Interesting

    A (possibly stupid) question: How does this compare to the speed of orbital rockets?

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    1. Re:Speed comparison question by Holi · · Score: 4, Informative

      Not even close.

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

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    2. Re:Speed comparison question by cephyn · · Score: 4, Funny

      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.

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    3. Re:Speed comparison question by Fnkmaster · · Score: 5, Interesting

      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.

    4. Re:Speed comparison question by frugle · · Score: 4, Interesting

      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...

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    5. Re:Speed comparison question by Total_Wimp · · Score: 4, Interesting

      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

    6. Re:Speed comparison question by Rei · · Score: 4, Interesting

      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). :)

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    7. Re:Speed comparison question by mazarin5 · · Score: 5, Funny

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

      No no no, you're looking at it all wrong...

      The particle accelerator is a man-made object accelerated to 0.99c.

      You just have to use the electron's frame reference!

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      Fnord.
  2. With apologies to Marvin by daeley · · Score: 5, Funny

    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!"

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  3. I guess it is the first 7000MPH post by roman_mir · · Score: 5, Funny

    we shall call it the ludicrous speed.

  4. Also last flight of the B-52B mother ship ... by xmas2003 · · Score: 5, Interesting

    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.

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    1. Re:Also last flight of the B-52B mother ship ... by Wyatt+Earp · · Score: 4, Informative

      It's the last flight of the B-52B mothership, but it is being replaced with an H

      http://www.dfrc.nasa.gov/Gallery/Photo/B-52/HTML /E C03-0258-04.html

      Parts for the engine were becoming rare and costly for the B

  5. Mach by MikeMacK · · Score: 5, Funny
    "Mach Number" was named after the Austrian physicist Ernst Mach.

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

  6. Good by Dark+Paladin · · Score: 4, Funny

    Now, when I tell those guys I want my pizza in 30 minutes or less, there is no excuse!

  7. Muuuuch better shot for scale... by Anonymous Coward · · Score: 5, Informative

    ...had to hunt for it, but here it is:

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

  8. Let's hope... by HexaByte · · Score: 5, Funny

    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.

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  9. That 's around 12 000 Km/h by ArcticCelt · · Score: 5, Informative
    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)

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  10. Yes but... by wviperw · · Score: 4, Funny

    The important question is, what would Mach 10 be in warp speed?

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    1. Re:Yes but... by otis+wildflower · · Score: 4, Insightful

      TOS Warp or Next Generation Warp?

    2. Re:Yes but... by happyfrogcow · · Score: 5, Funny

      TOS Warp or Next Generation Warp?

      You should win a free slashdot premium subscription for that question.

      Nerd of the Day honors to you!

  11. WRONG by Anonymous Coward · · Score: 5, Informative

    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.

  12. Re:Someone help me out here. by richmaine · · Score: 4, Informative

    Please, if you are pretending to supply information, make it at least vaguely close to correct. :-(

    The rocket boosted it all the way up to max speed. The scramjet wasn't even lit at quite the max speed, though close (the research vehicle decelerates slightly in the few seconds after separation from the rocket before the scramjet lights).

    The scramjet *MAYBE* did as well as stopping the deceleration for a few seconds. One of the researchers, who I was talking to as we watched the B52 flyby and landing, said that he thought perhaps they got just a little positive acceleration (i.e. it sped up slightly), but small enough that he couldn't tell for sure from the quick look he took so far.

    But then, that is what was being aimed for.

  13. At Mach 10 by boatboy · · Score: 4, Funny

    So, at Mach 10, can anyone hear you scream?

  14. But can it do... by dark-br · · Score: 4, Funny

    ...the Kessel run in under twelve parsecs? ;)

  15. Re:How fast is 7,000 MPH by JohnGrahamCumming · · Score: 4, Insightful

    > Circumference of Earth at equator = 24,900 miles = 3 hours 33min 26 seconds

    Please, if you get a scramjet of your own, take the extra time to go around the earth and fly above sea level! You'll enjoy the trip a whole lot more.

    John.

  16. That's km/h by SysKoll · · Score: 4, Funny
    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.

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  17. Re:Wasting nearly-Orbital Material by DasBub · · Score: 4, Informative

    "What I don't understand is why you spend so much money in fuel and oxidiser to get the external tank nearly into orbit, then for the additional cost of presumably not very much (in the scheme of things), let the thing fall back to earth and burn up?

    Would it not make more sense to take the tank into orbit and use it for something? It's got to be (at least nearly!) air-tight, why not add it to the Space Station as another module for something? Use it for spare parts - got a leak, hack a suitable sized bit off the old tank and stick it over the hole. Just stack them up in orbit somewhere for raw material to build a interplanetary space ship?"

    You're absolutely correct. Unfortunately, a lot of factors and events have stopped any of these things from happening.

    The ET itself is completely space-worthy. It was designed to operate in space long after reaching orbit. Early plans for space stations and platforms included the ETs since they remain completely useable. What's more, the tanks still have a lot of H2 and O2 left after a launch. So in reality, the shuttle could reach much higher orbits if it _kept_ the ET attached on orbit. This was purposely designed-in, since the original plans for what's now the ISS called for a higher orbit than usual. So any visit to the space station would require one to keep the ET. Even if it was just hanging around LEO, the H2 and O2 in the tank are extremely valuable and are worth leaving in orbit.

    So why don't they do this? Well, they just don't have a reason to anymore...

    First, the shuttle no longer needs access to the higher orbit, since the ISS we have is in a much lower orbit. This was done to accomodate the Russian launch sites. This has crippled a lot of the usefulness of the ISS compared to it's original goals, but that's a whole other post.

    Second, managing the ETs and their contents are more trouble than they're worth. What I mean is that the only immediate usefulness of the H2 and O2 would be for the ISS, but it's just less of a planning headache to have the supplies sent up by Progres than mapping out astronaut time to transfer stuff from the ET through the shuttle to the station (and having to manoeuver with the ET attached). We can say that making orbital warehouses of the tanks and their contents for future missions and projects is a great idea, but it brings up the question of where and how. Do you store them at the ISS, or at some designated point out of the way? If the ISS, you've just added another headache to the crew. If at some other point in space, you have to have station-keeping thrusters to maintain orbit and attitude. NASA has no need for any of these headaches currently.

    Thirdly, the whole idea is moot since the shuttle's death warrant has already been signed. Well, it was signed a long time ago, but suffice it to say that the shuttle isn't going to be around much longer. There's no incentive to change their operations now, so they'll just keep chucking everything away until the program is over.

    It's really quite sad to look back at the past thirty years* of the shuttle and ISS programs and realize how poorly they've been executed and how many opportunities and resources have been squandered needlessly. I have the utmost respect for the engineering teams and all the people who put the shuttles together and made them fly, but the shuttle program really has ruined NASA for decades.

    Blah.

    * - the shuttle fleet has only been flying since '81, but the design work began in the early 70's

  18. rather than leaving a card through the letterbox.. by RMH101 · · Score: 4, Funny

    ...instead you'd have your house, garden and neighbourhood replaced with a huge crater with a squashed packet from amazon in the centre?