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Mach 10 X43A Flight Successful

Posted by timothy on 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. "

13 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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    Random is the New Order.
    1. 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.

    2. 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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      http://www.frugle.co.uk/
    3. 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

    4. Re:Speed comparison question by Rei · · Score: 3, Interesting

      There's also some other proposals I've seen that use more stages - for example, turbojet->ramjet->scramjet->rocket, so the entire first stage is airbreathing. My favorite for (unmanned!!!) payloads is gun-launch -> scramjet -> rocket. You can to hypersonic velocities in a fraction of a second.

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    5. 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). :)

      --
      Nobody pushes buttons like our bunny. Big red buttons with labels that say "IGNITION", apparently.
    6. Re:Speed comparison question by Fnkmaster · · Score: 2, Interesting

      Or rail gun (i.e. electromagnetic propulsion launch) for the first stage. That would be frickin' cool. Rail gun->scramjet->rocket. And as a bonus, we could put Fed Ex out of business with a rail gun->scramjet unmanned terrestrial package delivery system using the same infrastructure.

  2. NASA sure has come a long way. by Neil+Blender · · Score: 3, Interesting

    Since their first scramjet, the A-1A, flew at 7 feet per second.

  3. 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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    Hulk SMASH Celiac Disease
  4. Re:Good by sik0fewl · · Score: 2, Interesting

    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.

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    I remember when legal used to mean lawful, now it means some kind of loophole. - Leo Kessler
  5. Re:Let's hope... by cplusplus · · Score: 2, Interesting

    My time is worth more than a thimble full of soda and small bag of peanuts :-)

    --
    "False hope is why we'll never run out of natural resources!" - Lewis Black
  6. More questions... by EmbeddedJanitor · · Score: 2, Interesting
    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.

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    Engineering is the art of compromise.
  7. Re:WRONG by drinkypoo · · Score: 2, Interesting

    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.

    --
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