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SpaceX's Grasshopper VTVL Finally Jumps Its Own Height

cylonlover writes "The SpaceX Grasshopper vertical takeoff vertical landing (VTVL) testbed has successfully flown to a height of 40 meters (131 ft), hovered for a bit and subsequently landed in a picture perfect test on December 17, 2012. The Grasshopper had previously taken two hops to less than 6 m (20 ft) in height, but the latest test was the first that saw it reach an altitude taller than the rocket itself, which is a modified Falcon 9 orbital launch vehicle. The flight lasted 29 seconds from launch to landing, and carried a 1.8 m (6 ft) cowboy dummy to give an indication of scale."

12 of 111 comments (clear)

  1. Re:YAY !! 1952 ALL OVER AGAIN !! by bill_mcgonigle · · Score: 3, Funny

    Welcome to The Short Attention Span Era !!

    Patience, Grasshopper.

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  2. Re:YAY !! 1952 ALL OVER AGAIN !! by tulcod · · Score: 3, Interesting

    The fact that we got to the moon was a coincidence: we got there by trial and error, instead of careful analysis on error bounds, and actually making sure everything works before launch. This is exemplified by the many failed (!) Apollo missions.

    This time, we're carefully doing all the calculations, and you can see this from the fact that SpaceX has not yet failed any mission, even though they have exactly the same missions as we used to.

  3. Re:Whats the advantage of this tech? by dreamchaser · · Score: 3, Informative

    I really can't see one. It seems like a massive waste of fuel to carry more stores on board then land vertically. Couldn't there be a better way of slowing descent in the atmosphere and recovering the module, like parachuting it into the ocean?

    Quicker and cheaper recovery, enabling it to be reused far quicker, etc.

  4. Re:YAY !! 1952 ALL OVER AGAIN !! by moniker127 · · Score: 4, Insightful

    They haven't had any failures since the advent of the falcon 9 rocket. The first three falcon launches failed, and if the fourth hadn't worked, spaceX would've folded. Luckily, the fourth did work, and they learned a lot from it. (mostly that 9 > 1)

  5. Re:Whats the advantage of this tech? by Anonymous Coward · · Score: 5, Informative

    The big advantage is that when you dunk a booster the seawater gets everywhere and you have to rebuild it.

    SpaceX would rather bring it down powered, test it, then launch it again. The cost of the propellant is less than 100K per launch, its the refurbishment, and sometimes wholesale replacement of the parts that really costs a lot of money.

    More info on strategy here: http://www.popularmechanics.com/science/space/rockets/elon-musk-on-spacexs-reusable-rocket-plans-6653023

  6. This is no Space Shuttle, its better. by moniker127 · · Score: 5, Informative

    Space Shuttle:
    Payload to GTO: ~3000 kg.
    Average cost per flight: 1.5 billion (cost of shuttle program / number of launches)


    Falcon 9 rocket:
    Payload to GTO:~2000 kg
    Average cost per flight: 50m (cost of expendable rocket)


    Falcon 9 rocket with grasshopper gear:
    Payload to GTO:~1000 kg (rough estimate)
    Average cost per flight: ~200,000 (expected figure for fuel + incidentals)


    You can do the math to figure out why this is a big deal.

    1. Re:This is no Space Shuttle, its better. by milgram · · Score: 4, Insightful

      While I agree with the direction of the evolution of the programs, I don't think it is a fair comparison to define the cost of the Space Shuttle launch as the total program cost divided by the number of launches. Much of the technology and information Falcon is using is based upon the research done to achieve the Shuttle program.

    2. Re:This is no Space Shuttle, its better. by Anonymous Coward · · Score: 5, Insightful

      While the general tenor of your computation is in the right direction, you're not even closed to calculating the costs fairly. You're not being very rigorous with separating out capital vs operating expenditures. You are hitting shuttle launches with a share of all the development and infrastructure costs, but left that out for SpaceX.

      But yes, the *incremental* cost of another shuttle launch is in the 500M range, which is still pretty pricey on a $/kg to orbit.

      There are some aspects you've also sort of glossed over: Shuttle is a terrible way to get to GTO, so comparing GTO payload capacity isn't a good metric. Shuttle has the same 3000kg "downmass" capabilty, too, which I don't think F9 or GH have. If you want to bring things back for repair and refurbishment, that's a useful thing to have. Or, you could treat space like remote islands in the Aleutians.. never take anything back, and just dump the old stuff in an ever increasing pile out back for the amusement of workers on their time off.

      That said, I think cheap expendable rockets like F9 are really the way to go for the immediate future.

  7. Re:YAY !! 1952 ALL OVER AGAIN !! by crakbone · · Score: 3

    The technology was developed for the moon using ase standards. Not earth or mars. Also NASA is not great in the records dept. NASA has had to go back to museum pieces to reverse engineer equipment because document changes in design were never kept. Resulting in vast changes that were made on the fly to systems. Aswell technology has advanced and those changes need to be made.

  8. Re:YAY !! 1952 ALL OVER AGAIN !! by Anonymous Coward · · Score: 5, Insightful

    We weren't doing massive VTVL space rockets in the 50's. And maybe the armchair know-it-alls should just build their own space rockets if it's as easy as picking up a dusty set of blueprints.

    The arrogance and delusion is just astounding.

  9. Heh by ThatsNotPudding · · Score: 3, Funny

    The flight lasted 29 seconds from launch to landing, and carried a 1.8 m (6 ft) cowboy dummy to give an indication of scale."

    I was just wondering what George Bush was up to these days.

  10. Re:YAY !! 1952 ALL OVER AGAIN !! by BitZtream · · Score: 4, Informative

    Adding to your thought ...

    The 'breaking apart' was an intentional jettison of a panel to ensure any other actual issues would limit exposure to the rest of the craft. It was just like the safety blow off value on a water heater. Unacceptable tolorences were detected and the craft compensated to mitigate damage and ensure continued flight.

    The 'break apart' was by design and couldn't have been a better example of designing for failure and still winning the game.

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