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Space Transportation Science Technology

SpaceX's Grasshopper VTVL Finally Jumps Its Own Height 111

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."
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SpaceX's Grasshopper VTVL Finally Jumps Its Own Height

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  • Ad astra (Score:2, Funny)

    by 14erCleaner ( 745600 )
    per dot-com bubble!
  • 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?

    • by dreamchaser ( 49529 ) on Thursday December 27, 2012 @10:53AM (#42403651) Homepage Journal

      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.

      • SpaceX has tried this. The problem is landing in the water is violent. They kept destroying their rockets. The Shuttle SRB's can do it only because they are made of about 1/2" thick high strength steel. Even then when they built one for ARES IX test it went higher and landed harder and this was the result.

        http://t2.gstatic.com/images?q=tbn:ANd9GcSkDV1l2N0CFkWZmpOxrEyo09JBWK34zbjSC6JRI55c0zNyGM8ht4rdbnvOJQ [gstatic.com]

        • by tragedy ( 27079 )

          Also, the shuttle's SRB's had a little trouble with the O-rings in their tang and clevis joins fitting properly. This may have been partly due to the mild deformation of the SRB's occurring during splashdown. The problem was mostly due to other design causes, but the deformation of the tanks was part of it. As a consequence of this problem and other factors, a jet of flame ended up spurting out of one of the SRB's during a launch and cutting into the liquid booster during Challenger's last launch. Also, for

      • by Anonymous Coward

        sea water turns the module into scrap metal even if landing doesnt break it mechanically, everyone drops rocket stages into ocean, they are not usable after that.
        the thing is that even though rockets look all big and sturdy they are not, they are really very thin walled and fragile, only meant to endure stresses in one direction - vertical, add salt water damages to that and you might just as well build a new rocket after splashdown.
        this VTOL tech surely wastes a lot of fuel and thus reduces usable payload

    • I don't see the point of reusing 747s all the time? Why don't we just make new ones for every flight? Everyone knows that its much more fun to fly in a brand new plane.
    • by Anonymous Coward on Thursday December 27, 2012 @10:59AM (#42403687)

      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

    • by Anonymous Coward

      Fuel is the least inefficient way to do it. You've already got an engine there, so why not use it again? You've already got fuel tanks, so why not just a keep a little for descent? Why go back to the drawing board to invent wings, or other massive stuff?

    • by Anonymous Coward

      You need to slow down from launch speeds to even consider deploying a shute. Also even with such, landing on the ground is too high an impact speed to make the vehicle reusable, and sea landings introduce corrosion costs. Look at the shuttle boosters for ex, and ou have to factor in the cost of retrieval.

      This is a long term investment on the pa rt of spaceX. We have been talking about reusable launch vehicles for decades, and it has never been achieved in any meaningful way to date. Yes, the shuttle air

    • by Megane ( 129182 )

      It's not much of a waste of fuel because... it's mostly empty after stage separation! So it has maybe 5% (number pulled out of my urectum) reserve fuel left and no cargo. It takes a lot less fuel to bring an empty tank stage down with a powered descent than it would the whole vehicle assembly at launch. And then there's that little problem about sea water being so nasty when it gets into stuff.

      And then on top of all that, it's frickin' cool, too.

    • You’re making the assumption that it is a bigger waste to carry excess fuel then it is to haul wings into space. I am not sure if that is true so I would like to see your calculations.

    • by tgd ( 2822 )

      I really can't see one.

      Its not rocket science.

      Wait, yes it is. That might be your problem.

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      No advantage at all unless you are on the surface of Luna or Mars and wish return home to your loved ones.

  • by moniker127 ( 1290002 ) on Thursday December 27, 2012 @11:23AM (#42403823)
    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.
    • by milgram ( 104453 ) on Thursday December 27, 2012 @11:34AM (#42403919)

      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.

      • Much of the technology and information Falcon is using is based upon the research done to achieve the Shuttle program.

        Like what? *crickets chirping*

        • The *complete absence* of solid rocket boosters in SpaceX's plans is a direct result of research done to achieve the Shuttle program. No way in hell were they going through that ordeal again.
    • Don't forget to include the following for the Shuttle.
      7 people to LEO for 2 weeks
      AND
      50,000 lbs of payload
      AND
      Dock and service a Satellite
      AND
      bring back 30,000 lbs of payload
      AND
      Land on runway with 1,000 miles cross range capability

      • And that 1000-mile cross range capability is useful for space travel... how?

        • And that 1000-mile cross range capability is useful for space travel... how?

          Landing away from the weather that would otherwise prevent you from landing before your life support ran out?

        • What is the cross range capability of grasshopper? If you're going to pretend the shuttles cross range capability is useless, then grasshopper is even more so.

          • A parking orbit means practically indefinite cross-range capability, so long as the power systems last.

          • How about just waiting for the next orbit and then de-orbiting? Cross range is a military requirement and not necessary for civilian launches.
        • As you orbit the earth rotates underneath you. Having a large cross range allows you multiple landing attempts at the same place on earth in consecutive orbits.

    • by Anonymous Coward on Thursday December 27, 2012 @11:41AM (#42403975)

      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.

      • SpaceX does provide 'some' cargo return capability. http://www.spacex.com/crs1.php [spacex.com]

        Of course it is nothing compared to space shuttle, but when is the last time that a space shuttle bring back anything huge? Or, has it ever done so?

        • The main unclassified use for the Shuttle's cargo return ability was Spacelab [wikipedia.org] missions.

        • Of course it is nothing compared to space shuttle, but when is the last time that a space shuttle bring back anything huge? Or, has it ever done so?

          LDEF, Spacehab (multiple times), Spacelab (multiple times), MPLM (multiple times), the Hubble handling fixture (six times) and maintenance equipment (five times)....

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

        Actually, the incremental cost of a Shuttle flight (that is, the direct costs to add a flight to the manifest) was down around $100-150M depending on who you ask. The annual cost per flight did range around $500M post Challenger, but that's because annual costs were dominated by massive fixed infrastructure costs that had to be paid regardless of how many flights were on the manif

        • For example, much of the water the Shuttle delivered was a byproduct of it's fuel cells and was thus essentially free.

          As long as you ignore the billion dollar cost of launching the Shuttle each time, anyway.

          You could send a lot of water into LEO for the cost of a single Shuttle launch.

          • For example, much of the water the Shuttle delivered was a byproduct of it's fuel cells and was thus essentially free.

            As long as you ignore the billion dollar cost of launching the Shuttle each time, anyway.

            If the cost was relevant, you'd have a point. But in your haste to make a smart ass comment (and thus expose your ignorance) you ignore than fact that the Shuttle was going to the ISS (in this example) anyways.

            • My ignorance? The whole post was based on a logical fallacy. "Hey, we were in the neighborhood, anyway." Um, no... you weren't. The Shuttle didn't just happen by the ISS and say "we were going to vent this water, anyway". The Shuttle was sent to ISS to deliver... water... food... parts, etc. You could just as easily say delivery of the parts were free, because they were going to have to come bring water, so why not bring the parts.

              Same thing with the argument about fixed vs marginal costs for the prog

              • Same thing with the argument about fixed vs marginal costs for the program as a whole. It's a logical fallacy to say "it doesn't really cost $500 million per launch, because most of it is fixed". OH YES IT DOES cost $500 million per launch, because the alternative is shutting the program down and slashing those fixed costs to zero.

                In your haste and ignorance, you fail to realize the existence of a third alternative - to fly *more* per year and amortize the fixed costs over a larger number of flights and thu

    • For what I gather, spaceX is mostly made up of ex-NASA people. From that it follows that spaceX probably did not invent the wheel, but simply copied and improved the one invented (and paid for) by NASA.

      So, while spaceX stuff is better than the NASA stuff, it is not because spaceX is somehow hugely better at what they do. It is just that NASA paid for the initial development of space technology, and folded soon after delivering some proof-of-concept stuff. SpaceX was then simply able to pick up where NASA le

      • For what I gather, spaceX is mostly made up of ex-NASA people. From that it follows that spaceX probably did not invent the wheel, but simply copied and improved the one invented (and paid for) by NASA.

        I expect that it's more of a case of "NASA won't let us build the cool vehicles we want to build, it makes us build all this expensive crap, and we get to do it for maybe three vehicles before we end up dead from old age; hey! Let's go work for this billionaire who actually has a vision of the future he wants to build, instead of these politicians and bureaucrats who don't get that roller coaster feel in their stomach every time someone plays the Kennedy moon speech..."

        Personally, I'd rather work for someo

    • To be fair, a LEO-to-LEO comparison is probably more apt than GTO-to-GTO capacity. Even so, the Falcon still wins easily, even without being reusable.

      The big question-mark is how much the new reusability features will end up costing in terms of performance and payload. If they lose more than about 20% of current capacity on the F9, it probably won't be able to loft a standard Dragon capsule. They'll either have to develop a smaller Dragon or use Falcon Heavy instead.

      • The Falcon Heavy has two side boosters, which detach after liftoff, presumably grasshopper gear will be fitted to these, and they will each vertically land, while the main body of the falcon heavy continues on.
        • Yes, that's what I was trying to say. (A customer came into my shop as I was writing that, so I had to cut it short.) A Falcon Heavy (even a reusable one) would have plenty of excess capacity for a standard Dragon capsule. And the same economies of scale and reusability would all still apply in this case. Yes, fuel costs might be $500~600k per launch instead of $200k, but that's still "dirt cheap" for a ride to LEO, especially if you can split that cost between 4~6 passengers.

          In any case reusable rockets wi

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

      By your logic, we can replace semi-trailers and concrete trucks, and ambulances, and every other form of automotive transport - with motor scooters. After all, they're cheaper and they get great gas mileage.

      Seriously, as I've said here before (many, many times), it's not all about cost. You also have to consider capability, what are you getting for your money? Nobody confuses a subcompact with a panel van, or a teaspoon with a frying pan...

      • The space shuttle was ultimately a vehicle for delivering crew and cargo to orbit.
        This task is accomplished for less money by the falcon rockets.
        Granted, If you put a ping pong table on the shuttle, its ping pong capabilities would be incomparable to the falcon rockets.
        • The space shuttle was ultimately a vehicle for delivering crew and cargo to orbit. This task is accomplished for less money by the falcon rockets.

          In other words, you just repeat what you said the first time - without addressing the issues I raised in my original reply.

          Not to mention, as I discuss in another post, it's not clear at all that the Falcon is cheaper... when you consider how many Falcon flights it takes to replace a single Shuttle flight.

          • It is all about cost. How inexpensively can you get people and cargo to orbit? That is the only question I'm concerned with.
            • I can get them to orbit FAR cheaper than SpaceX or NASA. Of course, they won't be able to do a thing when they get there as they'll be dead or otherwise damaged beyond usefulness. You can design a gun capable of lobbing things into space, the Gs from initial acceleration would destroy your people and cargo however.

              As was said, cost is not the only issue.

              • Getting the remains of things to orbit is not getting things to orbit. There is a difference in pointing out valid problems with the premise of cost as the only issue, and trolling.
            • In other words, you're not only stupid and ignorant - you're willing so.

              Sad.

    • Yes, if you ignore everything SpaceX got out of the Shuttle program then sure, the numbers look great.

      The didn't invent rocketry, they've improved on research done before them by NASA and things like the Shuttle program.

      Admittedly, NASA and the Shuttle program didn't invent it either ... but a metric fuckton of shit used today to make Falcon work WAS invented to make the Shuttle program work.

      Thats not even to mention that you included ALL R&D costs in the shuttle, but none in SpaceX.

  • ...is maintaining stability while exiting and then re-entering the ground-effect region.

  • Heh (Score:4, Funny)

    by ThatsNotPudding ( 1045640 ) on Thursday December 27, 2012 @02:29PM (#42405237)

    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.

  • Once upon a time a junkman had a dream

    http://en.wikipedia.org/wiki/Salvage_1 [wikipedia.org]

    and pics of the spaceship http://www.webcitation.org/query?url=http://www.geocities.com/CapeCanaveral/Launchpad/9782/salestes.html&date=2009-10-25+06:41:49 [webcitation.org] [webcitation.org]

    I loved that show as a kid now I just need a cement mixer, fuel tanker, and some recycled tyres

  • Whenever anything related to space is posted, the NASA bashing crew crawls out from their cave, hooting and slinging shit like apes in a zoo cage. I wonder why this never seems to bore them. It bores me.

    NASA has the best record for space exploration of any organization in the world. If you give them sufficient resources and don't mix in politics they usually succeed beyond expectations.

    The Shuttle is the poster child for political meddling. The mandate from Congress was that the military and NASA would us

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