back to article Leaping SpaceX GRASSHOPPER ROCKET jumps 2,500ft, lands safely

Elon Musk's Grasshooper vehicle has inched a little closer to becoming a viable VTVL (vertical takeoff, vertical landing) rocket, last week completing its highest flight to date. A video published by SpaceX on YouTube shows the ten-storey-tall jumper reaching 744 metres in altitude (a snip over 2,500 feet) before performing …

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  1. Pet Peeve

    Sometimes you just gotta say "awesome" and stop there.

    1. genghis_uk Silver badge

      Agreed - have an up-vote and I will say no more :)

  2. Gene Cash Silver badge
    Flame

    Awesome soundtrack

    Just sayin'

    1. hplasm
      Thumb Up

      Re: Awesome soundtrack

      If you watch it with the sound off, I swear you can hear the Thunderbirds theme...

      1. Peter Gathercole Silver badge

        Re: Awesome soundtrack

        It's the flame licking back up the lower part of the rocket that makes me wonder whether Derek Meddings was prescient or had a way of looking into the future (he was a model making technological genius after all).

        I always though 'it would never look like that' when I watched TB1 and TB2 land, but I was so obviously wrong!

    2. David Given

      Re: Awesome soundtrack

      I actually found it a little disconcerting the way the sound synced up with the action --- sound is *slow*, dammit, and takes a long time to get from the ground to the camera. I think that's one of the things that contributes to that wonderful air of unreality to the whole video.

      I know why they did it, of course. I'm pretty sure the sound was recorded on the ground, otherwise mostly all you'd hear would be hexacopter drone. (At least, up until that scarily close fly-past.)

      Do you think we could get them to rerecord it from a hot air balloon? They're quiet.

  3. This post has been deleted by its author

  4. Paul 185

    Did anyone else start watching this and think "wow that's a crappy CGI rocket, but at least the dust effect is pretty well done"?

    1. Anonymous Coward
      Anonymous Coward

      The whole video is clearly CGI.

      Look at how the horizon moves: perfectly smooth pan up, then as it reaches the bottom of the screen there's an instantaneous stop, zero judder, absolutely motionless. You couldn't even do that from a static tower.

      Then look at the trajectory of the rocket: absolutely perfectly vertical, not the slightest flicker of deviation and correction.

      The rotor blades are just a superimposed distractor. The cigarette-lighter flame effect was an odd choice.

      Are SpaceX really trying to claim this is genuine footage?

      1. James Hughes 1

        Are you taking the piss? Its real I'm afraid.

        This is real stuff - there was a photo posted on Twitter taken by someone off site (ie not SpaceX) of this flight.

      2. Brewster's Angle Grinder Silver badge
        Joke

        "The whole video is clearly CGI."

        And when the rocket touches down, it's not touching its shadow and the shadow has to keep on moving for a second.

        Obligatory XKCD reference [331].

        1. HMB

          @Brewster's AG

          An up vote wasn't enough. I was properly laughing out loud, cheers for the XKCD, very appropriate.

  5. ecofeco Silver badge
    Thumb Up

    Too damn cool

    Congrats again to Space X for another successful milestone.

    If I didn't know that was real, I would have sworn I was watching some very cool CG.

    Too bad the DC-X project was abandoned years ago. We could have already had this technology.

    Good for Space X to pick this up and continue its development. I sincerely wish them godspeed and good luck.

  6. DropBear

    *scratching head*

    I clearly know nothing about rocket science math, but I keep wondering how exactly that "powered descent after launch" is supposed to work, given that a launcher is supposed to boost its cargo to some seriously high speeds and heights? How much "reserved" fuel does one need to do a controlled descent from that height / speed...? Or is this going to come back down the standard way (a parachute), jettisoning it and powering up just before it touched back down...?

    1. frank ly
      Happy

      Re: *scratching head*

      I think there's some nominative determinism at work in your comment. (It's a good question too.)

    2. John Smith 19 Gold badge
      Boffin

      Re: *scratching head*

      The plan is for the firs stage to separate at Mach 6 and coast up till the air is very thin. It then does an end flip and fires 3 of its 9 engines. This has already been tried in the 1st V1.1 launch. This cancels its forward speed and (I think) gives it a bit of momentum so it "falls" back to the landing site. It's then flipped backwards so it will land engines down.

      The powered bit only starts up in (maybe) the last 1/2 mile of descent. So far it appears to be a "bang bang" approach. A short sharp 3g burst of thrust that kills momentum leaving a short fall onto the landing pad cushioned by its legs.

      1. Danny 14 Silver badge

        Re: *scratching head*

        with no organic meatbags to worry about it can be pretty sharp on the acceleration too.

        If it goes wrong you might have a big fireball at the launch site.

    3. ScissorHands

      Re: *scratching head*

      It's also a lot lighter when it comes down, so it doesn't need a comparable amount of fuel to stop as it needed for going up the hill...

    4. agentgonzo

      Re: *scratching head*

      The boosters that are being trialled here don't push the satellite all the way into orbit. They are the first stage boosters only and detach shortly after launch (like the boosters on the space shuttle). As they are travelling 'relatively' slow (but still a few machs!) they get slowed down by air resistance as they fall to earth and land and are recovered.

      The main booster that takes the rest of the satellite all the way to orbit will still be use-once disposable rockets.

      1. James Hughes 1

        Re: *scratching head*

        This is the proposed launch sequence.

        http://www.youtube.com/watch?v=sSF81yjVbJE

    5. Gary Bickford

      Re: *scratching head*

      It's been a while since I saw information about this. There is some debate but as I recall the estimate is from 10% to 30% of the fuel. The key thing is that the returning rocket is not longer carrying the weight of the second (& following) stages, most of the fuel is gone, and a big part of the fuel was spent achieving maximum velocity. That velocity can be given away by merely letting gravity take over, only maintaining the proper vertical attitude**, until the thing is coming back at a suitable rate - in fact I think it's best to wait to decelerate (perhaps just maintaining some maximum descent speed?) until the last minute* and use the remaining fuel all at once IIRC. So, taking all that into account, the fuel required to bring it back is much less.

      * the last minute - gravity is always accelerating the vehicle downwards. If you slow it down too soon, you'll have to keep burning fuel for a longer time.

      ** some reusable vehicle designs have been based on a 'flyable' first stage that would use minimal fuel to return, and land on a runway. But that has its own price in weight.

      1. b0hem1us
        Alien

        Re: *scratching head*

        The numbers seem about right. The higher you go the more fuel you will need for return though so you do have to spend more on that but it is no problem as it is not the main cost factor. There will have to be multiple burns on descent to keep the thing relatively cool and possibly stable but should not be too many. In theory you could haul ass down an then do a crazy -x*g burn just before touch down but you would need an engine that produces huge trust on demand, not an optimal solution as u use the same engine to go up.

        Keep in mind that this is all just a beginning, mostly touch down tests that have been done many times before, relatively proven stuff. Once you start dealing with the low orbit re-entry, the flip in the atmosphere, things will get rough and lot of unpredictable events can happen. The success I believe largely depends on the proper timing and very good control systems. Structural dynamics will also play important role because some of the maneuvers at such high speed will create huge amounts of stress on some parts.

        It is a good start though, that is for sure. Keep it up.

        1. David Given

          Re: *scratching head*

          The last Falcon 9 launch did some first stage tests to check out exactly this. (The first stage started to spin longitudinally, which centrifuged the fuel away from the inlets at the bottom of the tanks, and the engines went out. They're working on it.)

          It's also worth pointing out that:

          (a) the F9 first stage carries extra fuel *anyway*, in order to compensate if an engine dies on launch --- this happened on a previous flight. So a landable first stage doesn't need more fuel. It just lands on the safety margin left in the tank. If you end up using this safety margin in launch then you don't get to recover the first stage. No big deal.

          (b) falling through air soaks up an enormous amount of velocity. Instead of having to decelerate from 7000 km/h at mach 6, you let the air do it for you; when you get close to the ground you're only moving at a few hundred km/h. This saves an incredible amount of fuel.

          Regarding (b), go get the eval copy of Kerbal Space Program and try it out for yourself.

          1. annodomini2

            Re: *scratching head*

            They tried reigniting the second stage as well, but stopped due to a problem.

            They're looking at recovering both stages.

  7. frank ly

    re. the observing video camera

    I just watched the video (I had to disable AdBlock .....shudders). Is that one of the arms of a quadracopter, or similar remote controlled device, that you can see towards the peak of the climb? I suppose it would be cheaper than using a helicopter.

    1. Richard 12 Silver badge

      Re: re. the observing video camera

      Yes it is. You can see two of the rotors at one point.

      Guessing hexaopter, but harder to tell

      It's the only sane way to get this kind of footage - no helicopter pilot is ever going to agree to fly that close to an operating rocket!

      I think some of the apparent CG-ness comes because the camera gimbal is too good!

      1. Shades

        Re: re. the observing video camera

        Richard 12 wrote:

        "I think some of the apparent CG-ness comes because the camera gimbal is too good!"
        I'm fairly certain the footage has also been additionally stabilised after shooting. A clue is the way the horizon seems almost locked in place yet one of the hexacopters rotors drops into view then goes back out of frame... Thats either post stabilised footage or one bendy rotor arm! Further still, when the camera tilts up, past the horizon, and the rotor comes completely into view the rocket then almost seems locked into place while the rotor is all over the shop, again a classic sign of post stabilised footage.

        1. Richard 12 Silver badge

          Re: re. the observing video camera

          For this kind of shoot, you generally mount the camera on its own stabilised gimbal.

          This is the only way to ensure the camera stays pointed in the chosen direction while the 'copter moves around to manoeuvre and stabilise the overall frame.

          A two axis, tilt and roll gimbal covers the stabilisation motions a 'copter will do, then pan by rotating the whole airframe.

      2. I ain't Spartacus Gold badge
        Happy

        Re: re. the observing video camera

        It's the only sane way to get this kind of footage - no helicopter pilot is ever going to agree to fly that close to an operating rocket!

        Well they should just man up! What a bunch of big-girls'-blouses!

        There's always the tactic used when they made 'The Battle of Britain'. They had a B17 as their main camera plane, because it was about the same speed as the fighters, and had lots of places to stick cameras.

        But obviously too dangerous for shots of fighters coming at the camera head-on, or the really close dog-fighting stuff. So their solution was to get a helicopter, and rig a cradle on a 300 foot wire. Then their looniest cameraman sat in that, with a camera rigged on some kind of gimbal mounting and let planes fly almost straight at him. Balls of steel. Not sure what it says for his brains though...

    2. Simulacra75
      Holmes

      Re: re. the observing video camera

      It is a hexacopter. Clue is in the title of the youtube vid.......

    3. Anonymous Coward
      Anonymous Coward

      Re: re. the observing video camera

      > I just watched the video (I had to disable AdBlock .....shudders).

      I use AdBlock too, but it doesn't block TheyTube by default. It just adds a little "Block" tab next to the Flash object, should I want to block that content (it does block Flash ads, btw). I don't recall modifying the default configuration, btw.

      > I suppose it would be cheaper than using a helicopter.

      And safer!

  8. ThatGuy

    Can someone explain...

    ..why SpaceX did not get the "most innovative company" award?

    1. Yag

      Re: Can someone explain...

      Because they're not innovative enough where it counts (according to the jury) : PR, marketing and fiscal avoidance.

    2. ecofeco Silver badge

      Re: Can someone explain...

      HA! I made the same comment to that article as well!

    3. Danny 14 Silver badge

      Re: Can someone explain...

      it is primarily based off Mcdonnell D DC-X though and since that had a contract to scaled composites they are simply reexamining work done by a bigger team. Sure they are making it work better but not innovating (it is fantastic work nontheless)

      1. John Smith 19 Gold badge

        Re: Can someone explain...

        "it is primarily based off Mcdonnell D DC-X though and since that had a contract to scaled composites they are simply reexamining work done by a bigger team. Sure they are making it work better but not innovating (it is fantastic work nontheless)"

        Wrong.

        Blue Origin (or rather what little they release) is doing some work based on the DC-X.

        DC-x sidesteps the control problems by using a wide/squat lifting capsule shape. This is much simpler to control and make (relatively) rigid. OTOH normal rocket stages have high aspect ratios and are "floppy." The control problem has AFAIK never been thoroughly worked out, which is what they are doing.

  9. Crisp

    Well it works in Kerbal Space Program.

    What took them so long?

    1. DrStrangeLug

      Clearly...

      Clearly they used mechjeb. Cheats!

      1. Crisp

        Re: Mechjeb

        Mechjeb isn't cheating!

        It just makes things slightly easier....

    2. Irongut

      Re: Well it works in Kerbal Space Program.

      It looked a lot like they used KSP to create that footage.

      jk Great job again Space-X!

  10. Nya

    FAB!

    They have to paint one up to look like Thunderbird 1.

    1. ecofeco Silver badge

      Re: FAB!

      Damn! That's genius! (seriously. wished I thought of that)

    2. TheProf Silver badge
      Mushroom

      Re: FAB!

      Or TB3. I (think I) remember seeing TB3 return to base. Alan has to get the craft back through the opening in the torus-shaped building. At least Scott had a swimming pool he could dump on the flaming wreckage should he get the landing wrong.

      1. Peter Gathercole Silver badge

        Re: FAB!

        If you remember, the swimming pool moved under the patio when TB1 took off or landed, so he did not have that option.

        The torus shaped building was called 'the roundhouse'. Quite what you use such an unusually shaped building for, I don't know.

        I'm sure that the few times they show the clip of TB3 landing, they've even managed to collect the smoke again. That's really environmentally aware!

        1. Tokoloshe

          Re: FAB!

          "The torus shaped building was called 'the roundhouse'. Quite what you use such an unusually shaped building for, I don't know."

          The Fusion Reactor (probably).

          Perhaps Musk's eggheads can get to work on that unsolved problem after completing the full set of TB craft.

  11. Anonymous Coward
    Anonymous Coward

    That cameraman ...

    .. should be shot.

    Otherwise, yes .. Awesome!

    That noise!!!!

    1. James Hughes 1

      Re: That cameraman ...

      You do realise that the cameraman was one the ground controlling a remote hexacopter? Seems to me that he did a pretty good job.

  12. Robert E A Harvey

    extra flame

    What is the extra, non-thrusting, flame coming out of the side?

    1. Steven Raith

      Re: extra flame

      Think it's part of the control system - presumably it's adjusting position by dropping power to certain parts of the rocket engine, and those flames are the excess fuel being dumped and burned in a non-power generating method?

      That's what I've assumed, anyway - anyone know any better? As noted above, they don't seem to be especially powerful (compared to the main engines) so just dumping fuel before it hits the main engine units to 'dial them back' and allow attitude control?

      1. James Hughes 1

        Re: extra flame

        No, it's the exhaust from the turbopump I believe. Quite a flamy one!

      2. Andy Gates

        Re: extra flame

        It's the pump exhaust - new on the 1D. The previous engine incorporated it into the main burn, for a tad more power and a lots more engineering. The 1D is geared to mass production, so the complexity was dropped and you get that wiffly flame at low speeds as a result.

        1. Steven Raith
          Thumb Up

          Re: extra flame

          Awsume - so for simplicity, and presumably, Rule Of Cool.

          Nice.

          Steven R

        2. Robert E A Harvey

          @Andy Gates

          Thanks for the lucid explanation.

    2. Anonymous Coward
      Anonymous Coward

      Re: extra flame

      > What is the extra, non-thrusting, flame coming out of the side?

      Oh, that's just for added coolness. :-)

      1. hplasm
        Coat

        Re: extra flame

        "Oh, that's just for added coolness. :-)"

        Extra heat, shurely...

        1. BorkedAgain

          Re: extra flame

          I sort of assumed it was the struts burning... :)

          Seriously cool.

  13. Anonymous Coward
    Anonymous Coward

    Words fail me...

    ...but I will try - if that was real footage then I am totally flabbergasted and gob-smacked - really fantastic!!!

  14. Parax

    Hexacopter choreographer

    Am I the only one who finds the hexacopter footage slightly disappointing?

    Don't get me wrong I love it, but It seems like they are just turning up and shooting what they can.. which is still good, but could be much better. I feel they are not making the most of GPS waypoints. They (someone at spacex) should know exactly where the Grasshopper will be, so the hexacopter could be preprogrammed with a GPS sequence (using manual waypoint advance for timings if preferred) It would be superb to fly around the hovering grass hopper, and even drop down to the pad with it. (I'm not sure the hexacopter could match grasshoppers climb rate though...)

    I do agree with Elon when he says: always look for what you can do better.

    1. nematoad Silver badge

      Re: Hexacopter choreographer

      "Am I the only one who finds the hexacopter footage slightly disappointing?"

      Yes, probably.

      It looks like the SpaceX team are concentrating on the rather more important task of getting the booster stage to return to its launch pad.

      I suppose that they could always sub-contract the video stuff to someone else. Pixar or someone like that.

      1. James Hughes 1

        Re: Hexacopter choreographer

        Yes, definitely.

        I think that may be the closest ever footage of a rocket in flight from another in flight vehicle.

    2. kyza

      Re: Hexacopter choreographer

      You should probably offer your services to SpaceX as a volunteer hexacopter programmer or something.

      1. Richard 12 Silver badge

        Re: Hexacopter choreographer

        I would genuinely love to do that.

        Unfortunately, I'm based in the UK which means I can't afford the commute.

  15. phil dude
    Thumb Up

    speechless...

    I turned off the sound and had chills running down my back...truly awesome.

    P.

    PS I think I might have to get myself one of those 'copters.....

    1. James Hughes 1

      Re: speechless...

      I dunno - I had the sound on - with decent bass it's, well, even more truly awesome.

  16. Anonymous Coward
    Anonymous Coward

    Too bad space doesn't start at 2500 feet.

  17. Anonymous Coward
    Anonymous Coward

    Try doing this kind of launch...

    ... yourself! It's not easy. In Kerbal Space Program you can build some rockets that are similar though. :)

    http://youtu.be/_cslH4cnvDU?t=1m25s

    Will Vulture Labs ever do similar?

  18. John Smith 19 Gold badge
    Meh

    Musk stated the booster stage can has a mass ratio of 30 to 1

    While F9R won't be quite that good it will be very light given it's a) burnt off most of it's fuel IE over 90% of the stage takeoff mass and b) No longer have a 2nd stage & payload sitting on it.

    That' means it needs a very small amount of propellant coming down compared to what it used going up.

  19. Donald Becker

    I'm still trying to figure out if that was 1950s fake or 1960s fake.

    I'm leaning towards 1950s with colorization... the tacky flickering flame effect was used before the public knew what real rockets looked like.

    1. James Hughes 1

      Or, and here the thing, perhaps it's 2013 real!

  20. Will Godfrey Silver badge

    Really impressed with this! No matter what the cynics mutter.

  21. starsilk

    not true. Merlin 1C (the previous engine) also dumped the turbopump exhaust overboard. the new Merlin 1D-VAC (vacuum optimized version, for upper stages, not what you're seeing here) is the only Merlin that dumps the turbopump exhaust through the engine bell, because it improves performance slightly at the expense of cost and weight.

    1. Iain McClatchie

      So does 1d-VAC require cold gas thrust for roll control? Seems like that would need a bunch more mass, and add risk, as they've had two different unplanned events with too much roll - one of the early Falcon 1 upper stages was lost due to excessive roll, and this latest launch's lower stage rolled too much as they tried to recover it.

  22. Herby

    It could be (but probably isn't)...

    A shot of the rocket going up for a while, then a nice reverse of the movie. You can be sure it goes back to the correct place when you go forward for a while (until it disappears) then run the movie in reverse.

    No, it doesn't look like that, as the up shot is quite different from the down shot, but you never know.

    1. James Hughes 1

      Re: It could be (but probably isn't)...

      WTF? Did you actually watch the video? Or any of the previous videos of the grasshopper in flight? They land where they took off from! It's not rocket science...oh, hold on....

      This sort of pinpoint landing is pretty easy once you have the control systems in place. Which they do. Also watch Armadillo aerospace videos, or Masten Space systems demonstrating exactly the same thing (but on a smaller scale)

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