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View From The Barge as Falcon 1st Stage Lands

By Keith Cowing
NASA Watch
April 16, 2015
Filed under

NASA Watch founder, Explorers Club Fellow, ex-NASA, Away Teams, Journalist, Space & Astrobiology, Lapsed climber.

117 responses to “View From The Barge as Falcon 1st Stage Lands”

  1. Yale S says:
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    I did something like that last winter walking on an icy sidewalk, but without the awesome fireball.

  2. Shaw_Bob says:
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    Oh, well done SpaceX! Nearly there!

  3. JadedObs says:
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    Translation – it came in too fast!

    • Yale S says:
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      It was zero velocity in the vertical direction. Due to some problem in the controls it had a horizontal component and tipped over.

  4. DTARS says:
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    Wouldn’t it be nice if the barge could grab the legs so the rocket couldnt blow over in wind or crooked landing. You know like if the deck was an electro magnet or something. How big would an on board generator have to be to hold that sucker down??

    Why do these boosters only have 4 legs??? Don’t they need 5 to have leg out capability???
    I carry a spare tire in my to trunk in case a tire fails. Wouldn’t you want a spare leg on your 30 million plus reusable booster???

    Isn’t 5 leg reusable boosters just common sense???

    • Bernardo de la Paz says:
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      No. They already have serious mass fraction problems with their recovery system. Adding an extra landing leg would just make it worse, with little added benefit.
      Besides, this obviously wasn’t a landing gear problem.

      • Todd Austin says:
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        And take a look at Falcon before launch. I doubt you could find space in the circumference of the F9 to put another leg.

    • david says:
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      All you need is 3 legs for a stool, just got to put it on the floor and sit on it right and no problem lol

      Great video. Falcon spent stage just needs some wings and just glide back to the SLF. #shuttleflybackbooster

      If this vertical landing is required, make it piloted. Dude Perfect can do it and sink a basket on the barge.

      https://youtu.be/TziuG5LtEWY

      I am serious actually, look at the CG shift required to make much lower speed landings.

    • rb1957 says:
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      I too was wondering about the “hold down” mechanism; helicopters often have a harpoon, maybe it’s like their automatic docking at ISS (line up on some features, activate something to engage).
      4 legs is a minimum number, personally i’d’ve used 6 … yes, it’d be a little heavier, but … maybe they under-estimated the load that can be applied so the legs may need to be beefed up …

    • Mark_Flagler says:
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      Good point, DTARS, I suggested five legs years ago. There are five legs on office chairs for a reason–even a four-leg arrangement can be unstable, and if you lose one of four, you lose the whole booster. And it goes without saying that a booster landing is a much more dynamic situation than encountered by the average office chair.
      I would like to see five lighter legs replace the four heavier ones now in use.

  5. Bernardo de la Paz says:
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    I think you mean: “View from the barge as Falcon 1st stage crashes.”

    • objose says:
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      You noticed that as well BP. Headline bias.

      • kcowing says:
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        Watch the video. It landed. Then it fell over and blew up.

        • enginear says:
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          That is taking the definition of landing pretty wide. I looked at the video multiple times and at no point did the vehicle appear to be perpendicular to the deck after making contact. Unless all four legs make secure contact (as designed, not in parts) with the surface i don’t think you can call it a landing.
          How about “View from the barge as Falcon 1 stage crash lands” 🙂

          • Yale S says:
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            What about describing it as a Schrödinger’s Landing? Very meta…

          • Steve Pemberton says:
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            Using aircraft as a comparison, the word crash can be used two ways. It is often used as an overall description of an incident. It is also used to describe the specific moment in an incident when the vehicle breaks up.

            Runway overruns are a good example. Here are a few excerpts from a Wikipedia article that I selected at random about the Air France 358 overrun at Toronto Pearson in August 2005:

            “The crash of Air France Flight 358 was….”

            “… just after landing at Toronto Pearson International Airport ….”

            “…. it crashed into nearby Etobicoke Creek…”

            Most overruns are caused by a problem during the landing, such as landing long, or with too much speed, or failing to set the spoilers to auto deploy. So I guess you could call it a crash landing, but I wouldn’t. To me a crash landing is when the landing impact itself causes the breakup.

            Certainly no one is saying that the Falcon stage landed successfully, but after watching the video I agree with Keith that it did land. I realize this isn’t horseshoes or hand grenades but it sure looks like this was really close to being a successful landing.

        • Lewis says:
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          Impacted at an angle, gear broke, fell over, blew up… kind of like a crash. Could be a landing to professionals.

        • objose says:
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          Then “View From The Barge as Falcon 1 Stage Falls over and Blows up” would have been a more accurate headline? When are you going to get those damn emoticons activated on this site. 🙂

    • kcowing says:
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      No. It landed. Then it fell over and blew up.

      • Bernardo de la Paz says:
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        Well, at no point in the video does it reach the landing point in a stable orientation with no residual motion. I would call that a crash, not a landing. When an airplane hits the runway hard enough to collapse the landing gear or fast enough to run off the end of the runway, we still say that it crashed…

        No matter though, definitely count me in the camp that thinks it looks like they are getting close and will soon have it worked out.

        On the other hand, however, I am not a controls expert and tend to be naively optimistic about such things. There are some folks who think the road ahead may not be so easy: https://www.linkedin.com/pu

        • Steve Pemberton says:
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          “airplane hits the runway hard enough to collapse the landing gear”

          Yes I would call that a crash. Although in the case of the Falcon it did not hit hard and collapse the landing gear (not that you said it did) instead it appears to have landed on maybe two legs, held steady momentarily, then started tipping over, and the sideways stress on the landing gear caused it to either detach, bend or break (pure speculation since the smoke obscures the view).

          Back to airplane examples, if a wheel on one side would not deploy, and the pilot had to land on one wheel and hold the wing up as long as possible before setting it down, which usually works out fine with minimal damage, but let’s say that it then skidded off the runway and broke up. I would say that it landed on one wheel and then went off the runway and crashed.

          I realize we are into semantics here, but after all it is a headline, which by nature is going to be somewhat cryptic and require reading the article (or in this case watching the video) to fully understand the situation which the headline is calling attention to. And the airliner comparisons (which I also made in an earlier post) are not perfect because airliners land every day without incident, and any landing which results in damage or injury will naturally be referred to in the extreme negative. However we are discussing a novel attempt to do something that many have said (and continue to say) is impossible, so the semantics are not quite the same in my opinion.

  6. John Thomas says:
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    Looks like at least one leg failed.

    • Hug Doug ✓ᵛᵉʳᶦᶠᶦᵉᵈ says:
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      I very much suspect that the stresses put on the legs were far outside their design parameters.

      • Steve Pemberton says:
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        It looks to me like the overall amount of force was nominal, but due to not being vertical it would have been disproportionate on one or two legs, especially as it started to tip over, and the force on those legs would have been from a different direction than they were designed for. The leg failure actually could have been at the attachment point, not the leg breaking or bending.

  7. Michael Mahar says:
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    I’ve done some dynamic control work. The problem here seems to be with the control thrusters firing for either too long or too much thrust. This sets up an oscillation that keeps getting bigger and bigger. I would expect a rocket that was just about to land to be almost completely vertical and not swing side to side like that.
    If you look at the video, it appears that the booster was doing quite nicely a couple of hundred feet up and then starts to rock a bit. The correction thrusts over compensated and then did it again and again. It’s pretty surprising that it did as well as it did considering that it was at a 15-20 degree angle only a few booster lengths up.
    There are very many reasons that can cause the control thrusts to be wrong from sub optimal constants in the software to a valve in the thruster control that gives you too much power.
    When I was doing robotics, this sort of behavior was an indication that we were close to getting things right.

    • Daniel Woodard says:
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      Musk mentioned a sticking valve.

      • John Thomas says:
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        But that mention has now been removed from Twitter.

        • Hug Doug ✓ᵛᵉʳᶦᶠᶦᵉᵈ says:
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          Since it was deleted, I’d take it to be a preliminary assessment, rather than the final word on the matter.

          • Todd Austin says:
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            Musk tens to clean up his chatty conversational tweets after the fact. The fact that these were pulled does not imply anything in particular.

          • Terry Stetler says:
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            Or something their ITAR lawyers got twitchy about.

          • Hug Doug ✓ᵛᵉʳᶦᶠᶦᵉᵈ says:
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            Well… That could be a consideration… But there wasn’t that much detail in it.

        • Daniel Woodard says:
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          Close to touchdown the vertical velocity is too low for the grid fins to be effective so there is no way to apply lateral force to the top of the booster. Consequently there are limits to the degree of wind shear and lateral drift that the control system can compensate for. The legs don’t give a lot of stability and even a slight rotational velocity in pitch or yaw would tip it over, as seen here. These factors are always going to be harder to control at sea. Although a landing should be possible in calm conditions it is never going to be practical in even moderate swells absent expensive mods to the booster and/or barge. It’s not even stable after landing if the barge is rolling more than a few degrees, hence the plan to weld the feet to the deck. The problem is the touchdown, not the descent guidance. A simple concrete pad on land could provide a larger touchdown area to accommodate lateral drift, windbreaks, and won’t be damaged by a tipover/explosion any more than the barge. It’s time to land on … land.

          • Michael Mahar says:
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            If you look at the videos, you will see jets coming off the top of the booster as it tries to right itself. There is some lateral control at the top.
            The booster doesn’t seem to be rocking much until the legs come out. Then it starts to tilt. That could for several reasons. The booster was off target and trying to correct. The legs caught the wind or came out in such a was as to start oscillating. Or, its something that is buried in the telemetry that we can’t see.

            I don’t think that the rocking of the barge is a significant factor. It seems pretty stable in the videos compared to the rocking of the booster.

        • Terry Stetler says:
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          And this evening Musk confirmed on Twitter that the sticking valve was the cause.

    • John Thomas says:
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      I’m not sure it’s the control thruster but rather the main engine pointing control. Looks like a control loop problem. Could be related to winds hitting the barge and coming up at the rocket, sort of like a ground effect. I would think you would have a similar problem even on land.

      • Yale S says:
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        Musk:
        “Cause of hard rocket landing confirmed as due to slower than expected throttle valve response. Next attempt in 2 months.”

        The lag between command and response led to overcompensation and the fatal horizontal motion.

    • Michael Spencer says:
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      Do any of the smart people around here have an idea of the mass of that thing? How much does an empty (nearly) stage actually weigh, anyway?

      • Duncan Law-Green says:
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        I’ve seen estimated figures in the range of 18-25 tons.

        • DTARS says:
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          With it swinging on an angle like that, at the last minute, I’m wondering how much fuel was in the tank and how big/tall their baffles are? Seems to me that fuel movement could have played a factor in this one tipping over?

    • Robert van de Walle says:
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      Hey Mr. Dynamic Control 😉

      When I watch the other video https://www.youtube.com/wat… at full screen, I see that the rocking of the barge and the rocking of the rocket seem to be coupled. There’s even a small bit of delay between the barge motion and the rocket’s response (if that is in fact what is happening). I recall reading, perhaps over at Spaceflight Insider, that the barge relays its position to the rocket. Is it likely that what happened is the hand-off from one set of guidance telemetry to another, as well as sloppy code for finding vertical, caused the large scale redirections that we see?

      • PsiSquared says:
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        See Terry Stetler’s comment above about Musk confirming that the problem was a sticky valve.

  8. Dewey Vanderhoff says:
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    Immediately before seeing this astounding video, I watched the new trailer for ” Star Wars: the Force Awakens”.

    Seamless segue…

  9. RocketScientist327 says:
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    If this on the center pad at Landing Complex 13, it is my opinion, that this lands successfully. This video is very convincing that all of the hard work put in by the team at SpaceX is paying off.

    Really quickly I would like to thank every congressman, senator, and staffer who took the time to learn and support COTS and CCDev projects. Your tough votes, especially in 2011 and 2012 are now bearing fruit.

    We are all winners.

  10. Steve Pemberton says:
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    Why, do the computers need more time to think? Watching just the vertical velocity it stops on a dime. Burning more fuel, even if it’s available, would perhaps make us less nervous watching it, but what if there is no actual benefit? Reminds me of watching nature programs where things happen so fast they have to use high speed cameras to slow it down enough for us to see it. Finely tuned systems in nature and in electronics are much faster than humans. The same seems to be proving true with powered rocket landings which are starting to look much different than all of the sci-fi movies we have watched. It takes some getting used to.

    Of course when there are failures the natural reaction is to believe that it is at least partly due to “coming in too fast”. But I don’t think there is any evidence of that on this landing or the last one.

    • John Thomas says:
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      Could be related to wind turbulence near the barge (wind hitting the barge and coming up?). I would think you would have that problem even on land. They may need to slow the descent at the ground to allow the control loops time to analyze the varying wind and correct for it.

      • Daniel Woodard says:
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        Agree but on land the pad could be shielded from wind by trees or artificial barriers, and wind shear sensors could be mounted around the pad to provide guidance cues. Also the ground would not be moving (in all six axes!) as is unavoidable on the barge.

        • Paul451 says:
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          but on land the pad could be shielded from wind by trees or artificial barriers

          Could be, but won’t be. Look at any aerial image of the new pads.

  11. Steve Pemberton says:
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    From what we are hearing there was a technical problem, not inadequate rate control. Jordan Spieth (recent Masters champion) has tremendous control of his golf swing. If he suddenly had a muscle cramp that caused him to hook every shot, his trainer would not tell him to concentrate more on control, he would tell him to deal with the cramp.

  12. Todd Austin says:
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    Coming down that fast and firing the engine that way is the only way to do it. Even throttled all the way down (70% max), the Merlin 1D thrust is several times more than the rocket weighs at that point. The goal is zero velocity at the landing surface. It can’t hover or come in slowly.

    • John Thomas says:
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      The grasshopper landings sure were slower.

      • Jeff2Space says:
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        They were slower because the Grasshopper landing legs were made of heavy steel, so no thrust to weight ratio greater than one (i.e. it could hover).

      • Hug Doug ✓ᵛᵉʳᶦᶠᶦᵉᵈ says:
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        They were coming down from a hover at a low altitude. Operational stages have been falling for some 50 miles before attempting to come to an abrupt halt right before the surface…

      • Todd Austin says:
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        Grasshopper carried a lot of fuel it didn’t really need in order to get the thrust-to-weight ratio more in balance. Grasshopper could hover. A returning F9 stage cannot.

  13. Steve Pemberton says:
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    The question though is whether the system can deal with it. It seems that the engineers believe that it can.

  14. enginear says:
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    So the grasshopper practice does not really help here since the landing modes are different?

    • John Thomas says:
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      Yeah. The descent rate is much less for the grasshopper tests. What they need to do is go up high, turn the engine off and then do a final descent like they’re trying with the first stage.

      • Yale S says:
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        I wonder if they chose a to do a hoverslam landing (AKA Suicide Burn) so as to minimize the effects of wind gusts and, in the case of sea landings, barge movement. Dunno. One thing that I don’t suspect they would do even with a lower speed approach is to cut the engine. Rolling the dice one too many times, maybe.

    • Dewey Vanderhoff says:
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      At one point SpaceX said they were going to take Grasshopper up to New Mexico , either White Sands AFB or the new civil spaceport there , and do some very high altitude higher speed landing tests that better mimic Falcon-9R’s final approach from an actual launch. Dunno what the status of that plan is, but it would give them a chance to refine the system using more real world conditions, and test hop more often. They can’t do that from their Texas test facility because they are surrounded by people , farms, and precious cows.

      • Hug Doug ✓ᵛᵉʳᶦᶠᶦᵉᵈ says:
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        That plan is still on, or at least, SpaceX is still continuing with construction of a test site there. It’s possible they will begin such testing using a recovered first stage.

      • hikingmike says:
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        The attempts from returning boosters are sort of “free” tests though. If they blow up, no big deal. If the next Grasshopper blows up, they have to make a new one. Over-simplifying but one way to look at it.

  15. Jeff Havens says:
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    Question — I understand the need to develop the automated systems for landing. But.. can there/is there the ability for manual operations/takeover when Falcon starts land landings? I get (based on Elon’s tweets mostly) that they can’t do live feed at the barge. Landing pad would be a different story. With is latest attempt, even having a kill switch on the engine 1-2 seconds sooner might have yielded better results (your expertise may trump that statement).

    • Todd Austin says:
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      It all happens to quickly, I would imagine that the computer would do a better job than a human.

      • Terry Stetler says:
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        A human can react to new sensory inputs and physically apply new control signals maybe sevetal times times a second, for visual stimuli the reaction time is about 150-200 msec – a neuromuscular speed limit, while a computer can do it over 100 times a second. No contest.

      • Lewis says:
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        Delta Clipper used human pilots, remotely. Fuzzy logic exists now, and was infantile then, or didn’t exist. Not sure. With fuzzy logic you don’t need a human pilot. Space X is definitely using fuzzy control.

  16. richard_schumacher says:
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    The video shows the barge heaving, which could tip the scales (as it were). I’d bet a dollar that their first attempt on land will succeed because the surface will remain where the software thinks it is.

    • Duncan Law-Green says:
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      It’s a video of a video — someone at SpaceX surreptitiously filming a screen with their phone. What you see as the barge heaving is likely just the guy’s hand moving.

  17. Granit says:
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    Too much thrust, moving deck and high center of gravity on the booster makes this approach inherently risky. Would be a nice demo, but will not be a reliable system without some significant change(s).

    • Hug Doug ✓ᵛᵉʳᶦᶠᶦᵉᵈ says:
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      What do you mean by too much thrust? The moving deck doesn’t matter much – the engine cuts off right at touchdown, things are happening so fast that the motion of the deck is negligible. The center of gravity is really low, actually – the tank is nearly empty at this point, and so most of the weight of the stage is in the engines. The CG should be below the topmost points of where the legs attach to the stage.

      • Granit says:
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        Engine is not able to throttle down below a t/w of 1.0. Timing has to be perfect, that’s why it is coming in too fast and not hovering before setting down. This problem is exacerbated by shape of the booster and a moving landing pad. All this combined makes it a very challenging manuever.

      • speragine says:
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        I thought the engine shut down slightly after touchdown, just the way the video looked to me, and I thought that may have contributed to the failure.

  18. John Adley says:
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    This is just as hopeless as simple mechanics can predict. The rocket should be spherical (or a spinning disc) for this method to work.

    • Jeff2Space says:
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      I have no idea what you’re talking about.

    • Yale S says:
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      I’ll copy your post to whatever thread covers the landing in june or the one in july.
      Simple mechanics are totally irrelevant in a managed system.
      No advanced military jet could fly if “simple mechanics” ruled its operation. They actually depend on the instability to increase performance.

      • John Adley says:
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        I would be glad to be proven wrong, but I don’t think this thing will work regardless if by chance or luck they land it once or twice in many tries, but that will prove nothing about reusability, no one will buy unreliability. If they throw many billions on the problem they probably will reach some not astronomically expensive system for NASA to buy, who knows? LOL

        Oh, please by all means keep records of anything people say on the internet and report back as many times as you please, that’s really a good way to wasting your life, if you have any.

        • Yale S says:
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          What does this have to do with NASA? NASA so far buys virgin machines. They have nothing to do with the stage recovery.

  19. John says:
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    I guess the fact that they are building landing pads must be what is throwing us off.

  20. NowWeTryItMyWay says:
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    That’s funny, since they’re planning to do so on their next attempt.

    http://www.defensenews.com/

    • John Thomas says:
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      Actually they’re hoping to do so.

      • Yale S says:
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        I think that extracted interview is a bit muddled.
        The next landing attempt is in two months on the barge for next cargo mission.
        It is the Jason flight out of Vandenberg in 3 months that is to land at the 4W landing pad.if all goes good.

        • Steve Pemberton says:
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          However I would think a decision would have to be made soon for the July launch. But I suspect that VAFB will not approve until they see a successful landing on a barge. The CRS-7 is scheduled to launch just one month before Jason-3 and that’s if CRS-7 launches on schedule. I think it might be more likely that the first landing attempt will be on SAOCOM 1A which is supposed to launch this year from Vandenberg although a launch date still hasn’t been set AFAICFOUOSE (as far as I can find out using online search engines)

          • Yale S says:
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            SAOCOM 1A is penciled in for November 2016 and SAOCOM 1B for October 2017.
            It will be tight, but I’m still betting on Jason 3 in July (if the cargo flight is a success on the barge)

        • DTARS says:
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          Well let me know so I can try to get that selfie with a rocket on a barge. I chased a falcon around all week and ended up with crispy falcon leg and my mug on a space blog.

          http://spaceflightnow.com/2

  21. Daniel Woodard says:
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    The entry trajectory is already designed to return to land; it was artificially tweaked to move the landing site offshore. The Falcon booster climbs steeply at first and separates somewhat closer to the launch site than the Atlas or Delta.

  22. DTARS says:
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    It won’t bounce if you do it high enough. You stop dropping high over the barg, hop up a little you make sure you are dead center over barge center, then you land. That would stop any last second moment issues Right??

  23. Jafafa Hots says:
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    If they’re intending to move to land landings (that sounds strange…) do you think maybe they’ll raffle off the barge? Or maybe sell it on eBay?

    Any other collectors out there? 🙂

    • Paul451 says:
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      The not-barges will be needed for some launch profiles, even after they achieve land landings. And will probably be needed to recover the core stage of the FH for all but the lightest payloads.

      This isn’t a one-off use. They won’t be raffling or selling “Just Read the Instructions”. They have, after all, built a second not-barge, “Of Course I Still Love You”.

  24. Yale S says:
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    The payload capacity of a Falcon 9 is sized specifically to allow the stage to be flown back to the landing pad.

    In July they are planning a land flyback at Vandenberg.
    We’ll see what happens.

  25. Lewis says:
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    It is interesting. I don’t think there’s a lot of faith in it on any side; the lease for lc13 is only five years.

    • Duncan Law-Green says:
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      If USAF Eastern Range didn’t have confidence in SpaceX’s stage recovery efforts, they wouldn’t approve attempts in the first place.

      • John Thomas says:
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        I’m not saying the AF doesn’t have confidence in SpaceX but what landing attempts have they approved? I wasn’t aware that the sea landings required AF approval.

        • Yale S says:
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          I read Duncan’s “approve” as meaning that they lease out and allow the modification to host landings, not a sign-off for any particular landing attempt. That most likely will come in July at vandenberg launch of Jason-3 for NASA/NOAA/CNES/EUMETSAT.

    • Yale S says:
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      45th Space Wing Public Affairs

      2/10/2015 – PATRICK AIR FORCE BASE, Fla. — Brig. Gen. Nina Armagno, commander, 45th Space Wing, recently signed a five-year leasing agreement with SpaceX that will allow for the creation of the first-ever “Landing Pad” at Launch Complex 13 at historic Cape Canaveral Air Force Station.

      SpaceX plans to repurpose the launch complex to successfully support their construction of a vertical-landing facility suitable for the return of reusable first-stage boosters of their Falcon 9 and Falcon Heavy launch vehicles that are currently launched from LC 40 at CCAFS.

      LC-13 was originally used for operational and test launches of the Atlas ICBM, and Atlas B, D, E and F missiles were also test launched from there.

      It was the most-used and longest-serving of the original four Atlas pads.

      Now it will be used in an amazing new way.

      “The way we see it, this is a classic combination of a highly successful launch past morphing into an equally promising future,” said Gen. Armagno.

      “It’s a whole new world, and the 45th Space Wing is committed to defining and building the Spaceport of the future,” she said.

      “For decades, we have been refining our procedures for getting successful launches skyward here on the Eastern Range. Now we’re looking at processes on how to bring first-stage rockets back to earth at the first landing pad at the Cape,” she said. “We live in exciting times here on the Space Coast.”

      – 30 –

  26. Littrow says:
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    Very exciting!

    Probably the most exciting NASA-associated video since the Minutes of Terror Mars Landing.

    Hope they succeed next time. For such a high CG they need longer landing feet to stabilize the stage once it settles down.

    • Ben Russell-Gough says:
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      The CG is actually a lot lower that some might think. Remember that about 85% of the vehicle’s volume is propellent tank, which is empty at the time of landing. Most of the mass is concentrated in the very bottom of the stage – the engines and the machinery for the landing struts. However, like any tall object, there is a ‘tipping angle’ and that was exceeded at this point.

    • Yale S says:
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      Elon Musk @elonmusk · Apr 18
      While the rocket does look rather tall & tippy, a stable landing is no problem with proper throttle response https://www.youtube.com/wat… …
      YouTube

  27. wwheaton says:
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    I think not. The stage is light, with little fuel after MECO. It takes relatively little to slow it down to the point where it can reenter safely. Then air resistance will slow it down to just ~300km/hr or so — so slow the rest is easy, except for the control issues. They do have to get its position, translation velocity (horizontally as well as vertically), rotational position, and rotation velocity, all correct within limits tho. Not trivial, but possible.

  28. Saturn1300 says:
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    The engine only throttles to 70%. Deep throttle may help. I did a search and came up with this:TGV’s Reusable Throttleable Rocket Engine 30,000 lbs (RT30) represents a
    significant advance in rocket propulsion capability for reusable flight
    vehicles. With a demonstrated wide throttling range of over 10:1,
    operation on military-standard jet fuel, and a design for low
    maintenance and long life, the RT30 is the ideal powerplant for
    operationally responsive space lift.
    If deep throttle would help, SpaceX may want to buy this engine technology. It might be able to be made bigger. It has been run.

  29. DTARS says:
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    When your goal is the golden goose getting a leg is pretty dam good 🙂

    The picture of me was taken the day before the barge came in. That is the crane that will transfer the falcon 9 to the truck. The ship in the background can only come in at low tide to get under the bridge, so the upright booster is not taller than that.

    Not the selfie I was hoping for, but every SpaceX flight means progress.

    The Affordable Reusable Space Age is almost here!

  30. Saturn1300 says:
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    The different sideways rates top and bottom is what caused the stage to be lost. It tilted and shut down the engine, the legs could not keep it from falling over. If the rates are the same it will not tilt and move over to the center of the target and shut the engine down. A good landing. Different possible rates top and bottom makes for a tricky balance. Proportional steering may work better than the flick steering they use in flight. Or using thrusters top and bottom may be better. The throttle valve was working fine since it was hovering. The throttle only controls rate of descent. As the fuel burns off it compensates, keeping the hover steady.

  31. Yale S says:
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    The Crew Dragon launch pad abort test has been penciled in for the morning of May 5.
    http://www.americaspace.com

    • Yale S says:
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      BTW, I think the Crew Dragon is ugly. The CST-100, Dreamchaser, and the Cargo Dragon are rather cute.
      Same goes for its interior. Hey, I’m not paid for my looks, either. (good thing, too!)

  32. NowWeTryItMyWay says:
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    Posting from JUST 9 MONTHS in the future to laugh at you