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SpaceX Launches Load to ISS, Successfully Tests Falcon 9 Over Water

mosb1000 (710161) writes "SpaceX is reporting that they've successfully landed the first stage of their CRS3 Falcon 9 rocket over the Atlantic Ocean today. This is potentially a huge milestone for low-cost space flight." In another win for the company, as the L.A. Times reports, SpaceX also has launched a re-supply mission to the ISS.

28 of 125 comments (clear)

  1. Not sure about the recovery test by cbhacking · · Score: 3, Interesting

    If you read the LATimes link, SpaceX says they believe the first stage recovery was probably not successful, on account of very rough conditions (25' waves - about 8m - where the rocket tried to come to a hover over the water's surface). They were sending ships out to see, but estimated the odds of success at only 40%.

    If anybody has an update on that attempt, please post it!

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    1. Re:Not sure about the recovery test by cbhacking · · Score: 3, Interesting

      Bah, sorry for the self-reply...

      "Data upload from tracking plane shows first stage landing in Atlantic was good! Flight computers continued transmitting for 8 seconds after reaching the water. Stopped when booster went horizontal. Several boats enroute through heavy seas..." is the latest we've heard. They're calling it a success, though, which is hopeful! I don't know if they were expecting to get more than 8 seconds or not, and whether "booster went horizontal" was expected or not (got hit by a wave, maybe?) - but they know a lot more about what constitutes success than I do.

      Pity about the rough conditions, though. Would have been *awesome* to see the first stage re-light and hover after a real launch. Maybe next time...

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    2. Re:Not sure about the recovery test by WindBourne · · Score: 4, Informative

      Data upload from tracking plane shows first stage landing in Atlantic was good! Flight computers continued transmitting for 8 seconds after reaching the water. Stopped when booster went horizontal. Several boats enroute through heavy seas...

      The issue is NOT whether they they recovered the stage, but whether it landed at slow controlled speeds. Apparently, SpaceX feels that it did 'land' on the water. As such, one or 2 more times with this, and they will be able to put it on land.

      Personally, I think that bringing it all the way back to the cape is a mistake. Instead, they should use one of the old oil rigs that are out there. Clean it up, land it on the rig, and then offload with a crane to a barge and take it back for launc.

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    3. Re:Not sure about the recovery test by MichaelSmith · · Score: 2

      The issue is NOT whether they they recovered the stage, but whether it landed at slow controlled speeds

      Also whether it landed at the planned location to within a metre or so, given that the plan is to land on a barge.

    4. Re:Not sure about the recovery test by beelsebob · · Score: 3, Informative

      No, the plan was to land in the sea, and to have helicopters near by. Only in the future do they plan to do very accurate landings.

    5. Re:Not sure about the recovery test by MozeeToby · · Score: 5, Interesting

      They soft landed, that's a success whether they are recovered or not. You didn't expect them to stand upright in the water like a buoy did you?

    6. Re:Not sure about the recovery test by Hadlock · · Score: 4, Informative

      The rocket (1st stage) when empty needs almost no fuel (about 4% of the total fuel at launch) to return to the launch site and land. The upgraded Falcon v1.1 has 10% more fuel at launch as well as increased cargo capacity (more efficient engines). Hitting a floating barge means you have to have good conditions at the launch site, as well as 400 miles out at sea as well. That dramatically limits your launch capability and exponentially increases your recovery costs.

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    7. Re:Not sure about the recovery test by Sivaraj · · Score: 4, Insightful

      The purpose of recovering it is to cut costs. Even if the stage becomes reusable, how much it is actually going to save is still an open question. In such case, landing it offshore, and transporting is not going to help with the costs.

      SpaceX is audacious, but I am sure they will take all precautions and won't attempt to land it in the pad, unless they are highly confident that it will work.

    8. Re:Not sure about the recovery test by benjfowler · · Score: 3, Interesting

      Even if there isn't much to reuse, there are tremendous advantages to recovering the engines, and having the engineers tear them down to the last nut and bolt. Merlin will end up becoming an incredibly reliable rocket engine -- even more than now.

    9. Re:Not sure about the recovery test by flyingfsck · · Score: 4, Funny

      Well, this is the commemorative weekend for an ancient Israeli dude who reportedly could walk on water, died and turned into a zombie. So, if that was possible, who knows, maybe Space-X can stand their rocket on water.

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    10. Re:Not sure about the recovery test by esperto · · Score: 5, Informative

      " You didn't expect them to stand upright in the water like a buoy did you?" Actually I would, when the booster from the shuttle land on water (here is a video https://www.youtube.com/watch?...) at first it goes horizontal but a few seconds later they go back straight up, because it is basically an empty cannister with some quite heavy engines on the bottom. IIRC before they start tugging the booster divers have to attach some hoses to pump water into the booster and make them go horizontal.

    11. Re:Not sure about the recovery test by cjameshuff · · Score: 4, Informative

      It got up there while carrying a lot more propellant and a whole second stage. The braking burn uses only 3 engines to limit the acceleration and ends with just enough propellant left to stop it when it reaches the ground. On top of this, it gets passive aerodynamic braking the whole way down.

      The mass ratio for the first stage burn, burdened with the second stage and braking propellant, is probably around 4, and a braking burn with equal delta-v would need the same mass ratio, except with no second stage and ending with the rocket empty. The overall first stage mass ratio is around 30, so all else being equal, a return would take around 3/29 = 10% of the propellant on the first stage. But all else is not equal, the returning rocket is mostly empty tanks descending through a thick atmosphere that provides plenty of braking, so the final burn only has to bring it to a halt from terminal velocity, and I omitted the second stage propellant. Overall, 4% sounds quite reasonable.

    12. Re:Not sure about the recovery test by WindBourne · · Score: 2

      I seriously doubt that spaceX has ANY intention of landing on barges. They move too much. Instead, an old oil rig would make far more sense.

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    13. Re:Not sure about the recovery test by cjameshuff · · Score: 2

      It doesn't need to brake to a complete stop and then retrace its outgoing path, it needs to bend it's largely-upward trajectory into one that comes back down over the landing site, and manage its velocity so it doesn't go too high and hit the atmosphere too fast on the way back down. As for the difference in separation speed, the flight profile for the reusable flights may very well take a more vertical trajectory during the first stage burn, the first stage taking on more of the gravity losses and going more for altitude rather than speed, and the ratio of propellant loading between the first and second stages may be different for reusable flights...they could oversize both at a minor cost in mass and tweak the ratio to suit the launch, the maximum loading being set by the first stage thrust rather than the total tank capacity.

    14. Re:Not sure about the recovery test by K.+S.+Kyosuke · · Score: 2

      Right, that is the only thing that would make sense - you simply can't use the traditional "flat" trajectory (because that wouldn't make the velocity vector "largely upward" - it's largely horizontal for expendable first stages) with such a small amount of fuel - you'd either need more fuel to cancel the horizontal momentum and to put it on a return ballistic trajectory (one that would have somewhere around 700-1000 m/s of terminal velocity in vacuum, though), or you could redesign the whole flight profile and use a combination of gravity and aerodynamics to save fuel when returning along a steeper trajectory, even if it means greater gravity losses for both the first and the second stage. I'm just uncertain about how they want to deal with the dynamic stresses when hitting the dense atmosphere at higher speeds. Well, I guess we'll simply have to accept that they wouldn't be doing this if they thought it wouldn't work.

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  2. And a Russian 'tug' was there by WindBourne · · Score: 5, Interesting

    Interesting that a russian naval ship (called a tug, but how many miles off florida coast ? ) was there at the landing site to watch this.
    I think that everybody who continues to knock SpaceX, is realizing that they are all in serious trouble.

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  3. Test and launch are the same, it is GREAT! by wisebabo · · Score: 3, Informative

    The landing of the first stage in the Atlantic (a process that required decelerating it and bringing it to a hover just above the surface of the ocean before letting it fall in), is part of the resupply mission to the ISS. That is, once the first stage boosted its cargo towards the ISS, it then performed this test.

    Too bad that they didn't try to return the first stage to land and then try to land it there but I understand their desire to do things one step at a time (it's safer this way also). I'm curious to know if this first stage had landing gear attached (maybe not because of the additional weight, drag). Also, in the future when they DO try to land it on land, where will they be aiming? If the flight profile of the first stage is mostly vertical then, without much fuel I guess they could return to Florida, otherwise would they be going for a Caribbean island? The Azores or Canary Islands? Africa? I'm sure they've got this figured out, I'm just curious.

    Anyway, if they manage to recover the first stage by soft landing it without dunking it in salt water, it could REALLY drop the costs of space flight, even if they don't manage to reuse the 2nd stage (which they plan to do also). I remember reading that of the $20 million cost of a launch only about $500,000 was due to fuel, so this is a complete game changer. Even if the stage can only be reused a few times it'll make access to low earth orbit (the expensive part of space travel) much cheaper!

    I only hope and pray that it works reliably and that the weight penalty is not too great! I thought they would have to use a lot more fuel to slow down and turn around but I guess they're using air resistance for the braking and the (now almost empty) booster is very light. Pretty unbelievable when you see a 10 story tall rocket turn around and land on a pillar of fire.

    1. Re:Test and launch are the same, it is GREAT! by clj · · Score: 2

      > I'm curious to know if this first stage had landing gear attached

      Yes, and they were hoping that that would contribute to ameliorating the roll problem they had on the first attempt to slow down the first stage on its way to landing (actually, watering). So, the bad sea conditions and (most likely) not recovering the first stage are unfortunate but it seems like they are making progress, and doing so without interfering with performing a successful mission for a paying customer.

    2. Re:Test and launch are the same, it is GREAT! by wagnerrp · · Score: 5, Informative

      I remember reading that of the $20 million cost of a launch only about $500,000 was due to fuel, so this is a complete game changer.

      Right idea, but wrong numbers. A Falcon 9 launch, not including the cost of the payload itself, is nearly $60M, while the fuel for it is only a quarter million.

    3. Re:Test and launch are the same, it is GREAT! by gman003 · · Score: 4, Interesting

      I'm curious to know if this first stage had landing gear attached (maybe not because of the additional weight, drag). Also, in the future when they DO try to land it on land, where will they be aiming? If the flight profile of the first stage is mostly vertical then, without much fuel I guess they could return to Florida, otherwise would they be going for a Caribbean island? The Azores or Canary Islands? Africa? I'm sure they've got this figured out, I'm just curious.

      This test did have the landing gear attached and deployed during landing, as the aerodynamics of it are potentially problematic (one of their tests failed when it entered a spin before landing).

      The first stage flight path doesn't seem to be mostly vertical - I'm having a hard time finding solid info, but based on images of the first-stage separation, I'd estimate it to be no more than a quarter of the way across the Atlantic. I do know that their plan is to return the rocket to the launchpad for landing, which wouldn't make much sense if it was much further away by stage 1 separation.

      Their flight path does seem a bit weird, though - of the Space Shuttle abort modes, Return to Launch Site was the riskiest and most difficult, compared to Transoceanic Abort Landing (landing in a European or African site) or Abort to Once Around (doing a full orbit then landing as normal). Either the Falcon is accelerating far faster once they break the atmosphere, or the Space Shuttle accelerated horizontally a lot earlier than it may have needed to.

    4. Re:Test and launch are the same, it is GREAT! by subreality · · Score: 4, Informative

      RTLS, TAL and AOA all relied on the main engines. If all three SSMEs failed they would have ditched it in the Atlantic. The scenarios aren't really comparable - they had a lot more fuel to work with but also a much heavier vehicle to return.

      RTLS is easier for the Falon 9. After separation the stage 1 assembly is quite light: it has shed the payload, second stage, and most importantly, most of its own fuel; the remainder is about 5% of the original mass. It can therefore make a pretty quick burn to reverse its course.

      They have some real numbers over here: http://forum.nasaspaceflight.c... .

    5. Re:Test and launch are the same, it is GREAT! by DougF · · Score: 2

      About 400 years ago: "And what will you do when you get to the new lands? It's mostly empty, just a few natives prowling about, and a lot of trees. What's the obsession?" Answer: "To get the fuck out of here..."

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  4. Re:What a shame. by CrimsonAvenger · · Score: 2

    China in particular understands that progress comes not from the Invisible Hand, but from directing your resources to a primary goal of human development.

    Which, presumably, is why China has done in 40 years what it took the US eight years...

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  5. And again in English please? by clickclickdrone · · Score: 3

    SpaceX Lands Launches Load to ISS

    WTF?

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  6. Re:What a shame. by Anonymous Coward · · Score: 3, Insightful

    Perhaps, but NASA made their own bed to lie in half a century ago when they decided their launch systems should be made of the most pork possible. No need to scoff at private enterprise being more efficient and agile than government.

    Basically, this is a story about SpaceX continued success and the fact they are pushing technological boundaries. However, you managed to squint at this and see nothing but squalor, failure, and abrogation of duty, plus a hint of civilization collapse.

    You seem to be a person who delights in finding the cloud behind every silver lining. This is odd for me to say, because I'm a goddamn engineer and no one has ever accused me of not being cynical.

  7. Cost breakdown by Immerman · · Score: 2

    So, is NASA currently paying a nearly 3x premium to SpaceX just to get their technology off the ground or what? Not that I object to such long-term thinking, quite the opposite in fact, but I could swear the SpaceX contract was marketed as a cost-saving maneuver.

    It says here that it currently costs $10,000 to get a pound of payload into orbit, but from TFA SpaceX has a $1.6 billion contract for 12 launches, and if the current ~5000 pound payload is typical that works out to ~$27,000 per pound. Granted, assuming SpaceX perfects the reusable F9 that stands to potentially reduce launch costs 5 to 20-fold, easily making it one of the cheapest options available, even assuming that the current contract strictly covers launch costs and profit and without any R&D budget. But it's hardly a cost-saving maneuver in the short term.

    Also, gotta love the phrasing in the summary "In another win for the company, as the L.A. Times reports, SpaceX also has launched a re-supply mission to the ISS." As though completing the mission that's actually paying the bills was just an added bonus.

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  8. Re:What a shame. by CrimsonAvenger · · Score: 2

    This has way more to do with the political motivation to spend the money required than technical know how.

    And the Chinese inherited the technical knowhow, since they went after the US. So, given the technical know-how, the Chinese still took 40 years, after watching us do it in eight.

    Yeah, there was a lot of "who cares?" from China that saw them ignore space for a long time. But even after they started taking it semi-seriously, there was still a couple decades before they managed that lunar lander (made with 21st century tech) that the US did in eight years (using 1960's tech).

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  9. Re:What a shame. by catprog · · Score: 2

    Was it NASA or the senators in charge of funding who decided that?

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