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SpaceX To Test Recovered First Stage, Then Put It On Display (floridatoday.com)

schwit1 writes: Rather than re-fly it, Elon Musk suggested that, after some testing, SpaceX will likely put its first recovered Falcon 9 first stage on display instead. '"[We will] do a static fire at the launch pad there, to confirm that all systems are good and that we are able to do a full thrust hold-down firing of the rocket," Musk said after the stage landed. The static fire will also test the modifications SpaceX has made to Pad 39A to support its rockets.

After that though, the stage will become a display piece. "I think we will keep this one on the ground for tests that prove it could fly again and then put it somewhere — just because it is quite unique," Musk said.' Since they already have a satellite company, SES, willing to buy that first stage, this only underlines how this last Falcon 9 launch changes everything. I don't think the change has sunk in with most people, yet. The last launch was not a one-time event. SpaceX intends to recover as many of its first stages as it can in all future launches. Their Falcon 9 first stage is no longer expendable. Thus, they can afford to put this first recovered stage on display because they expect all future first stages to fly again.

10 of 108 comments (clear)

  1. That's Ridiculous by localman · · Score: 5, Interesting

    You can't just take an amazing piece of expensive kit like that and essentially throw it away! Oh wait - that's what we've been doing with the first stage of every launch forever until just now. Carry on then.

    More seriously, congratulations, SpaceX, for taking such a big step forward for humankind.

    1. Re:That's Ridiculous by Rei · · Score: 4, Interesting

      There's a couple side effects of this capability that I haven't seen discussed in regards to abort as well.

      1) First stage partial failure abort to ground: If there's a non-catastrophic problem on the first stage that will prevent the payload from being injected into the proper orbit (for example, multiple engine failure), there's the potential to abort to ground. Now, this isn't exactly the same - they've still got a rather lot of weight on them (and correspondingly a lot of fuel inside); it'd help if the second stage were able to jettison its propellant (otherwise the nitrogen gas jets and grid fins have to work harder). But it might be possible to re-land the whole rocket, payload and all, so that they can fix it and then re-launch.

      2) Second stage hard abort to ground/sea: If there's a catastrophic problem on the first stage but successful separation of the second stage intact, they could try to "land" the second stage and provide partial potential for recovery of the payload. This is more difficult - the second stage has no grid fins, no nitrogen gas thrusters, no landing legs and only one engine. But burned out of propellant it's quite light, it probably has enough thrust, even with the payload attached - and if it just separated from the first stage, it certainly has enough propellant to get back to the pad and line itself up for a gentle, fully vertical descent. The lack of nitrogen gas thrusters would make stability much more difficult, they'd have to land just from gimbaling... but it's probably doable if crosswinds aren't too strong. And they have no landing legs, so they're going to damage the nozzle, and the thing may well fall over. But it's only 1/3rd the length of the first stage, so maybe not, it depends. At sea it'd fall over into water. In short, you could actually get your payload back not at a speed of "500 meters per second smack into the ground", but either "less than 1 meter per second" or "less than 1 meter per second, then a secondary lateral thud at several meters per second followed by the explosion of whatever residual propellant remains" Depending on the payload and how it's stowed, it could potentially be partially or completely reusable.

      --
      Shiny New Australia.
    2. Re:That's Ridiculous by Rei · · Score: 3, Informative

      Exactly. If they want the stats on their rocket to be comparable to SpaceX's, they need to reduce it to a quarter of its current weight (to match the wet/dry mass ratio of Falcon 9's first stage) and have it reverse about a thousand meters per second of lateral momentum and land without the ability to hover. Because these things are the consequences of SpaceX having to make something that functions as an actual first stage of a launch vehicle, rather than a joy ride for rich people.

      Good luck with that, BO.

      --
      Shiny New Australia.
  2. Re:Did they hire someone from NASA? by beelsebob · · Score: 3, Insightful

    That would indeed be the "smarter" thing to do in terms of pure engineering. In terms of company morale though, possibly not. It may be a much smarter management decision may well be to help everyone to realise how awesome an achievement they were just part of, and to keep company morale up, because it will increase productivity enough to offset the engineering benefit.

  3. Re:sentimental crap by U2xhc2hkb3QgU3Vja3M · · Score: 3, Funny

    Yeah! And let's dismantle those stupid pyramids in Egypt, too! Surely someone in that area could use those huge rectangle rocks!

  4. Re:Did they hire someone from NASA? by ColdWetDog · · Score: 5, Insightful

    Or, they've found a bunch of things they don't like and they are going to fix it before next flight. Like engineering.

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    Faster! Faster! Faster would be better!
  5. Great Moments in Private Enterprise Space History by PopeRatzo · · Score: 5, Funny

    2015: Space X recovers the first reusable rocket stage and doesn't reuse it.

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    You are welcome on my lawn.
  6. Re:Recovery != Reuseability by Beck_Neard · · Score: 4, Insightful

    You know nothing about rocketry.

    A rocket doesn't become damaged and non-recoverable just because it flew for five minutes through the air. The only reason people haven't been able to recover rockets up to now is because the actual act of taking a large moving object at 5000 km/h, decelerating it, maneuvering it through the atmosphere, and landing it gently is really really hard. That, and the thermal stresses on the engines mean that most rocket engines up to now have not been able to sustain multiple full-length firings without refurbishment.

    SpaceX has _already_ demonstrated that it has solved both of these problems. The Merlin rockets that SpaceX uses are actually fired around 10 times before even getting mounted on an actual launch vehicle! And no, they aren't 'refurbished' after test firing. The engines have been designed with full re-usability in mind - fill up the tank again and go. The launch vehicles themselves go through static firings before being launched through space. In static firings they get most of the vibration and thermal stresses that they would get if they were actually flying (most of these stresses come from the rocket engines). The point is that SpaceX is already 're-using' its stages. It's just that it has never re-used one that has not been strapped down to the ground. Given all of this, it would be MIGHTY strange if boosters that had flown could not be re-used.

    If you're betting on this being the case, don't. You'll probably lose the bet.

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    A fool and his hard drive are soon parted.
  7. Re:Recovery != Reuseability by Beck_Neard · · Score: 3, Insightful

    It's easy to pretend to know stuff. Everyone and their mother nowadays seems to be an expert on rocketry.

    It's harder to actually know stuff. The most important causes for failure on rockets are engine failures, software failures, and structural failures, in that order. Engine failures are typically caused by excessive vibration, thermal stress, combustion containment failures (hot gases touching the walls), turbopump failures, and a few other reasons, and these will often show up in static tests. In fact this is the whole point of static testing. As for software, it's the same whether you're re-using an airframe or not. Finally, as for structural failures, they are caused by vibration, thermal stress, and aerodynamic stress. Of these, a pretty good picture can be constructed from static testing, with only aerodynamic stresses left out. Granted, a single-engine test isn't very accurate for diagnosing problems; full-rocket static tests are better.

    While flying through the air in a normal mission profile puts a lot of stress on the airframe, it doesn't do any irreversible damage on the airframe, unless the rocket is very badly designed. Going outside the mission profile (facing the wind the wrong way) can and will do irreversible damage, but spacex are very careful to bring their rockets down gently. If you want to bet that a recovered falcon 9 first stage can't be used, the only way that argument will work is if you argue that the airframe somehow suffers irreversible damage during the recovery maneuver. Other than this, it would be extremely strange.

    --
    A fool and his hard drive are soon parted.
  8. Like the Spirit of Saint Louis by Steve1952 · · Score: 3, Insightful

    After Lindbergh flew the Atlantic Ocean in the Spirit of Saint Louis in 1927, he didn't then turn around and fly back. Instead he sent the Spirit of Saint Louis back to the US by sea. It now resides in the Smithsonian. This particular SpaceX Falcon 9 rocket is historically important, and quite possibly may also end up in the Smithsonian some day.