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SpaceX Details Its Plans For Landing Three Falcon Heavy Boosters At Once (arstechnica.com) 101

An anonymous reader quotes a report from Ars Technica: As part of the process to gain federal approval for the simultaneous landing of its Falcon Heavy rocket boosters in Florida, SpaceX has prepared an environmental assessment of the construction of two additional landing pads alongside its existing site. The report considers noise and other effects from landing up to three first stages at the same time. After undergoing a preliminary review by the U.S. Air Force, the document has been released for public comment. As part of the document, SpaceX also says it would like to build a Dragon capsule processing facility on the landing zone to support refurbishment of the Dragon 2 spacecraft, designed to carry crew into orbit. The 130-foot-long facility would provide a "temporary" facility for vehicle propellant load and propulsion system servicing. When it originally designed its Landing Zone 1 facility at Cape Canaveral Air Force Station, for the single Falcon 9 first stage booster, the company envisioned the need for one main pad approximately 200 feet across, and four smaller contingency pads, each approximately 150 feet in diameter. The chosen site had enough acreage to accommodate all five pads. Improvements in the rocket's landing navigation guidance system obviated the need for the contingency pads with the Falcon 9, however. So now the company wants to use the additional space to construct two concrete landing pads, each with an approximate diameter of 282 feet surrounded by an approximate 50-foot-wide hard-packed soil "apron." This would give SpaceX three landing pads and the ability to bring back all three Falcon Heavy boosters to land while also retaining the option to land one or two on drone ships in the Atlantic Ocean. In addition to the potential for a dozen Falcon 9 launches and landings each year, the document says SpaceX may eventually make six Falcon Heavy launches a year, potentially returning an additional 18 boosters to the Florida-based site. The new pads and crane sites would be configured to allow parallel processing of landed boosters. With U.S. Air Force Approval, construction could begin as early as this spring.
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SpaceX Details Its Plans For Landing Three Falcon Heavy Boosters At Once

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  • are under NCAA review
  • by Michael Woodhams ( 112247 ) on Wednesday January 11, 2017 @11:52PM (#53651933) Journal

    "This would give SpaceX three landing pads and the ability to bring back all three Falcon Heavy boosters to land while also retaining the option to land one or two on drone ships in the Atlantic Ocean."

    I can imagine scenarios where you'd want to land zero, one or three boosters on drone ships. I can't imagine any scenario where it makes sense to land two boosters on drone ships. One way would be to have the center booster and one side booster landing at sea - but if one side booster can return to landing site, so can the other (and landing on land is both cheaper and safer if you can do it.) The other way is to land both side boosters at sea but return the center booster to land - but the center booster is always going to be much harder to return to land, as it burns longer and so is higher velocity and further down range when it has finished boosting.

    • by werepants ( 1912634 ) on Wednesday January 11, 2017 @11:58PM (#53651949)

      Landing two boosters on drone ships could be desirable for a payload that's close to the performance limit of the Falcon Heavy, such that the center core uses all of its fuel and is expended. In such a mission, it's very possible that the side cores wouldn't have the fuel margin to boost all the way back to the launch site. So that launch profile would be close to the maximum performance of Falcon Heavy. Maximum would be expending all three cores and retaining no fuel to recover any of them. There could also be a hypothetical scenario where the center core completes one or more orbits and then returns to the landing site, while the two boosters land downrange on the drone ships.

      • One more scenario is if the third booster were to land across the Atlantic ocean somewhere dropping the boosters short.
        • Does NASA still have the facility in Morocco which was an abort landing location for the shuttle fleet? [Checks] They used different sites at different times, one in France, two in Spain, one in England. I'm probably mis-remembering one of the Spanish sites.
    • With thrust vectoring it's in theory possible to do the staging where you shed 1 booster at a time, with fuel crossfeed to the other 2. The Delta IV can be launched like this, with just one SRB on one side. Whether or not this will be possible with the Falcon Heavy depends on how they build it, and realistically which version of the rocket it is. (since SpaceX keeps making changes)

      • Crossfeed is not planned for F9H in the near term. They may get to it eventually.
        • Crossfeed is not planned for F9H in the near term. They may get to it eventually.

          What would it take to get from here to there?

          • Falcon 9 (the non-heavy one) is about to go to its 5th major revision, and there have been major increments to its capability with each one. So, it will probably just take time for a version of F9H to have crossfeed and some additional delta-V. It was possible to get F9H going without the added complexity, so they did.

          • The main reason why crossfeed isn't being worked on is that the extra capacity it would deliver isn't needed by any customers. The heavy is already a beast of a launcher without it. But, if someone came up with a mission that required the extra capacity and was willing to pay for its development, then they would restart work on crossfeed.
            • If they advertise a full-thrust mission capability, someone will make something to use it.
              • "Build it ; they will come?" Motto of the approaching sexbot industry which will lead to huge advances in practical robotics in the same way that pr0n drove the commodity-level advance of computing.
    • by khallow ( 566160 )

      (and landing on land is both cheaper and safer if you can do it.)

      It might be cheaper, but it's not safer. There's more stuff to hit on land. I think you might be a bit concerned if a Falcon booster tried to land in your backyard.

      • Actually, all of the ground landings take place right next to the ocean. The rocket doesn't vector over the land until it's close to the ground, and the landing pad has lots of buffer zone around it.

        Consider the financial impact, too. A successful landing is saving 35 Million dollars.

        • by khallow ( 566160 )
          Point is with a sea landing, you can make it physically impossible for the booster to land in someone's backyard.
          • You've never heard of Ariel, I take it.

          • Point is with a sea landing, you can make it physically impossible for the booster to land in someone's backyard.

            This is Florida we're talking about.
            Or maybe Texas.

            Come on.

          • It all comes down to priorities - landing on land is dramatically safer and cheaper *for the rocket*.

            As for not landing in someone's backyard, that's an unavoidable risk even while they're going up. And while coming down, Falcon 9 landings are already vectored so that they will land at sea if anything goes wrong, it's only during the last minutes of final approach that they change that vector to hit the launchpad instead.

            • by khallow ( 566160 )

              It all comes down to priorities - landing on land is dramatically safer and cheaper *for the rocket*.

              As you imply in your next paragraph, safer != riskier.

              As for not landing in someone's backyard, that's an unavoidable risk even while they're going up. And while coming down, Falcon 9 landings are already vectored so that they will land at sea if anything goes wrong, it's only during the last minutes of final approach that they change that vector to hit the launchpad instead.

              So I see two things here. First, the rocket has to go up so that's the same unavoidable risk no matter where you land the booster. And second, you can vector the rocket so it does land in someone's backyard. Admittedly, they would self-destruct the rocket, if it veered from the desired trajectory, so that's not as much a risk as I made it out to be.

          • Point is with a sea landing, you can make it physically impossible for the booster to land in someone's backyard.

            That's not why they are done. Sea landings are done so they can land at all, since geo transfer orbital launches require so much energy/fuel that returning boosters to launch-site is physically impossible. If they could they would never ever do sea landings at all.

            Landing on land is a 10 times simpler and a lot safer (for the rocket) ;-)

        • Actually, all of the ground landings take place right next to the ocean.

          It's not that hard to conceive of a rocket booster coming back to Earth going off course by a fair distance and "landing" where it shouldn't. Definitely less chance of harm to property if this happens over the ocean than over land. It's not a worry that keeps me up at night or anything but it's certainly among the possible outcomes.

          • by Terwin ( 412356 )

            Actually, all of the ground landings take place right next to the ocean.

            It's not that hard to conceive of a rocket booster coming back to Earth going off course by a fair distance and "landing" where it shouldn't. Definitely less chance of harm to property if this happens over the ocean than over land. It's not a worry that keeps me up at night or anything but it's certainly among the possible outcomes.

            Have you ever been to Cape Canaveral?
            The little pointy bit is an Airforce base, and basically the rest of it is owned by NASA, mostly devoted to a secure zone/wilderness preserve.

            Then you have a nice long causeway with a lots of water as a further buffer before you get to anything like privately owned land.

            I am pretty sure that SpaceX has some means to destroy the returning booster before it gets close to the ground the 10+ miles off course it would need to be before getting close to private property.

            • Have you ever been to Cape Canaveral?

              Several times. Been on a tour to the VAB as well.

              Then you have a nice long causeway with a lots of water as a further buffer before you get to anything like privately owned land.

              According to Zillow there are over 100 houses for sale on Cape Canaveral just south of the Air Force Base as I type this. There are thousands of homes just a few miles to the west of the launch sites. A very reasonable safety buffer but not so far away that one could reasonably claim zero chance of something heading the wrong way.

              I am pretty sure that SpaceX has some means to destroy the returning booster before it gets close to the ground the 10+ miles off course it would need to be before getting close to private property.

              As am I. However the mere fact that such a thing would be necessary indicates that it is possible (however unlikely) for the ro

          • Very, very few people who live within fifteen miles of Cape Canaveral lived there before they built a space complex. And many, many more of them have been killed driving to the shopping mall since they built a space complex.

            Nobody would live there if absolute safety was the criteria for Vespucci or the Seminole - it's an unreasonable standard for real life.

          • by Megane ( 129182 )
            That's why they have a self-destruct mechanism. If it goes off-course, they push the button and it goes boom in the sky, not on the ground. Once it goes boom and becomes little bits, there is no more horizontal acceleration, and the debris falls below where the boom happened, which will likely still be over the water.
      • It's safer for the rocket, a platform that isn't pitching and rolling leads to a higher probability of a successful landing.

        Besides, Cape Canaveral isn't anyone's back yard. If things threaten to go haywire, they'll use the self-destruct and rain debris on unpopulated areas long before it can get to inhabited land.

        • Cape Canaveral isn't anyone's back yard.

          Cape Canaveral is just a few miles from quite a few people's literal back yards. It's not terrible hard to imagine a returning rocket booster (or parts of one) going off course by a few miles. Not likely I'll admit but not entirely impossible either.

          • Which is why it comes down to risk assessment. Nothing will ever be safe - if rockets landing nearby raise your chance of dying this year by 0.1% (of your previous chance of dying this year) then the risk isn't worth concerning yourself over. Eating the occasional greasy cheesburger is more dangerous.

    • A particularly high thrust launch which results in the boosters being downrange enough to require drone ship landings, while the core is sacrificed even further down range...

      Those kind of launches are planned for with the Falcon 9 already, with the intention of using older, used cores on those missions.

      Why not use three drone ships? Because you would need decent weather in all three landing locations - two of which are close together and thus are likely to share conditions, but the one further downrange wo

    • How about 1 central F9 with 3 external F9's which land back at the cape whilst the central F9 is either discarded or lands on a drone ship located conveniently for where it detached.
  • If you want to view the launch live, instructions are here [perens.com].
  • This definitely seems like a "Hey hold my beer, and watch this!" type of scenario with predictable results... Though you never know with these guys, landing a rocket on end, on a floating platform in the ocean also seemed a bit nuts yet they did it anyway.

    • Well, the plan has always been to eventually bundle at least three, and up to nine or more, rockets together to achieve launch capabilities far in excess of a single rocket without dramatically increasing the cost by building huge specialty rockets. And if they go up together, they'll need to come down together (well, anything that doesn't make it all the way to orbit)

      There are some serious challenges with the proposal, but mostly with the "going up" part of the equation. If you can land one autonomous ro

  • For a forward-looking company, they seem to think that the last 40 years of space travel never even happened.

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