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All of the Falcon Heavy launches up to now are either expending the Center core and landing the side boosters on land, or expending all of them (some examples: Falcon Heavy test flight, both boosters recovered but center core crashed into the ocean. Viasat 3 mission, all cores expended. SpaceX Falcon Heavy test flight video, and viasat 3 launch video)

Until now, SpaceX has never tried recovering all 3 Cores by seam wouldn't that cater to the needs of satellite that do not need to expend all of the cores to get to the desired orbit and also save a lot of money in having the option to reuse the cores.

Will they ever try it? Or will they not since re-entry speeds and heat would grossly overweigh the benefits? Re-entry heating as observed on Echostar 105/SES-11 mission, (Credit: SpaceX Echostar 105/SES-11 launch) where the grid fins heated up to white hot during re-entry. Could re-entry heating on the Center Core when landing be why they will never attempt it? Can someone give a answer?

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  • $\begingroup$ Not really. I want a definite answer that I can mark $\endgroup$ Apr 14 at 14:13
  • $\begingroup$ Since the answers to that question explain why the center core is not recovered, please let us know what additional info you need. $\endgroup$ Apr 14 at 14:21
  • $\begingroup$ After reviewing the earlier question, I believe that this question is not a repeat. It's asking about a specific configuration that was not covered in the earlier answers. $\endgroup$
    – phil1008
    Apr 14 at 15:57
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    $\begingroup$ @phil1008 can you be specific about the specifics? $\endgroup$ Apr 14 at 16:58
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    $\begingroup$ Well the question is about landing all three boosters at sea. To do this SpaceX would perhaps have to either land both side-boosters on a single drone ship, or field three drone ships. Plus there would probably need to be a mission that requires launching a heavy payload to a LEO orbit. So maybe larger fairings would be needed too. I think this is all new territory not covered by the previous answers. I also agreed with what this article had to say. $\endgroup$
    – phil1008
    Apr 14 at 21:20

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Feasibility of landing all 3 Cores of the Falcon Heavy on Droneships

That would require three ASDS in the landing zone which SpaceX does not have. Therefore, it is not feasible.

All of the Falcon Heavy launches up to now are either expending the Center core and landing the side boosters on land, or expending all of them

This is not correct, or at the very least, a very misleading way to state this. There are three Falcon Heavy flights where all three boosters were attempted to be recovered, on two, the landing of the center core failed in the last second, on the third, the center core successfully landed:

On the very first Falcon Heavy flight, the Falcon Heavy test flight, SpaceX successfully landed both side boosters at LZ-1 and LZ-2 and attempted to land the center core on the ASDS Of Course I Still Love You. Unfortunately, the center core ran out of TEA-TEB igniter fluid, so only one of the three landing engines re-ignited and the center core missed the ASDS by 100m, damaging two of the ASDS' station-keeping thrusters.

https://www.youtube.com/live/wbSwFU6tY1c?t=1833

On the second Falcon Heavy flight, the Arabsat-6A mission, SpaceX successfully landed both side boosters at LZ-1 and LZ-2 and successfully landed the center core on the ASDS Of Course I Still Love You. Unfortunately, the center core then fell overboard during the voyage back as the ASDS encountered rough seas.

https://www.youtube.com/live/TXMGu2d8c8g?t=1774

On the third Falcon Heavy flight, the STP-2 mission, SpaceX successfully landed both side boosters at LZ-1 and LZ-2 and attempted to land the center on the ASDS Of Course I Still Love You. Unfortunately, the center core, due to high re-entry heating, the heat shield of the E9 (center) engine was breached and the thrust vector control system was damaged. This means that, after the outer two engines shut down in the 1-3-1 landing burn sequence, there was no way to control the center core any more, since the grid fins are also ineffective at low speeds. As a result, the center core crashed right next to the ASDS.

https://www.youtube.com/live/WxH4CAlhtiQ?t=2165

Until now, SpaceX has never tried recovering all 3 Cores by seam wouldn't that cater to the needs of satellite that do not need to expend all of the cores to get to the desired orbit and also save a lot of money in having the option to reuse the cores.

Are you sure that it would save a lot of money?

First off: SpaceX is building rockets cheaper than anybody else (possibly with the exception of Astra, but their rockets are much simpler and less powerful and serve a different market). So, it is not clear that a center core is even expensive in the first place.

Secondly, you also have to consider all the other associated costs. In order to perform a triple-droneship landing, SpaceX would have to ship the ASDS Of Course I Still Love You from the Port of Los Angeles to Port Canaveral. OCISLY is too wide for the Panama Canal, so its landing deck extensions will need to be cut off and re-installed, which is what happened when ASDS Just Read The Instructions made the same journey. This can't be cheap either. Alternatively, SpaceX could choose to put the ASDS onto another ship, which is what they did when OCISLY went from Port Canaveral to the Port of Los Angeles. This is also expensive. Oh, and of course, SpaceX will have to ship it back after the landing.

And lastly, you need to consider the opportunity cost: the fastest SpaceX has managed to ship an ASDS from coast-to-coast so far has been 26 days. Let's say they don't go Port Canaveral but go directly to the landing zone, and let's further assume this saves 3 days, then it still takes 23 days to get from the Port of LA to the landing zone. The fastest SpaceX has been able to bring an ASDS back from the landing zone to Port Canaveral was 50 hours, and that required a much bigger and more powerful, and thus more expensive tug boat. But, a Falcon Heavy center core on a triple-droneship landing will be more than twice as far out at sea, so it will take at least twice as long. The fastest turnaround time for an ASDS in the port has been ~10 hours.

So, in total, this means that JRTI will not be able to support a recovery for a launch from SLC-4E on Vandenberg Space Force Base for at least about 55 days! If any customer missions launch during this time, SpaceX will have no choice but to expend the booster. For Starlink missions, SpaceX will have to launch significantly fewer Starlink satellites in order to enable an RTLS landing on LZ-4.

Will they ever try it?

This question is not answerable without time traveling to the future, unfortunately.

However, my best guess is that they will not. It simply makes no sense.

The #1 factor limiting SpaceX's launch cadence right now is turnaround time for the droneships. Your proposal would do nothing to fix that, on the contrary, it would take a droneship out of service for more than 1.5 months. Even if a third ASDS were to magically appear in Port Canaveral, I am still not convinced it would make sense to tie it up for 9 days for one Falcon Heavy launch when you could use it for two regular Falcon 9 launches in the same time.

Factor #2 is building second stages. Recovering a Falcon Heavy center core has no impact on that.

So, the only thing SpaceX saves is building a new Falcon Heavy center core. But Falcon Heavy launches so infrequently that this has no impact on the launch cadence. And a Falcon Heavy center cannot be used for anything else, so it would just sit around occupying storage space – center cores are physically built stronger since they have to carry all the structural loads of the side boosters. It is not possible to convert a single-stick or side booster Falcon 9 to a center core. It is theoretically possible to convert a center core to a single-stick, but it would be a lot heavier and thus not make economic sense. Given that Falcon Heavy only launches every couple of months, it is easy to squeeze in a center core here and there on the production line.

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    $\begingroup$ Looks like one-boxing of the YouTube videos is not working for live videos. $\endgroup$ Apr 14 at 22:53
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    $\begingroup$ "That would require three ASDS in the landing zone which SpaceX does not have." I mean, the solution to this is build/buy more droneships. Honestly something they should do anyway, based on their increasing launch cadence $\endgroup$ Apr 15 at 6:56
  • $\begingroup$ @fyrepenguin I think the corporate orthodoxy at SpaceX is that Falcon 9 is nigh to be replaced by Starship, so why invest capital in a dying program. It's already the highest-cadence rocket in the world. $\endgroup$
    – Erin Anne
    Apr 15 at 18:48

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