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From the latest news about the prior flight of Starship

For this demo, SpaceX won’t attempt any landings of the rocket or the spacecraft. Everything will fall into the sea.

Since SpaceX has never landed a Starship uccessfully - the only marketed success resulted in such damage to the craft that a subsequent fire successfully - why not keep trying to land the Starship and booster? When the craft is built to be reusable anyway, does it require substantially more hardware to attempt a landing then to intentionally drop it into the sea?

The current launch cost must be far in excess of 10 Million if that's what Musk wants to be in 3 years, considering Musk's pattern of absurdly unachievable goals.

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  • $\begingroup$ At the very least, it requires a landing pad capable of supporting the landing of a hundred tons of lightly fueled spacecraft, and all the necessary emergency hardware and personnel in the situation where it doesn't land successfully on the pad. $\endgroup$
    – notovny
    Jul 5, 2023 at 17:16
  • $\begingroup$ Sure, but isn't the pad built and how much are we talking about for "necessary emergency hardware and personnel in the situation"? $\endgroup$ Jul 5, 2023 at 17:20

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The landing mechanism for both is the Mechazilla tower arms.

They are not ready to test that yet. They need some more flight into to be certain they can fly the booster (and ship) with the accuracy they need to actually get between the arms, and hover long enough for the arms to latch on and catch the booster/ship.

Thus the booster is intended to do a mostly boost back burn, and do a fake landing in the Gulf of Mexico, off shore from Boca Chica, and pretend it is landing next to Mechazilla, and practice the technique first.

The first test flight did not get this far so they need to repeat it.

The ship is mostly testing the heat shield system and the rest of reentry (Flaps, sufficient aerodynamic control, etc) and if it makes it as far as the ocean will likely fly the proper profile to pretend to land as well.

These are test flights, and they intend to test a lot in the first (or second) flight, but landing is not yet on their list, since so many other things can go wrong first before they even get a chance at landing.

Additionally, when you see how much damage launch did to their only functional tower, they need to be careful with landing not to damage it in yet another different fashion.

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    $\begingroup$ "The ship […] will likely fly the proper profile to pretend to land as well." – The FAA's "Re-evaluation of the Programmatic Environmental Assessment" which was published together with the launch license for the first test flight makes it clear that the ship is intended to belly-flop right into the ocean, ensuring maximum probability of it fully disintegrating and sinking, requiring no cleanup and posing no marine hazards. The FAA and SpaceX expecs the methane downcomer to be ripped off due to the lateral loads and thus methane and oxygen mixing in the oxygen tank and exploding. $\endgroup$ Jul 9, 2023 at 6:51
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    $\begingroup$ Quote: "Starship would impact the Pacific Ocean intact, horizontally, and at terminal velocity […], and the impact would disperse settled remaining propellants and drive structural failure of the vehicle. The structural failure would immediately lead to failure of the transfer tube, which would allow the remaining LOX and methane to mix, resulting in an explosive event." This is for the first flight. For the second and third flight, it is planned to expend the ship, i.e. have it break up in the atmosphere. (Although, of course, SpaceX can amend its application and the FAA its license at will.) $\endgroup$ Jul 9, 2023 at 6:52
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Reusability is certainly an integral part of the long term goals of Starship. In fact it is enough of a priority that tests related to landing have been included in each Starship test flight. However the idea that the test program is driven by the need to prove landing capability does not match what appears to be the strategy of the Starship test program. And in fact it was not the strategy for the early Falcon 9 program, which had the successful and safe launching of payloads to orbit as the top priority, with development of booster recovery capability as a secondary priority. Even though from the beginning booster recovery was an important long term requirement of Falcon 9, as it is with Starship.

Like Falcon 9, Starship can conduct successful missions without recovering the Starship, or the booster, or even neither. You are correct though that for long term cost benefit, and I would add schedule benefit, successfully landing and recovering a high percentage of boosters and Starships is a requirement for maximum program success. Crewed launching and landing is a separate topic, and in my opinion is not a given in the Starship program, which I suspect can be an economically successful program even without launching crew.

Looking at the Falcon 9 test program, there were the Grasshopper and FR9 Dev1 single stage launch and landing test flights which in some ways can be compared to the Starship high altitude tests. Although the Starship tests were much more ambitious, each of them reaching at least 10 kilometers, compared to the highest known FR9 Dev1 test flight of 1 kilometer.

I realize that you do not consider the SN15 flight as having successfully landed, but in fact it did successfully demonstrate landing capability. A small fire occurred after landing, and due to the lack of fire suppression capability at the landing site the fire burned itself out after about 20 minutes. Presumably SpaceX determined the cause of the fire and has made the needed corrections, and apparently felt that the landing was successful since they decided that there was no need to perform another landing test.

I think it’s worth quickly going through the Falcon 9 landing attempts leading up to the first successful landing on the 20th Falcon 9 flight. First as a reminder of the early struggles that have in some ways been forgotten. But also to highlight that as a launch vehicle Falcon 9 had tremendous success in spite of repeated failures attempting to recover the booster. The pattern that we see with Falcon 9 may possibly portend how the Starship landing tests will go. Although with their prior experience SpaceX may possibly have success landing the booster and recovering Starship from orbit much sooner than the 20 flights that it took Falcon 9 before its first successful landing. It should also be noted the number of Falcon 9 flights that did not attempt to recover the booster. As SpaceX made ongoing modifications to the boosters to enable successful recovery, they did not allow it to hold up the pace of satellite and Dragon capsule launches.

The first two Falcon 9 test flights in 2010 were considered a success, the first flight put a test payload into the target orbit, and the second flight successfully launched the Cargo Dragon COTS Demo 1 flight. Even though in both test flights the attempted booster recovery by parachute failed when the boosters burned up during reentry.

The next three Falcon 9 flights successfully delivered their payloads to orbit, however no attempt to recover the booster was made on these flights.

On the sixth Falcon 9 flight, after successfully launching a satellite, the booster attempted a water landing, identical to what the first Starship test flights are doing. The booster lost control shortly before reaching the water.

The next two Falcon 9 flights successfully delivered their payloads to orbit, however no attempt to recover the booster was made on these flights.

The next two Falcon 9 flights successfully delivered their payloads to orbit, and both boosters made successful water landings.

The next two Falcon 9 flights successfully delivered their payloads to orbit, however no attempt to recover the booster was made on these flights.

The next Falcon 9 flight successfully delivered it’s payload to orbit, however the booster failed an attempt at a water landing.

The next Falcon 9 flight successfully delivered it’s payload to orbit, however the booster failed an attempt to land on a drone ship.

The next Falcon 9 flight successfully delivered its payload to orbit, and the booster made a successful water landing.

The next Falcon 9 flight successfully delivered its payload to orbit, however no attempt to recover the booster was made on this flight.

The next Falcon 9 flight successfully delivered it’s payload to orbit, however the booster failed an attempt to land on a drone ship.

The next Falcon 9 flight successfully delivered its payload to orbit, however no attempt to recover the booster was made on this flight.

The next Falcon 9 flight was not successful due to vehicle breakup and loss of a Dragon cargo capsule.

The 20th Falcon 9 flight successfully delivered its payload to orbit, and the booster successfully landed at the LZ-1 landing facility in Cape Canaveral.

The first landing success was in December 2015, more than five years after the first recovery attempt. And yet the Falcon 9 program was already very successful by then. After the first landing success there have been six more failed landings, and 204 more successful landings. The last landing failure was in February 2021, as of July 7th there have been 131 successful booster landings in a row.

The Starship test program seems to be starting out with a similar strategy of concentrating on flight operations first, with landing tests a secondary priority.

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    $\begingroup$ There was also the F9R Dev1 test vehicle in between Grasshopper and the simulated landings of real F9s. Which ended up not only testing vertical landing, but (accidentally) also lead to the first-ever non-test activation of an autonomous flight termination system on a US rocket. $\endgroup$ Jul 9, 2023 at 6:57
  • $\begingroup$ @Jörg W Mittag - Thanks, I forgot that the two single-stage test vehicles were not both called Grasshopper. I have edited my answer with that change. $\endgroup$ Jul 10, 2023 at 11:59
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SpaceX will not be interested in any landing attempt until they are confident that a returning starship or Superheavy is entirely capable of returning to the landing site and hovering by the launch tower to be caught.

Before that time there is nothing to be gained (and a lot to be lost in destroying stage 0) by attempting to return and Starship or Superheavy to the launch site.

It may take another two or more flights until SpaceX are confident. We shall see. But attempting to land before all of the other steps have been demonstrated would pose significant risks. An out of control Starship could easily demolish the launch tower, chopsticks, quick disconnect arm and parts of the tank farm among other things, causing millions of dollars of damage. And from Musk's perspective even worse cause delays.

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