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by amarant 22 days ago
Oh hey, you're right! Somehow I read "water landing" and interpreted it as landing on one of the barges (ocisly or jrti) any clue why that isn't the case? Is super heavy just too big for the barges maybe?
3 comments

They won't use barges because the booster has no landing legs (to save weight), and because the booster is massive compared to Falcon 9. Also Starship is meant for rapid reusability, and it can take days to return a barge to port and unload the booster. Getting barge landings to work would be a distraction from the goal of Starship, and SpaceX already has Falcon 9 for current payloads.

And they won't attempt a catch with the first V3 booster because it's not worth the risk. They can build a new booster every couple of months. It takes much longer to build the launch/catch tower, and they don't have any spare towers yet. A catastrophe during a booster/ship catch would set them back a year, so they'll only attempt a catch if they're confident it will succeed.

I agree with everything but nitpick: SpaceX currently has two launch/catch towers in Texas, and they are building a third in Florida.
Only one of them is working right now. Their original tower needs to be overhauled to support Starship V3.
It doesn't have landing legs so it has to be caught by chopsticks. They're skipping the barges; either it lands back at the pad or it doesn't land.
Superheavy is 10x larger than the Falcon. Its thrust would sink the barge.
Yeah. Rocket first stage Approx. unfueled mass:

Super Heavy: 200000 to 280000 kg

Falcon 9 first stage (without Falcon Heavy side boosters): 25600 kg

So 200-280 tons. A standard barge can support 1500-3000 tons of cargo. Even with the added weight of a catch tower and a healthy factor of safety thrust isn't gonna sink the barge. Far more likely the major hurdle would be stability issues with how tall it is.
It's not 280 tons... it's a falling object with kinetic energy so that rocket thrust is going to be very problematic for that boat especially if it' hitting unevenly.

That and there's no way for it to stand without a catch tower.

Hypothetically, what's the effect of that much thrust close to a water surface?

I.e. if they cut a hole in the middle of a barge and it was burning at touchdown "against" the ocean

I imagine water doesn't have the kinetic problems that chunks of concrete do, but also that's a LOT of energy for even water, so maybe there'd be steam issues?

Well the idea would be to put a catch tower on a barge so those aren't actually issues.