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Comment by Aeolun | Hacker News Reader

It can’t be that hard to not land it in your launch area right? Can’t they have a separate land and crash area (preferably separated by a few tens of kilometers)?

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You would need to build a second tower with catch arms there. The booster does not have landing legs and will not touch down on the ground, the plan is to have it settle on the same "tower arms" that are used as a crane to stack the booster and the ship for launch, with engines still well above ground.

They managed landing legs and they decided to up the level of difficulty a few notches or something?

Pretty much. Catching it with the launch tower means in theory you can have much faster turnaround between flights, since you don't need to transport it from the landing site to the launch site.

It means less hardware/weight on the actual rocket.

And crucially more room to absorb shock.

It's true that SpaceX's previous landings have used legs, but that's either been Falcon boosters (much smaller/lighter than Starship boosters, AKA "Superheavies"), or for Starship's upper-stage (again, much smaller/lighter than Superheavy boosters).

The catching system looks crazy, but it might actually be easier than landing a Superheavy on legs. The ground is a larger target than the catching arms; but its maneuverability and shock-absorption are famously low.

Landing legs are heavy, because they need to absorb a big shock. They also need actuators. "The best part is no part"; if there is a way not to drag this extra weight from the sea level up to the stratosphere and back, it counts as an improvement.

It's a good question, and I don't have a great answer for you other than my understanding is that the ground space they have to work with in Boca Chica is not really that large. And there are a lot of environmental concerns (+ the chances of blowing up on landing is greater than blowing up on liftoff).

But I've heard speculation that they might build a dedicate landing tower around their Florida launch site for that reason. No idea how accurate that is though.

It's about weight. The landing legs on the Falcon 9 first stage make up 10% of the dry weight if I remember correctly. 10% is huge savings for a booster. They've already proven they can do pinpoint landings so moving the hardware to the ground makes a lot of sense. Also, the booster should be easier to control because it can hover (the Falcon 9 booster has to do a suicide burn because its near empty thrust to weight ratio is > 1 even with only one engine). They wouldn't want to hover because it's a big waste of fuel to rely on that but it is an option while they are still practicing the catch maneuver.

They are building a tower at the Cape (it's fully erected already) but people have noticed the arms on it are shorter leading some to speculate that it might not be used for catching.

Long term it’s better to have launch and landing on the same tower, if the goal is to rapidly reuse the rocket.

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