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Comment by strangesmells06 | Hacker News Reader

Gotcha! So this test criteria this weekend may not be to reach orbit, but just test out heavy booster and getting starship correct trajectory.

If they crash into the ocean do you know if they are supposed to be recoverable or will they sink?

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Best case, they get to test the new sound dampening, armored pad, armored pad cooling, igniting all the engines on the pad, booster launch, staging, booster fly back, booster descent, booster landing (though not on anything solid). If that works they have a booster floating in the Gulf of Mexico they need to clean up.

For Starship they get to test staging, engine in vacuum, bellyflop control from very high altitude to sea level. Apparently all the way to sea level. They do not appear to be planning the reignition and flip. They may set the record for "most powerful bellyflop".

All the excitement is in the first 9 minutes of the flight. A little over an hour later the Starship's "orbit" will intersect too much atmosphere and will re-enter for about 12 minutes.

As for why not to try landing the Starship on water, I think they'll play with all their available fuel mass in vacuum. Those engines haven't operated there yet.

I'd be surprised if they haven't tested at least one engine in vacuum. You can build a test apparatus for that. Only learned how when I saw this video: https://www.youtube.com/watch?v=hrLyzpTV7GU

The planned nominal trajectory for the first flight (and, I presume, this one as well) set Starship up for re-entry without a deorbit burn, so they're not planning to properly enter orbit at all. This is to avoid the prospect of an uncontrolled re-entry after orbital decay if something went wrong while it was in orbit, or worse if it got up there and the tanks exploded. Elon doesn't ordinarily choose to be cautious like this, so it probably wasn't entirely his choice.

(They'll be putting out enough energy to demonstrate that it could enter orbit, but the trajectory that they'll be putting it into is an "orbit" that intersects the atmosphere.)

Starship will crash into the ocean at terminal velocity off Hawaii (with no belly flop maneuver to stop descent right above the ocean), there may be some floating bits but not recoverable in any significant sense. The booster will do a landing burn, they will most likely sink it in the gulf and not attempt to tow it back to port.

https://www.spacex.com/launches/mission/?missionId=starship-...

It is not supposed to be recoverable for reuse.

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