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Comment by guardiangod | Hacker News Reader

In the previous tests Spacex used 2-3 rocket engines for the initial landing burn.

For SN15, the rocket used 2 engines throughout the landing procedure. I wonder if this is a sign of their confidence in the improved design.

The landing was smooth as butter and nothing went noticeably wrong, although I did noticed that the rocket landed dangerous close to the edge of the concrete pad.

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They actually did it. Lot of work left, but this is the big fence to jump over. The bellyflop and landing is no longer a theory or a hope, it works, with real hardware, in the real world. Rocket go up, rocket come down, rocket still standing. What a thing to see.

Previously as well: Rocket go up, rocket come down. Rocket still standing.

But the difference with Starship is the amount of fuel burned to slow it down.

I think the real success of Starship was proved a few launches ago - flip maneuver, belly flop and coasting on the belly to slow down sufficiently. Landing took a few tries but it was relatively a smaller success compared to the aforementioned aspects demonstrated during failed attempts to land.

Didn't it explode a few moments after the other "successful" landing though? That doesn't really count. My understand is this is the first fully successful landing of Starship with the flop maneuver. Might have missed one though.

I think they were supposed to fire all three engines and turn one (or two?) off if they all start fine, but in the video it looks like only two engines started. Not sure if that was intended, or if one of the engines failed to light.

That is what I recall from the prior failures, and what they said they were doing to mitigate. Interesting to see only two lighting.

There was also quite a bit of fire after the landing, but this time the rocket would not explode from it.

Fire and a few pops/pings/small explosions in the engine area, but didn't appear to destabilize the rocket, which is a good sign.

SN10 blew up from the post-landing fire, because it landed hard, collapsing the landing legs, skirt and damaging/destroying the engine bells and more stuff around them - possibly the thrust bulkhead and bottom of methane tank, leading to significant leaks and eventual explosion. SN15 seems to have landed intact on fully extended landing legs, so the hardware inside the skirt likely survived, and whatever caused the fire was a (relatively) minor leak and not catastrophic.

Man did you notice how close on of the legs came to missing the concrete pad and ending up in the dirt? It looked like just a couple feet to me. It would have probably tipped over.

It slid sideways about a meter on the pad. I believe yesterday had the highest winds in any of their Starship launches.

Could also be that these Raptors are able to throttle back more deeply. Just a guess though.

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