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Starship survives reentry during fourth test flight (spacenews.com)
58 points by lordwiz 741 days ago
6 comments

If you haven't seen the video yet... it's amazing. The re-entry in particular had amazing footage. Looked like something out of a sci-fi movie.
Definitely the coolest space video I’ve seen yet! Watching the plasma burn through the flap towards the end was unreal
Could you provide a link?
This is the official stream.

https://x.com/i/broadcasts/1OwxWYzDXjWGQ

If you prefer youtube, these are probably the best 3rd parties:

* Everyday Astronaut: https://www.youtube.com/watch?v=8VESowgMbjA

* NASASpaceFlight: https://www.youtube.com/watch?v=mTkhv4fvOgA

I'm on a work computer currently, but search on youtube "everyday astronaut starship ift-4" or similar.
It is frustrating that SPX wont stream these on youtube themselves. I think I counted 4 or 5 fake streams with a total of 1m viewers that were just bitcoin scams. Everyday astronaut and nasa spaceflight seemed to be the only ones with legit streams.
It's almost expected with Elon owning X. The platform may really have the ability to challenge Youtube for live video things. The infrastructure and dev capability is there. It may well reach the value that he paid for it....
I hope so. Seems like youtube is decaying is it goes for more of a tik-tok style approach and with loads of AI spam. Doubt Twitter will be any better on this though :-/
It seems to work great for live content, but doesn't seem to allow for rewatching. Hence people here in the comments linking to YouTube videos.
They streamed the first one on YT, but have since moved to Twitter

https://www.youtube.com/watch?v=-1wcilQ58hI

Has SpaceX shared plans on where Starship goes from here? Other than the minor hiccups (a couple of engine misfires; a damaged flap), this looked like a wildly successful test. I'm especially curious to know when they'll start successfully recovering the booster and Starship.
The engine failure was minor, true. That's the design point: if engines have a firm ceiling to reliability it's better to design so that one or two can fail than to put all the eggs in a basket. And indeed, the 32/33 engine set was enough to hit the trajectory targets, so that worked great.

But I don't think you can characterize a burned-through flap as minor. Once there's a hole in something like that, the fact that it remains aerodynamically usable is just dumb luck. Clearly the heat shielding failed. If this were a production craft you'd probably have to scrap it even if you recovered it successfully, defeating the whole point to having it be reusable in the first place. The shielding folks have work to do.

But at the same time, the telemetry and control folks are popping champagne. Their stuff worked magically. We literally had live video (albeit through a cracked lens from all the flap debris) all the way through reentry to spashdown, and the landing maneuver looks to have worked perfectly.

> But I don't think you can characterize a burned-through flap as minor...

In prod, a localized flap burn-through would be a Major Incident.

Vs. in dev...what competent manager would be bothered if the some bleeding-edge beta code dropped 10% of packets the first time that it faced a full-load test?

That sort of depends on context. If the failure was reasonably expected, like for example your router is running on prototype underclocked hardware or is a debug build that is known not to have the final performance characteristics, sure. But if it fails and you don't immediately suspect why it failed, then that's a sign of a genuine design flaw.

And sure, it's good to find the design flaws in "dev" vs. "prod", but it's still bad to have them.

In this case, we don't really know what the expected performance of that flap shielding was. Maybe it was a kludge and they were just hoping the glue held together, maybe it was a finished design they just thought they were validating. The latter is a much (!) bigger problem than the former.

Per Wikipedia, SpaceX's 3 "Get out of Mishap Investigation, Free" cards from the FAA for this test flight were -

Starship burns up during reentry

Flaps lack sufficient control authority

Raptor engines fail to relight

- suggesting that both the flaps and heat shielding were regarded as highly experimental, and failure(s) in them very likely to occur.

Def super successful. Crazy how the flaps held given how they seemed to disintegrate on re entry. They said they’d try and catch the booster for flight 5 if the booster splashed down successfully this time and it did so fingers crossed. That’ll be a pretty wild thing to see. Could happen soon too. Next flight might be within about a month.
Everyday Astronaut speculated that we may see a catch attempt next and that next flight could be as early as within 2 months.
The internet is weirdly quiet about this achievement
Yet one flap is going to be eternal in human memory
One flap we know of, it is quite possible its counterpart suffered the same fate. No matter, the ship remained manoeuvrable and performed the landing flip even with half a flap - or half of two flaps - missing. That is valuable data which shows the thing can survive such damage without losing control. Now they'll need to find some way to better seal those hinge areas from the 20 minute plasma torch it is subjected to during re-entry.
Aptly dubbed Flap Norris.
depends on your bubble.

my X is full of leaking flaps.

It seems like a lot of people are making too much out of the fact that the ship survived re-entry. On a test flight, the difference between “the heat shield failed around the flap causing severe structural damage, but it held together enough to make it through re-entry” and “the heat shield failed around the flap ultimately resulting in a RUD” is not particularly significant. The implication for both is that there are major engineering challenges yet to be solved for managing re-entry. Don’t get me wrong, this was a successful (and wildly entertaining) test flight and I think SpaceX will get re-entry sorted out.
Discussion [0] (257 points, 4 hours ago, 332 comments)

[0]: https://news.ycombinator.com/item?id=40596883

mark things as [dupe]

wasting our time if not

So what now? do they go recover the capsule from the ocean? Did it land near where it was expected? Or are they just sinking stuff in the ocean?
For now, yes. Just sinking stuff in the ocean.

The reason for this is they first need to prove to the FAA they can actually control these vehicles and land them when, where and how they said they would before they will be approved to try the maneuver over land.

The entire mission profile at this stage is just about proving out that it works and it will be safe to try put it down on land without risking hitting a building with a skyscraper sized stainless steel rocket.

Telemetry was as intended throughout the flight so it presumably landed where intended. They trigger an abort after splashdown, so the rocket explodes then sinks. And yes the remains, which is mostly just steel, then sinks into the ocean.