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Nice work by SpaceX engineering.

Good summary. The booster appeared to hit the water at 1400 km/h (a bit under 900 mph) so not really survivable :-). Engine out on ship seems to left them with just enough fuel to land but not enough to do the hover thing (simulates being caught by chopsticks). They notched it down to two engines (vs planned 3) on the landing it seems?

Basically if they can figure out the engine issues, it looks like they should be able to do a full end to end flight. That's reasonable progress. Given the IPO this was a pretty important flight and I don't think they hurt it (like blowing up on the launch pad would have). So their one step closer it seems.

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Landing on two engines was the plan.

V3 Raptors are too powerful, they no longer need three engines to land. They are only going with two from here on out.

So I think it’s unlikely that they altered any aspect of the landing test due to lighting only two engines… as they was the plan anyway.

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Hmm, I've seen data that landing the booster on 2 engines was the plan, but hadn't seem similar things about Starship. The difference is the chamber pressure you need in the individual engines. Lower chamber pressure has, in the past, been easier to modulate for precise control. Do you know if they've done any white papers or patents on V3's flow aeronautics?
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Is there videos of booster crash?
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Not that I have been able to find, the 1400 km/h number comes from the telemetry on the video just before it contacted the water. Presumably one could estimate the return point if you had access to the telemetry and perhaps a platform in the Gulf might have eyes on it. Depends on how far east it got.
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I doubt it since many of the booster engines didn't seem to relight, the location of touchdown wasn't near any pre-positioned cameras (if there were any).
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And the “side effect” of polluting the ocean? SpaceX is more of a let’s only do things half way kind of company it seems.
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Polluting with what? It's mostly stainless steel and other inert materials.
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You do realize that every company so far has been doing that to every booster for every launch, right?

There's 2 options if you don't want to drop stages back on earth. You don't launch, you land the stage.

SpaceX is the company that pioneered propulsive landing of a booster. You can say a lot about them but not that they pollute with dropping stages in the ocean. Even in absolute sense that doesn't happen often and that's ignoring that they put over 90% of all the weight in orbit nowadays

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The videos were incredible. My favorite part was watching the booster flip in such clarity. Normally we don't get full view of it, let alone 4k.
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Scott Manley pointed out that it seemed to flip in the wrong direction, with one of the grid fins passing through the plume and inducing a roll. Will be interesting to hear more about that.
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The videos are great!, but the rest of it is never going to work lol, just never. Even without a rethink about how to get heavy payloads to another planet this is still good entertainment.
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why won't it ever work?
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The hardest problem in the entire design had yet to be solved. Having a robust human rated tile system that can be rapidly turned around is a huge engineering challenge that kind of breaks the whole point of the design if it doesn't work. I wouldn't be surprised if they eventually give up and go back to a cheaper throw away second stage, or throw out the tile design completely and try for some evaporative cooling approach, again.
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Bear in mind that a lot of what's happening to the tiles now is deliberate experiments to see how much weight they can shave off and how many failed tiles they can survive. Given that the vehicle is routinely surviving reentry at this point, it doesn't seem "hard" to make the tiles more robust by paying for it with added weight. The question is whether they'll have enough weight budget to pay for it? But at this point...probably? Not my area ofc.
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"surviving reentry" and being reusable are two very different things, particularly if this is to become human rated.
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Even if it landed perfectly how is it going to be rapidly reusable with all those tiles breaking and needing repair? Then if that problem was magically engineered-away through some sort of materials science breakthrough, it still makes more sense to me to keep your big ships in a space staging area and your smaller ones as atmospheric gophers.
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All what tiles breaking and needing repair? There was remarkably little visible damage this time around compared with previous flights.

There's no materials science breakthrough needed -- the shuttle used ceramic tiles successfully its entire service life. What's needed is engineering work, and that's what SpaceX has been doing.

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You know a whole the size of a quarter can wreck the entire spacecraft and make it effectively throw away? Also, you'd want to use this many times. Making a system robust while not requiring months of refurbishment is really really hard.
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The Space Shuttle had that problem because it was aluminum with a much lower melting point. It’s one of the reasons they’re using steel.

We’ve seen much larger holes than that in previous tests. Some of the control fins burned completely through.

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For some of the tests, they removed a few tiles before launch, presumably to test that. Starship did fine.
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coming back in one piece, and being good enough to use for 5 more missions are two very different things. For example, all existing reentry vehicles come back "fine" but they need to be completely remade to go up again.
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Weren't the tiles one of the worst obstacles to quick turnaround times for the shuttle? It was something like 18 months before one could be launched again, and that's if they were in a hurry.
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SpaceX has been specifically engineering both the tiles themselves (e.g. manufacturing) and the way that are used on the ship to be much more rapidly repairable than the Shuttle.
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By the end they could turn a shuttle around in ten weeks.
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Small ships are less efficient, especially leaving the gravity well. Thats the whole point
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Could you tell me more? I suppose a heavy two-stage rocket is not optimized from the point of view of the rocket equation, but I know nothing about this field.
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In short, the more stages the better to discard mass once it isnt necessary, and the larger to the better to improve the ratio of (ship+payload) to fuel.

Here is a decent summary.

https://gemini.google.com/share/121466b300c1

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This is only true to an extent. Yes, a larger rocket means a better mass:payload ratio, but a larger rocket also means more mass in absolute terms, and more mass means more fuel, and more fuel means more mass, and more mass means more fuel, and more fuel means more mass, and so on. This is "the tyranny of the rocket equation", and it places an upper bound on the size of rockets that need to carry their own fuel for a given gravity well. And because the larger absolute mass of a larger rocket means more fuel, which means more cost, it relies on actually being able to find enough paying customers to fill out that payload capacity every single time. This is why, for example, despite the existence of jumbo jets (which have a better mass:payload ration than smaller planes), most passenger flights are not on jumbo jets, because there's just not enough demand on most routes.
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While we're downing this I'd like to add I think the "I've written X in Rust" posts are also cringe :D
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Good summary. I was pleasantly surprised that they nailed the re-entry target even after the ascent engine problems.

The re-entry itself looks amazingly smooth compared to V2. TBD whether it's good enough for re-usability (much less rapid re-usability).

But Flight 12 was definitely forward progress.

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SpaceX does an excellent job at videography. Sad that Nasa flew its Artemis mission with potato cameras.
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SpaceX probably spends a lot of money on marketing/public relations creating great media. I'm guessing NASA's on a shoestring budget for that kind of thing.
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Hey, we have everyone watching, our funding might in part depend on interest and awe…

Not just space-potatoes… but missed the separation shot on the live feed. How in the hell!?

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I'm concerned about the cracking clearly visible on the heat shield tiles. It doesn't bode well for rapid reusability.
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I thought the tiles were designed for easy replacement, so not a big concern with replacing cracked ones.
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The tiles ablate. The shuttle returned from every mission with missing tiles.
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Shuttle's tiles not being durable as hoped is what killed it's turnaround time.

The problem was never solved and turned what was supposed to be a few days into weeks or months. Every mission the shuttle had to go back into the assembly building and have all tiles inspected and potentially replaced.

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Shuttle tiles were also unique per position and starship tiles have a few base forms that are interchangeable
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Shuttle tiles were also bonded to the body, which I don't believe is the case with most of the Starship tiles.
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I would also believe that a robot could inspect and replace tiles a lot faster than humans.
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Total 6 shuttles built over 35 years. SpaceX already crashed 12 over 5 or so years.

Obviously doesn’t guarantee they’ll find solution, but fast iteration will definitely help.

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The tiles are not supposed to ablate - they're supposed to be ~fully reusable. That said I think it's plausible that the much higher iteration speed and lack of a need for human-rating (at least during reentry, for now) will allow for more success than the space shuttle saw with its similar approach.
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The shuttle required long expensive refurbishment after each flight.
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Just made me realise, this is just like the F-35.

Its turn around time is ridiculous, it has to be maintained with specialized equipment/hangers, along with external contractor assistance.

Compared to the Gripen, as an example, which can land on a freeway and be up in the air again in a few minutes.

One was designed to be used in war, in desperate scenarios, with no ability to coddle it. The other, the F-35? Is designed around milking the taxpayer as much as possible, and employing people in as many politician's states as possible.

The shuttle was like that, I think. Which is really sad.

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The F-35 is designed to be able to break into and defeat modern air defense networks.

The gripen is a much less capable non expeditonary platform designed to maximize asymmetric losses if sweden is invaded. As a small country sweden has to follow a porcupine strategy to deter invasion.

Presently the actual comparable to the F-35 is attritable drones, which is why every mid-size and major power is developing them.

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The Russians have been trying to use attritable drones for years to break down the Ukrainian IADS and have not yet succeeded. Meanwhile the Israeli F35 fleet with no direct American support was able to crack open Iran’s air defenses at the start of the Twelve Day War with relative ease.
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I think there's also some exaggerations about the differing highway landing capabilities of various aircraft. [1] is a video showing Eurofighter, F/A-18 and F-35 all landing on a highway in an exercise. Capability with stores and fuel load is another thing but I've read material that doesn't find the contemporary aircraft drastically different in that regard. Now, maintenance hours per flight hour and general operability certainly are interesting topics and there could be large differences.

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

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Landing is the trivial part, though the USAF traditions of "FOD walk" do seem funny to air forces where donations you found out the aircraft spent whole day flying with maintenance toolkit left in intake.

The maintenance is the real difference - US specifically USAF gear is designed for nice air conditioned hangars to do regular maintenance, Gripen, MiG-29, and to way lower effect F-18 (when compared with F-16) - the first two assume forward bases without ability to do major maintenance, and even the latter (and other carrier adapted ones) promote things like quick swap engines because that's no space for hangar queen to have deep engine maintenance just so engine vendor can claim long time between overhauls

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The main reason the Mig29s have a reputation for easy maintenance is because they don't replace parts, they just throw away the whole airframe. The structural and engine service life is like 1/10th that of western fighters.
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Not really. This "reputation" is based on misunderstanding of differences in doctrine.

The engines did have lower overall hours, yes, but the suggestion they need whole overhaul after very few hours is because it looks so when looking at it from USAF doctrine where "removing engine and sending it to special facility" is only for rare complete overhauls, and local mechanics are supposed to do regular minor work all the time.

MiG-29 instead was done under doctrine that the airbase does not have mechanics capable of doing such overhaul, nor the facilities to do so, and instead you swap the engine and send the used one to maintenance facilities further away from the front, same with other aggregates.

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Agreed and specifically in the case of the Gripen the “test condition” was “Needs to be serviceable by a few conscripts working under the direction of one person who knows what they are doing”.

It’s an extremely different design goal, the US doesn’t mind exotic weapons that require exquisite (and expensive) methods of servicing, they have the budget and the assumption that a well equipped air field will be immaculately maintained.

Meanwhile the Mig-29 designers assumed it’d operate from damaged/poorly maintained fields, so on the ground you can shut the primary air intakes and it uses ones on top of the plane to get air, drastically reducing the FOD risk on taxi/takeoff.

I do wonder how well the F-35 would fare in an actual shooting war against near peers when all the peacetime assumptions breakdown.

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That's a reason the Mig-29 is no longer in production. Point defense fights are obsolete.

The F-35 was just in a war, in Iran. It performed as expected and was able to roll back Iran's air defense network in days.

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>It performed as expected and was able to roll back Iran's air defense network in days.

"Rolling back" Iran's air defense seems like very fuzzy phrasing. Certainly, Iran was not able to close its own airspace, nor prevent ongoing airstrikes on many American and Israeli targets. At the same time, my armchair observation is that a great many US and Israeli airstrikes were accomplished using stand-off weapons [1], which would not have been needed if the United States and Israel had achieved 'air supremacy'[2] as has been the case in America's conflicts in recent history.

The observed trend in USAF readiness has been downward for some time [3][4]. Air war is more than single sorties. If you have anything resembling an accurate summary of sorties flown, targets successfully hit, and number of combat-ready aircraft throughout the (currently on hold) war, and so on, please share. Absent such detailed information, all we have are various degrees of speculation.

1. https://news.meaww.com/us-used-tomahawks-himars-standoff-wea...

2. https://en.wikipedia.org/wiki/Air_supremacy

3. https://www.airandspaceforces.com/air-force-mission-capable-...

4. https://havokjournal.com/culture/military/the-hidden-erosion...

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Well, every mission that it returned from it had missing tiles. That is not the same thing as returning from every mission.
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I mean ... step 1 is probably fixing the part where it lands in the ocean, falls over and explodes. Once they've done that and can get their hands on the tiles I'm guessing they can continue to iterate there until they get a more easily reusable design.
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That part was intentional
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Dang, a random HN user solving all the world's problems yet again, what would humanity do without you random HN guy?
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Fantastic summary. Thank you!

They've made great progress but have a bit left. It's always the last mile, isn't it?

It's so cool seeing progress in this space (sorry).

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“seems to have hit the water harder than expected and was very off target.”

SpaceX’s people were saying it was on target, and it seems to have landed in about the same position relative to the camera buoy as previous flights. I don’t think there’s any evidence to call it off target. The landing and toppling looked the same as previous flights too.

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You've mixed up the ship and booster.
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Yep, I did. Thanks.
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I think the ship really punted the booster during stage separation. And caused the boost back failure from sloshing.

Also I think Ship now has methane thrusters on it. They were operating with a clean blue flame in short purposeful bursts.

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If we look at the venting from the propellant tank (around T+16:15) it looks thick white closer to the vent, becoming more transparent and blue as it expands. That's just sunlight scattering on the particles and density fluctuations in the flow.

A good cold gas thruster produces a lower density, more expanded flow, which looks blue for the same the reason the sky looks blue.

One can compare this to the exhaust from various Falcon-9 engines and thrusters when it is illuminated by the sun on the backdrop of the night sky: https://youtu.be/JRzZl_nq6fk?t=193

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From what I've read there was "unintentional mixing of fuel and oxidizer" which caused a fire in the engine section, so the engines automatically shut down. I don't thing we have official word yet, though.
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The final issue that led to the scrub was that a pin that held back the QD arm got bound and would not release.
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Thank you for your service! You nailed every single detail.

This was as good, if not better, than the livestream itself!

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Did the landing burn light two engines as expected? It happened fast, but the graphic made it look like only one lit. If that’s true, that would be impressive as only lighting two was meant to be a test. At least according to the live stream hosts.
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Booster is a totaly new rocket. It did launch with acarity and by any other standard did well, but the failure to relight could be anything, but I am going for the giant fuel feeder tube bieng the failed part, based on nothing more than how tickled they were with it,and tank baffling bieng a dark art. The slosh of the fuel durring the flip is going to produce an internal tidal wave, lots of stuff gets "tested" there.
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[dead]
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Lots of engine failures. Doesn't exactly bode well for a company looking to go public immediately. One of the engine failures was not on the booster but Starship as you noted, and that is a bit unexpected. I don't think they have spoken about it being equal in capability with one engine out, right? Those engines don't move around to compensate IIRC.
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Not sure how you come to that conclusion. The capabilities can overcome loss of engines. The fact it was successful with loss of engines shows it is working as designed.
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No, it just means the mission happened to be salvageable because of its parameters. The booster is designed to have engines out and can compensate because it has so many engines and many of them are on gimbals. On starship, the vacuum engines aren’t on a gimbal. I’m not sure how it could compensate for one of three engines being out.
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Some are on a gimbal and they specifically talked how others gimbaled out a bit to compensate. This is specifically something they designed in and not an accidental lucky save. In this flight they didn’t intend to test “one engine out” feature but it worked out that way.
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See my other comment. The vacuum engines are NOT on a gimbal. None of them. The sea level engines on starship and several of the engines on the booster are on a gimbal. But not the vacuum engines for space.

EDIT: I cannot reply further in this thread, but my understanding is that the non vacuum engines are not intended to stay lit throughout the orbital flight in a typical mission. If they are, they can gimbal and compensate.

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> The vacuum engines are NOT on a gimbal. None of them

I said some raptor engines are on a gimbal, not vacuum engines.

To be precise, the three central engines can gimbal up to 15 degrees. That can control the thrust vectoring when an engine fails, and that’s what happens in the last flight.

Since the flight already happened and we know it didn’t spin out of control (unless you imply their diagnostic and telemetry was completely off and the engine was actually on) something must have compensated for the failure. It wasn’t magic, it was in fact the central 3 engines that did that.

You may be confused because those are called sea level engines, but that doesn’t mean they can’t work in vacuum.

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I think previous comment means "on a gimbal" as in "angled at a non completely prograde direction" (presumably angled such that each engine points through center of mass so that none of the engines impart a torque)
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The person you’re replying to is trying to play rhetorical word games.

The upper stage has six engines. The outer three engines are “vacuum engines” (optimized for operation in space). The inner three engines are “non vacuum engines” (optimized for operation in the atmosphere, at sea level).

The outer three vacuum engines are not gimbaled, but the inner three sea level engines are. Thus, it is completely accurate to say that they gimbaled some of the engines to compensate for the engine failure.

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They explicitly said that they have engine out capability on the ship in the stream.
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That’s for the booster (the big lower part) not for starship (the upper part that continues to space). They were surprised to have a vacuum engine out. In space there’s no atmosphere so you can’t use fins or wings to change direction. And if the engines can’t move around, you only have thrust and gravity and the tiny attitude adjusters to direct your ship.
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You're simply wrong. The non-vacuum-optimized engines on the upper stage are still functioning in a vacuum, and their ability to gimbal to offset the loss of one of the vacuum-optimized engines was planned for.
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Watch the stream again starting with the ship burn. They explicitly said they have engine out capability on ship. The sea level engines on the ship are running and gimballing.
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The takeoff looked almost normal but I noticed a slight drift from vertical, likely because one of the engines was dead or dying. Overall the V3 is supposed to be an upgrade but actual progress is more or less stalling compared V2.
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It is supposed to tilt away from the launch tower immediately, you can see this on previous flights. This keeps the engine plume away from the chopsticks and top of the launch tower.
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Also an additional goal is to get the booster as far away from the pad as immediately possible in the event it falls back down.
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The payload (100t) is at least double that of previous flights. It’s largest spacecraft ever flew. That’s some stalling
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There is a slight tilt normally, but I agree it was more than usual.
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> The amazing views of the plasma during re-entry, something never seen live before starship, are now routine.

The word "live" is doing a lot of work here. Astronauts used to film the plasma going past the windows of Shuttle.

I remember as a kid my science textbook had a still of it to illustrate plasma.

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> The word "live" is doing a lot of work here

A latency of a few seconds for streaming video compared to several months for a still photo from the Shuttle seems an entirely valid use of 'live'.

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The difference here is a matter of AV technology improvements in the last 40 years.
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The difference is having high-bandwidth signal pointed up / away from the wall of plasma.
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