SpaceX Starship rocket explodes minutes after launch from Texas

I think it's clear one of their biggest lessons is that the construction of the launch mount is wrong, and it REALY needs a flame diverter. Take a look at this photo: https://mobile.twitter.com/LabPadre/status/16490627841670307...

That massive hole in the ground should not have happed, and I suspect that was not an expected possibility. It is a very costly mishap and could mean completely rebuilding the launch mount. With the excavation and rebuild, that could be months or even as long as a year.

On top of that there was significantly more debris making its way to South Padre, the political fallout (pun intended) will be significant, and could cause issues with launch licenses going forward.

SpaceX: We expect the vehicle to reach 40km at which point it will probably blow up.

FAA: Ok but what if it doesn't blow up?

SpaceX: Well I suppose we could separate the stages.

FAA: And then what happens?

SpaceX: Well I suppose we could try to land the first stage and launch the second stage into the ocean...

etc etc.

The launch pad is not in great shape either https://twitter.com/LabPadre/status/1649062784167030785

Whereas SpaceX is more like Kerbal Space Program in that if it blows up, at least you're having fun.

And while they had some failures early on with their early rockets, the Falcon 9 is now a very reliable craft that's done dozens of successful missions, successful recoveries (which I think they still consider a bonus rather than a goal) and re-uses, and a streamlined launch process, which has become more economic - and possibly profitable - over time.

I will add "possibly" profitable though, given that it feels like the majority of their launches is for their own Starlink project, which is costing them billions - but it's a project to ensure use and reuse of their rockets, instead of the company going stale waiting for customers.

In the SpaceX feed they were waiting for the second stage to separate and light, and it didn't do either. So first question is why didn't it separate? I think that is the relevant one because I would expect them to have interlocks that would prevent the second stage from starting up if it were still attached to the booster. The interlocks would explain not starting up the second stage engines.

One anomaly I noticed was that the booster did not appear to shut down 100%, ever. If that was the case, that would be important because the onset of "zero g" from engine shutdown is a well tested way for the next stage to know that the stage below it has stopped firing.

Some (many? all?) spacecraft rely on the physics of the expended boost stage being much lighter than the remaining stack. This disparity means atmospheric drag on the lower stage has a bigger effect than it does on the upper stage. If the second stage retention system "lets go" when it detects zero-g, then the two pieces will begin to separate, slowly at first, and then faster when the very un-aerodynamic opening to the top of the booster gets into the slip stream.

Depending on how the second stage interlock works, it could be timed (wait t seconds and then light up) or radar (wait for distance between first and second stage) or some communication between the booster and the stage. By time is cheap, but risks a slowly separating booster being "too close" and having it become damaged from the blast of the vacuum engines starting up. Radar is likely most reliable (and most expensive), and comms would work by there is a lot of ionization going on at that speed that makes them more difficult.

So questions I would look at; First, if all the raptors didn't shut down, why not? Second, did the booster attempt a rotation and re-entry burn with the second stage still attached? Third, is there a way to "abort to orbit" this scenario where the second stage decides to let go and light up even though the first stage hasn't shut down?

Fun to watch though, its a pretty amazing rocket and that they didn't have 4 (or 5) of the raptors firing when it started off was another thing to look into. On pad aborts are a thing too, but as the parent states, there are faults that you won't get any useful data, and those you note and continue on through. I think the non-start of the raptors was of the latter.

Raptor engine development started in 2012. Starship's development started around the same time. They now achieved max Q and got flight data all the way to booster separation. On real, flight ready hardware. By an all-American team started right here in California using private funding from an already profitable all-American privately developed launch platform (the Falcon 9).

This is in contrast to the SLS and it's predecessor the Constellation program (the SLS really being an evolution of the Ares I and V) that started in 2005 and, so far yielded a single successful test flight. Almost 30 billions sunk in "research and development" (for Shuttle derived hardware?). Excluding launch costs.

Or even really the crown jewel of the European Union, Ariane 6, a technological dead-end delayed once again and already 15 years behind the Falcon 9.

Uh, yeah, about that...these commercial space flight companies are less than awesome about correct flight plans. Virgin Galactic, for example, wildly blew their flight plan on the flight with His Sirness aboard...and suffered zero repercussions for it, I might add.

What does this mean?

first time in a long time a rocket of this scale (number of engines) since N1 has been made

I fully understand that rocket launches are going to fail a few times before succeeding, I don't get the need for gaslight.

This feels like North Korea style propaganda.

> so the only way to test x is with a starship on top.

Why did they have to test "x" now? We don't have to go multi decades between launches, but couldn't they have delayed and tested when they had a more reasonable chance of success?

Maybe after building a flame trench/diverter too.

That sounds logical, but isn't really a thing in aerospace/space. Complicated high-energy systems have thousands of failure points. So to have any chance of success each failure point needs to be engineered below, by way of example, a 0.0001% chance of failure. That costs lots of money. But say one decides to accept more risk for less cost. Ok. So you switch from 0.0001 to 0.001 failure rates. You risk is now 10-fold higher at each failure point, but with thousands of failure points adding up you are now essentially doomed. And you haven't saved anything. The cost of 0.001 components isn't fundamentally different than the 0.0001 components were. SpaceX can save money though different business practices, by trimming people/money/contracts/compliance and such, but if you look at their rockets they are not fundamentally any less-perfect than anyone else's. They cannot afford to be. This is why rocket failures, like aircraft failures, are taken so seriously. There is an extremely fine line between "works ever time" and "never worked twice" with very little money to be saved between the two.

Across many areas, risk-v-cost math never really happens. It is either go or no go. Take CPU production. Intel spends billions at each of hundreds of fabrication step to push down miniscule error rates because any of a million errors can destroy a chip. There is no money to be saved by allowing any one process to become less than as perfect as it can possibly be. A detected slip from 0.0001 to 0.001 at any step would result in an entire fab being shut down in order to diagnose the problem. The marginal savings of a less-than-perfect process isn't worth the exponential increase in the risk of total system failure.

https://austinkleon.com/2020/12/10/quantity-leads-to-quality...

[A] ceramics teacher announced on opening day that he was dividing the class into two groups. All those on the left side of the studio, he said, would be graded solely on the quantity of work they produced, all those on the right solely on its quality. His procedure was simple: on the final day of class he would bring in his bathroom scales and weigh the work of the “quantity” group: fifty pound of pots rated an “A”, forty pounds a “B”, and so on. Those being graded on “quality”, however, needed to produce only one pot — albeit a perfect one — to get an “A”. Well, came grading time and a curious fact emerged: the works of highest quality were all produced by the group being graded for quantity. It seems that while the “quantity” group was busily churning out piles of work – and learning from their mistakes — the “quality” group had sat theorizing about perfection, and in the end had little more to show for their efforts than grandiose theories and a pile of dead clay.

Yes, but let's not take the analogy too far. For people who work in safety-critical design (including software), it takes a different mindset than what is often prevalent in silicon valley. When the stakes are high, you don't really want to "move fast and break things".

You can actually see this in SpaceX. In development when stakes are relatively low (e.g., no payload or passengers), the risk threshold is high. But they start taking a more measured approach when that risk starts to ratchet up. The danger being, advocates of one approach don't always know when/how to transition to the other.

edit: Never mind, it's slightly less – see the comment below correcting me. The SLS program has 40, not 34, RS-25's.

Where in the past, people would be like "OH NO!!" -- but the crew knew how much data they got out of that launch.

I wonder how stripped down the starship was though in an effort to save costs in the event such as this RUD.

I would love a piece of the shrapnel from the exploded device though...

Hopefully they get those pieces and auction them off.

You’d think NASA would have read their own studies and given up rather than proceed on the predictable Artemis boondoggle.

The initial launches are gone be more like 5 billion. Its pure fantasy that it will go to $2 billion anytime soon.

That is not always a bad thing. I mean you typed this on a computer running an ISA that started in the 70's or 80's. Maybe 90's if you are on PowerPC ;)

SpaceX doesn't have a test stand where they can static-fire the booster at full power or duration, which feels like an interesting gap in their usual 'hardware-rich, test-often' iterative approach. I'm betting we see something like that roll out soon.

One I find most impressive?

Weight of Starship when fueled: 11 million pounds

https://www.youtube.com/watch?v=gMbUeO4iGhY (Why SpaceX Cares about Concrete)

This probably explains why some of the engines didn't make it off the pad. That is some incredible damage.

https://www.youtube.com/watch?v=thA8jlgcJ-8

Better view of the hole and damage to the launch mount

In summary yeah, this launch was a massive success!

Almost none, because "software engineers" aren't _actual_ Engineers! (ducks for cover)

But really, this was a huge step in the right direction on the cutting edge of propulsion science and spaceflight.

SpaceX will iterate and in a few months/years everyone here will be telling you how "they always knew it would work" and "starship succeeding was obvious"

You can not be a fan of Musk the person and still appreciate stuff like this.

So I mean, if you want to argue that HN doesn't have enough "weird nerds crawling out of the woordwork for any opportunity to cheerlead their heroo Musk" it's a point that appears to be refuting itself.

The minimum goal was to get the ship off the pad and not having it explode near it. The maximum goal was to achieve separation of stage 1 and reaching orbit. Discussing why the maximum goal was not reached has nothing to do with negativity, but is the natural thinking of an egineer who mainly tries to solve problems. So we naturally think about the ignition failure of some of the engines. Was is caused by the (obviously larger than expected) damage of the launch pad? Or is there a problem with reliability of the engines? Also, will the damage of the launch pad cause a delay for the next start? How can this be improved? These are all things that we are trying to find answers for fro our armchairs.

I would wager that a good part of that is just a reaction to the over-the-top "massive success!" posts.

I am confused. Everything I read before the launch said that it was intended to reach orbital altitude and make it around the Earth.

I will disagree with you though and say that the rocket stage separation failed to work. And this occurred a few minutes after launching.

What would your headline be?

But seriously what a terrible title. This was a huge accomplishment in engineering, getting it this far up.

Whether they’re truly happy with this result probably will depend on their analysis of what went wrong.

If they can find the cause and it’s easy to fix, they’ll be a lot happier than when they can’t figure out what went wrong, or when they can figure it out, but preventing it requires a huge redesign.

But yes, this is the nature of rocket building. Things do get boom fairly easily.

That's not what they said in their mission presentation though. It was supposed to launch, separate, return the booster back, then the rocket was supposed to orbit once around the Earth and then fall into the ocean.

I understand people have their feelings invested into this (for whatever reason), but objectively speaking that was not what "success was defined as".

The Soviets had the 'launch often, fail fast, learn faster' view that SpaceX employs today.

However, nobody viewed the N1 launches outside the Soviet Union as successes. I'm glad to see that 'fail fast, learn faster' is finally part of American aerospace engineering.

"I may have crashed the car into the neighbour's house and broken my arm, but I did get the milk from the store!"

E: convery's reply below makes much more sense.

5-6 engines were gone since very early in the flight, and for most of those I suspect that’s because they were damaged by debris from the pad. Everyday Astronaut’s live stream had a different camera angle on the rocket, and you could see it actually slide sideways away from the tower a bit in the first few seconds. Uneven thrust would explain that.

Elon said in the past that the rocket will leap off the pad (thrust-to-weight ratio of 1.5 or 1.6 iirc). But if you’re missing 20% of your engines, that ratio is ~1.2, or less than half the expected acceleration. A slow start indeed.

What does this mean?

It's historically different in US aerospace, but not Soviet aerospace.

It’s one thing to feel defensive about a misleading headline. This is just fanboyism.

My guess is the biggest issue is the destruction of the pad. Building it up so that it doesn’t get destroyed by each launch will be a very expensive challenge.

Nevertheless both the SpaceX and NASA approaches to this are valid engineering approaches.

Whether this particular failed launch is a long term success remains to be seen. If the next 5 Starship launches all explode, maybe the NASA approach of get it right first is the way to go when it comes to space flight.

In all seriousness I don't follow space stuff much so I give the benefit of the doubt when 99% of posters give rave reviews... but I also know who is in charge of this company and the same thing was happening with Tesla a few years ago with every announcement/demo getting 99% of HN people giddy and just a few shouted down people saying "but..."

I'm intrigued as per cause. Lots of Engine failures and spewed parts. It had a real slide on liftoff. An engine violently flashed and went pop about +25s.

I do have to say, the thing requiring FTS after a violent flip well above supersonic speaks orders about structural work.

All, really ? What about the flight plan ?

I like the American philosophy to see the good part of experiences even when thinks don’t go as planned, but IMHO I feel like it's drifting more and more from « there’s good in failure » to « let’s call everything a success ». May be wrong, just my European point of view through the transatlantic optic fiber.

Generally Merlin engines on the Falcon 9 are incredibly reliable. In over 200 flights there were only a couple of engine failures. Some worked nominally on accent but had some failure during landing.

> How many do they anticipate regularly?

The vast majority flights should never have an engine out. This is something that should generally never happen. I think SpaceX would hope that far less then 1% of flights have an engine out issue. Anything else I don't think they would consider acceptable.

SpaceX will redesign the Raptor engine as often as they have to to get the reliability to Merlin levels.

At least once they lost the booster when they were planning on recovering it because they had to run the ascent phase on only 8 engines and burned enough extra fuel the booster didn't have enough fuel to complete the boost back and landing.

It is also worth noting that liquid methane is not explosive by itself.

The explosion at the end was the Flight Termination System. In case of uncontrolled flight you detonate the rocket to keep it from flying somewhere dangerous.

But it might also have been manual intervention.

Edit: "that" = one flip; not the many we saw today.

Waterfall of propellant-falling

So all-in-all, he seems to be doing great. The one thing that is worse is that replies show now mostly people with blue checkmark instead of tweets with a lot of likes or followers.

Starship is unique in that it has so many engines, which add redundancy. They can (re)start engines mid-flight.

With the loss of 5 engines, this demo flight would have been fine. Though they will have some work to do on reliability.

Control can be maintained with very few engine. I depends if its center engines or outer ring. Only the central cluster can gamble, 2 or 3 of those should be able to handle to rocket depending how full it is.

With only outer engines the could use differential thrust but the rocket isn't really designed to do that.

The Soviet N1 used differential thrust only. SpaceX prefers gimbled engines.

well..at least 8 engines failed on the way up. At least a majority of them were lit!

There was lots of very heavy debris that left the pad and flew hundreds of feet away upon ignition; I have a feeling that some debris came back up and hit an engine or two.

These people are pretty easy to ignore if you don't venture into certain parts of Twitter and Reddit. Who cares what they're social media-brained minds think. It's just another hot take.

But an actual kick-ass display of engineering prowess in recent memory was launching and deploying the Webb telescope.

- https://en.wikipedia.org/wiki/Space_Shuttle_Solid_Rocket_Boo...

- https://space.stackexchange.com/questions/5775/how-are-self-...

tldr: shape charges for solid boosters, dumping fuel for liquid

It didn't destroy the launch tower, and that's what counts!

From the video it looks like the stages failed to separate and the rocket started tumbling. I'd expect the range safety officer to trigger the self-destruct at that point which would make the explosion newly scheduled rather than unscheduled.

SpaceX acquired a huge amount of data that would have otherwise been lost if the RSO was "quick on the trigger."

Example of a different rocket failure where the range safety officer let the rocket survive until it exceeded the safe trajectory box:

"Astra Rocket 3 LV0006 drifting launch & failure (NASASpaceFlight footage)" https://www.youtube.com/watch?v=HxVoBlgzZlQ

Also, N1 had many issues, non were really shown in this flight. So I don't know what you are referring to.

Maybe you are referring to the N1 failure where to many engine shut off, N1 used pure thrust vectoring for guidance and the board computer had a overly simple guidance computer where 1 engine getting shut down was automatically leading to a engine on the other side shutting down. This lead to a cascade where all engine shut down.

N1 also suffered from pipe failures because of vibration. Again not something experienced in this flight as far as we can see.

Can you be more concrete of what you are referring to?