Starship SN11 Launch Attempt Ends in Rapid Unscheduled Disassembly
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> At least the crater is in the right place!
> Looks like engine 2 had issues on ascent & didn’t reach operating chamber pressure during landing burn, but, in theory, it wasn’t needed.
> Something significant happened shortly after landing burn start. Should know what it was once we can examine the bits later today.
Q: After cleanup, will you roll out SN15? Perhaps BN1 too?
> SN15 rolls to launch pad in a few days. It has hundreds of design improvements across structures, avionics/software & engine.
> Hopefully, one of those improvements covers this problem. If not, then retrofit will add a few more days.
For posterity, here's a link to the full 16 minute official SpaceX launch stream (obviously quickly wrapped up after the failure): https://youtu.be/gjCSJIAKEPM?t=86
Yeah at this point everything before SN15 was already completely obsolete, which is why they didn't even bother finishing a few serials before it, and SpaceX only has so much actual physical room to store completed rockets there right now. They may have been getting into "launch it or scrap it" territory and just really wanted to move on, which would explain why this one seemed a touch rushed. Maybe they figured they might as well see if they could get some useful data out of it, and to some extent even launching under foggy and suboptimal conditions was itself a new thing to try. The advantage of a hardware rich cheap dev program, that entire launch probably cost a few million at most.
SN15 is going to be more interesting, the first really major revision towards "finished" status in a while. They're clearly confident they're making progress since they've begun pathfinding for the booster.
Unless the Raptor engines they flew were also old and obsolete.
>Raptor engines are still expensive.
They stated a while ago the cost of a Raptor was already under $1 million and that they're aiming for <$250k each with 2.0. That'd mean those three cost, at most and prototype status aside, a few million. That's just really not expensive in rocketry, or big machine early development in general. Even ignoring all other investment they can get, they're probably making at least $10-20m+ net income per commercial launch of the F9 at this point. So every single launch could cover multiple Starship tests. It's really wild how frugal it is compared to what everyone has become used to in rocketry, and in turn the kinds of things they can try.
Edit: just for context at the polar opposite end of the scale, "NASA will pay $146 million for each SLS rocket engine" (they need four per launch, and they're all thrown away each time).
https://arstechnica.com/science/2020/05/nasa-will-pay-a-stag...
Elon Musk has said "SpaceX needs to pass through a deep chasm of negative cash flow over the next year or so to make Starlink financially viable. Every new satellite constellation in history has gone bankrupt. We hope to be the first that does not." (https://twitter.com/elonmusk/status/1359024384200101888?)lan...
At this point their R&D spending on Starship and Starlink means they're running off constantly raising capital from investors (same as many other startups). When Starlink is generating decent income they're going to be an extremely profitable company, but they're not there yet.
For those unfamiliar, here's a great overview of the Artemis HLS landing systems: https://youtu.be/WSg5UfFM7NY?t=47
A private company developing a Super Heavy Lift Mars/Moon rocket and streaming the monthly tests online. Very exciting times.
In fact, SpaceX would not exist without the governmental effort to create a private space industry which has pumped a LOT of money into SpaceX and competitors.
But the conversation is always around investors and not about those who actually made this possible, the American tax payer.
It's true that SpaceX was helped by NASA after they got their first successful launches of Falcon-1, that help was important and allowed skipping Falcon-5. However that's the regular way American taxpayers - represented by those government departments - operate: they grow markets of new products and services, and then both benefit from new offerings and receive tax from them, while public has more chances for personal enrichment.
In some sense, yes, it's American taxpayer who makes all that - including favorable legal environment - possible; on the other hand, investors are the standard way, the means how that is done. It's odd to see taxpayers and investors as completely opposing entities.
That said, SpaceX has made a habit of defying my expectations in the past.
The PT-6 is an example of this; in North America, it stands alone, undisputed king of it's class. What's ridiculous is that turbine engines are simple. More simple than piston engines, and everyone and their dog can build a piston engine.
They were, SN15+ will use pre-production Raptors instead of prototype ones. A few of the newer engines have already been spotted, they are much cleaner in design and their mounts are rotated compared to the earlier engines (making them incompatible with the rockets that have flown so far)
why not talk about the failure's possible causes for 3 hours? would be more interesting than not
The last images those cameras broadcast were of large pieces of debris falling out of the foggy sky, smashing into the ground around the camera, splashing up dirt, and then everything went dead. I feel bad for the guy, but the look on his face as he realizes what's happening is priceless. I donated $5 just for that.
Edit: Here's the moment - https://www.youtube.com/watch?v=myVvmb2dF9U&t=2h19m32s
If you want to watch third-party livestreams, I usually recommend the NASASpaceFlight streams [1] that have more fact-based narration. They also had debris hitting their camera, but it seems to have survived.
[1] https://www.youtube.com/channel/UCSUu1lih2RifWkKtDOJdsBA/vid...
In this video you can hear engines start then an immediate explosion https://mobile.twitter.com/TheFavoritist/status/137689513012...
Possible the burn started late right above the ground. But I reckon we would have seen a larger explosion on the cameras in that case.
The next big milestones are SN15 launch (major upgrades in that version onward) and the booster launch (hasn't been tried yet).
They are hoping to get the 2 stage to orbit this summer, so probably after at least 4 more tests.
That link is the best coverage of the next flights SN15, SN16, SN17 and BN1, BN2, BN3. The aspirational schedule has been confirmed by Elon
https://twitter.com/_brendan_lewis/status/137556748395276288...
I also noticed (and this could be entirely unrelated) that during the ascent one of the engines was burning a bit richer than the rest. Notice that the flame is quite a bit more orange during ascent: https://youtu.be/bDL-ZMRHYrE?t=8208 It becomes a bit more noticeable once they get higher in the atmosphere and the cones expand.
Well sure, but people still have eyes. You would want to visually see what's happening with your rocket test wouldn't you? It just makes no sense why they didn't scrub for a few hours. Especially given the abundance of caution SpaceX has always shown with that.
Not really? You'd just see it explode, not much information to be gained from that.
> It just makes no sense why they didn't scrub for a few hours for it to clear out
Winds (which are much more dangerous for a rocket than fog) were forecasted to pick up later in the day.
SpaceX treats customer payloads with an abundance of caution, internal tests... not so much.
Even with all that fog.
So what is actually happening, these Starships are burning the methane into CO2, which is a far less potent greenhouse gas than is methane.
The other factor is that I don't think SpaceX see software as a differentiator. They have talented software engineers, sure, but a lot will be a very different type of software engineering to the typical FAANG sort, lots more real-time and embedded software. I believe their main piece of non-real-time/embedded software is their inventory/work management application which is all on the Microsoft stack. My gut feeling, could be wrong, is that your average .NET dev makes less than your average dev at a FAANG company. The market may just not need the higher salaries.
I know a number of people working in engineering in SpaceX (as in, designing the rockets or modules), and most of them are making between 50k and 90k, despite having PhDs or years of experience in aerospace engineering. To put the salary in perspective, a few of these people took a pay cut when they left JPL to work for SpaceX.
They work at SpaceX because they find the work exciting and rewarding, but if you're in it for the money you'll have to work at one of their competitors.
1. start the most advanced rocket engines (full-flow staged combustion cycle engines [1])
2. ascend to 10km gradually shutting down (and throttling) engines to keep relatively constant speed while methane and oxygen are depleting
3. switch from vertical ascent to horizontal descent flight profile, and from 10km "fall" (or rather fall/glide) into the 30 meters target of the landing pad
4. reach soft landing (almost accomplished by the SN10)
BTW Roughly only the first two of those items are in the "normal" checklist of any other rocket company for an orbital rocket.
SpaceX is following somewhat Soviet rocket development approach with many testing, which is not a bad thing by itself. It is just different to what we are used with NASA/ULA/et al. SpaceX is also very open with their testing, you can literally see the rocket from 50 meters away, and its launch (from 8km) freely. We obviously have an observational bias here, while not knowing how many failures others have.
[1] https://en.wikipedia.org/wiki/Staged_combustion_cycle#Full-f...
Well, not. During SN9 flight, one engine could not be re-lit, so SN9 crash-landed. During SN10 flight, the two engines that were needed for landing were lit, but there was an imbalance in the fuel mixture, one engine burned noticeable more yellow than the other, and now this. You'd think they'd analyze telemetry data from flights and on-ground testing and improve their design, but visibly they don't.
And they are on notice already from the FAA for routinely blowing stuff up near a populated area.
They're having some trouble restarting them on landing, because getting the fuel to flow properly with that dramatic flip in the air is a bit of a challenge, which nobody else has ever attempted.
The lessons from SN9 and SN10 are probably incorporated SN20 or even later version. (Or corresponding versions of Raptor engines.)
SN15 (the next launch) has a tweaked design of engines, but once again they are going to have multiple launches with these specific engines even if data from the first launch suggests some improvements. In fact, they had originally planned to do even more testing with this design (SN12,SN13,SN14 which had a bunch of work already done).
I wonder if while making Raptors some interesting techniques were created. For F-1 the result was so good the production engines routinely dampened instabilities, so Saturn-V didn't have this kind of problem in flight. Raptors seem to be less developed - of course, they have much higher chamber pressure and efficiency...
I can't tell if you're trolling, or if you're serious? SpaceX does an incredible job of instrumenting their rockets. They do plenty of "on ground testing" of Raptor, but some things can only be tested during flight.
FAA gives launch approval knowing full well what can, and does, go wrong. It’s FAA’s job to deny on the slightest justification of risk notice.
Unlike the Soviet Union, SpaceX can afford to fund their version of the "N1" moon rocket: at around $1 million per Raptor engine (and 3 Raptors per Starship hop test) the R&D program is still relatively affordable, even with the failures.
This philosophy is in stark contrast to the SLS (Space Launch System) which after decades of development has only just done a static fire. Also SpaceX's philosophy around the Starship test program is focused on building a factory that can manufacture thousands of Starships vehicles a year.
But I agree on the spectrum between "analysis paralysis" and "reckless" SpaceX is arguably a bit too far towards reckless at the moment.
I hope apparently wasteful R&D program yields better results soon. They need to start testing rapid reuse for Starship to be able to meet its cost goals.