Scott Manley with his take and interesting footage;
https://www.youtube.com/watch?v=CF9mdMI1qxM

flyingturtle wrote:

Just a few questions...

- has the Starship size been finalized? Until SN8, there has been a progression of larger test vehicles, starting with Hoppy. AFAIK the current Starships have small tanks, ones that only have to supply atmospheric Raptors for 4-ish minutes of powered flight.
- has there been any indication of when the Booster will be first flown, e.g. for hover tests?

Except for Hopper, Starship prototype tank sections have all been full size. They just added empty noses after SN6.
The first booster could be ready in a couple of months, but having the stand and ground systems ready will probably be longer. They'll only have four engines to start. They're actually much simpler than Starships. You should see the booster stand progressing shortly.

From this angle. you can tell that the trigger for the explosion was probably the lack of water being pumped on the bottom. less than 10 seconds after the water stops, the rocket explodes. The water was probably helping to disperse the Methane that was leaking.

You can also tell that the rocket was not on it's legs, and if you go back a bit in the video, the angle it sits at is indicative that the single rocket was probably battling the sea breeze to keep it verticle.


https://youtu.be/dkXUS321oZ4?t=993

casinterest wrote:

From this angle. you can tell that the trigger for the explosion was probably the lack of water being pumped on the bottom. less than 10 seconds after the water stops, the rocket explodes. The water was probably helping to disperse the Methane that was leaking.

I don't agree. Water does not disperse a gas very well, and methane isn't that water-soluble either. Water only cools incendiary sources, like hot engine parts.

It's a tiny bit like the burning Notre Dame cathedral - walls and roofs that protect the hot stuff from the nasty water.

A fan wouldn't have helped either, because of the skirt.

flyingturtle wrote:

casinterest wrote:

From this angle. you can tell that the trigger for the explosion was probably the lack of water being pumped on the bottom. less than 10 seconds after the water stops, the rocket explodes. The water was probably helping to disperse the Methane that was leaking.

I don't agree. Water does not disperse a gas very well, and methane isn't that water-soluble either. Water only cools incendiary sources, like hot engine parts.

It's a tiny bit like the burning Notre Dame cathedral - walls and roofs that protect the hot stuff from the nasty water.

A fan wouldn't have helped either, because of the skirt.

The water was hitting with pressure, heat and dispersion were forming and water vapor, all allowing for more mixing and containment of the methane and Lox/ . The area right above where the explosion started was where I think the LOX was being emitted. The water was probably distilling all of it. When it stopped, the pooling happened and within 10 seconds the explosion occurred. Maybe due to the LOX rich environment, and the fire that was probably still burning under the skirt.

It appears they are zeroing in on the cause of the explosion of SN10; the rocket suffered a hard landing, with thrust being low despite the engine being commanded high, per a tweet from Elon:

https://twitter.com/elonmusk/status/1368016384458858500

Elon is suggesting that they will instead have a minimum of two engines all the way to the ground & restart the third engine if engine 1 or 2 have issues.

Fun fact....The storage tank for firefighting water is Hopper.

ThePointblank wrote:

It appears they are zeroing in on the cause of the explosion of SN10; the rocket suffered a hard landing, with thrust being low despite the engine being commanded high, per a tweet from Elon:

https://twitter.com/elonmusk/status/1368016384458858500

Elon is suggesting that they will instead have a minimum of two engines all the way to the ground & restart the third engine if engine 1 or 2 have issues.

These spark relights while falling seem to have been pretty eventful. It also seems like the raptors really struggle with throttle control, particularly at the low end.

ThePointblank wrote:

It appears they are zeroing in on the cause of the explosion of SN10; the rocket suffered a hard landing, with thrust being low despite the engine being commanded high, per a tweet from Elon...

Not all of the landing struts locking on deployment (you can clearly see about half of them just swaying in the slow-motion) didn't help, either.

Stitch wrote:

ThePointblank wrote:

It appears they are zeroing in on the cause of the explosion of SN10; the rocket suffered a hard landing, with thrust being low despite the engine being commanded high, per a tweet from Elon...

Not all of the landing struts locking on deployment (you can clearly see about half of them just swaying in the slow-motion) didn't help, either.

It wouldn't have mattered. Touchdown was way too hard for the legs.
They get a pained look if you ask them about the leg deployment and won't talk about it.
SN11 will be the last of the old types to fly and they hope to go higher after that. It should move to the pad in a few hours.

What are/will be the planned changes from "old type" to "new type"?

Tugg

SN11 is on it's way to the pad. It almost ran over a snail, but the snail managed to outrun it.

Nomadd wrote:

SN11 is on it's way to the pad. It almost ran over a snail, but the snail managed to outrun it.

I was watching that when I posted! Sloooooww, very slow. But it's moving!!!

Tugg

Tugger wrote:

What are/will be the planned changes from "old type" to "new type"?

Tugg

Don't really know. The end of the nose is still lopped off for some reason. They're using 3mm steel instead of 4mm in places and real legs are hoped for.

More info on what SpaceX has planned for their south Texas facility:

The major hardware that exists or will be built includes:

Two orbital launch pads, one of which is already under constriction
Two suborbital launch pads, one of which already exists
Two landing pads, one of which already exists
Two structural test stands for Starship and the Super Heavy booster
A large "tank farm" to provide ground support equipment for orbital flights
A permanent position for the totemic "Starhopper" vehicle at the site's entrance

What is striking about this architectural drawing is its compact nature, largely because SpaceX has limited land to work with at the facility and must include stormwater ponds to mitigate against flooding. All of these facilities will be concentrated within a couple dozen acres, which is in stark contrast to more expansive launch sites in Florida at Kennedy Space Center and Cape Canaveral Space Force Station.

https://arstechnica.com/science/2021/03 ... uth-texas/

Full proposed plans: https://www.swg.usace.army.mil/Portals/ ... 300381.pdf

Official public notice:
https://www.swg.usace.army.mil/Media/Pu ... ron-count/

Tugg

Doesn't the proximity of the launch and landing facilities risk damage to the neighbouring pads, and to vehicles waiting for launch there, in case of an explosion?

If that's not an issue, why did NASA build their stuff so far apart at KSC in the first place?

Technically yes, but they use flight profiles that sort of "funnel" the debris away from sensitive things. The SN9 crash was a good example of this. The angles that the live streams captured made it look like SN10 and SN7.2 were in peril, but the overhead shot from RGV Aerial Photography shows the blast actually blew the debris away from SN10 and SN7.2, not at them.

As to why NASA is so spread out at KSC, I'm guessing its because when the land was allocated, we really sucked at keeping rockets unexploded. Test fires would go wrong and take out the whole pad, so they built a ton of pads really far apart.
Also, "rapid-reuse" was not a consideration when NASA laid out KSC.

mxaxai wrote:

Doesn't the proximity of the launch and landing facilities risk damage to the neighbouring pads, and to vehicles waiting for launch there, in case of an explosion?

If that's not an issue, why did NASA build their stuff so far apart at KSC in the first place?

Complex 39 was designed for LOX/Hydrogen boosters. Much more energetic than LOX/RP1 combo SpaceX is using.

zanl188 wrote:

mxaxai wrote:

Doesn't the proximity of the launch and landing facilities risk damage to the neighbouring pads, and to vehicles waiting for launch there, in case of an explosion?

If that's not an issue, why did NASA build their stuff so far apart at KSC in the first place?

Complex 39 was designed for LOX/Hydrogen boosters. Much more energetic than LOX/RP1 combo SpaceX is using.

They don't use kerosene in Boca Chica. They use Methane. Over a thousand tons of it eventually. If that mixed just right with the air/O2 from the tanks and detonated, I doubt if my Home Depot windows would live to tell about it.

I got this yesterday and thought it was a good SpaceX/ULA way of doing things contrast. They set SN11 on pedestals for a few minutes to do a quick deployment test on the legs before lifting it to the launch stand. Method is a bigass crane and a bunch of people who didn't seem busy when the boss looked around. If anything was wrong, it probably would have been figured out and fixed in two days. I think Rutan would love this place.
It also gives a good sense of scale for people who don't realize how big this beast really is.

I love the blue collar nature of that picture.

A friend of mine has always been annoyed at the perception people have of engineers. He terms himself a "Bluecollar Engineer" to make it clear to people that there is hard dirty work involved. Good engineering is not just "design on a computer" (though there are many engineers like that). As he puts it "a real engineer will get their hands dirty, see what and how their design/enginneering does in the real world" and that is the only way to "learn to become a real engineer not just a computer jockey".

Tugg

Tugger wrote:

I love the blue collar nature of that picture.

A friend of mine has always been annoyed at the perception people have of engineers. He terms himself a "Bluecollar Engineer" to make it clear to people that there is hard dirty work involved. Good engineering is not just "design on a computer" (though there are many engineers like that). As he puts it "a real engineer will get their hands dirty, see what and how their design/enginneering does in the real world" and that is the only way to "learn to become a real engineer not just a computer jockey".

Tugg

My favorite thing about that photo as well. These folks look like they were on a job site building houses yesterday, and today they’re building rockets.

It’s a refreshing angle on spacecraft. No sterile white rooms, and the accessibility to the public is amazing. Go to KSC and you’ll be lucky to come within a mile of any vehicle. Meanwhile at Boca Chica you can practically go sit on the side of the road as they roll out a prototype.

Elon is saying SN10's engine thrust was low (probably) due "to partial helium ingestion from fuel header tank. Impact of 10m/s crushed legs & part of skirt. Multiple fixes in work for SN11."

https://twitter.com/elonmusk/status/1369379914139451406

Another tweet where a discussion about the use of helium in the header tank notes the reason why:

https://twitter.com/elonmusk/status/1369382210894237705

Fair point. If autogenous pressurization had been used, CH4 bubbles would most likely have reverted to liquid.

Helium in header was used to prevent ullage collapse from slosh, which happened in prior flight. My fault for approving. Sounded good at the time.

And of course, further discussions about how to land Starship, including a random though about Starship being caught by the launch tower, or by having it land on a big net or a bouncy castle:

https://twitter.com/elonmusk/status/1369458403248988160

Might just catch the ship with the launch tower, same as booster

https://twitter.com/elonmusk/status/1369489056350883840

Yeah, we talked about that internally. Could just have it land on a big net or bouncy castle. Lacks dignity, but would work. But, optimized landing propellant is only ~5% of dry mass, so it’s not a gamechanger.

[quote="ThePointblank"][/quote]

"Lacks dignity"

Yes, I'm absolutely in love in how Elon pushes the big rokkit forward and upward!

It's interesting to watch a company engage in hardware-rich development, and being able and willing to loose hardware during development and testing.

They are acting with a surprising amount of speed and agility based upon their responses to the technical data that's coming back to them from each test, and are willing to air much of their decision making processes in public.

Tugger wrote:

A friend of mine has always been annoyed at the perception people have of engineers. He terms himself a "Bluecollar Engineer" to make it clear to people that there is hard dirty work involved. Good engineering is not just "design on a computer" (though there are many engineers like that). As he puts it "a real engineer will get their hands dirty, see what and how their design/enginneering does in the real world" and that is the only way to "learn to become a real engineer not just a computer jockey".

Yep. I'm an engineer and have a lot of "hands-dirty" experience, mostly outside of work but on similar projects (like building my airplane, working on the car, building my workshop, etc.). Too many engineers never get their hands on hardware and barely know which end of a screwdriver to hold.

I really wish my employer would let me spend some time (a couple months preferably) on the floor working alongside some of the maintenance crews--there's a lot of stuff I could learn from them that would really help in my job--but between FAA repair station requirements and management thinking we're "too expensive" to be spending time doing that, they won't let me.

I did at least get to spend one day a week in a machine shop for a while, and got to shadow our NDT techs for a week. Learned a lot from both of those experiences, but it practically took an act of Congress to make those happen.

I had the misfortune to be in companies where the worst insult they had was "Scarier than an engineer with a screwdriver".

Nomadd wrote:

I had the misfortune to be in companies where the worst insult they had was "Scarier than an engineer with a screwdriver".

good hands on experience is a boon.
But do not underestimate theoretical/analytical understanding.

I am a natural with tools.
But without the theoretical/analytical background acquired through a formal scientific education
I would be nothing more than an accessorizing trades person.

a formal education will give you wider scope of learning than
going on your own and aquiring the information bits that directly come up as questions.

( one of the enlightening things in my education was joining all that disjunct theoretical stuff
from the different courses into one homogenous toolset for solving problems.
Not just electrrical engineering ( what I had signed up for)

.... and SpaceX launches, and lands, a Falcon 9 for a record ninth time. We live in exciting times.....

zanl188 wrote:

.... and SpaceX launches, and lands, a Falcon 9 for a record ninth time. We live in exciting times.....

And seemingly, SN11 is about to launch... *checks notes*... only 13 days after SN10 exploded.

A third of that 9th booster's missions have been since December.
I think we are getting a better picture of how resilient they are now.

GDB wrote:

A third of that 9th booster's missions have been since December.
I think we are getting a better picture of how resilient they are now.

That booster just passed the Skylab Saturn 5 for payload launched and has now lifted more than any booster in history. It just took a few tries.

Nomadd wrote:

GDB wrote:

A third of that 9th booster's missions have been since December.
I think we are getting a better picture of how resilient they are now.

That booster just passed the Skylab Saturn 5 for payload launched and has now lifted more than any booster in history. It just took a few tries.

I’m actually not sure which aspect of that impresses me more.

Saturn V was an incredible vehicle. But so too is the Falcon 9

SN 10 flight

https://youtu.be/gA6ppby3JC8

SN10 with a cheap, crooked security camera.
Also, SN11 going to the pad if you're in a hurry.
Like Opportunity's solar panel, the 40 foot high camera is almost inaccessible and has to wait for weather to clean the lens. But it's been going for two years without human intervention.
I always kind of liked the delayed audio making the camera shake 7 seconds after the fact.
https://youtu.be/7Zxno0jo2x0
https://youtu.be/Fqj_cWTJf4I

This is one bigass booster. 9 meters wide and 70 meters tall. It just needs a 50 meter tall Starship on top to complete the picture.

*This camera is connected to the computer through a piece of Cat 6 scavenged from the wreckage of SN 10.*

Nomadd wrote:

This is one bigass booster. 9 meters wide and 70 meters tall. It just needs a 50 meter tall Starship on top to complete the picture.

There's a few things I don't get about their stacking approach... Are they really using Tankzilla (through the high bay roof) to lift and stack the booster sections? I notice they were using smaller cranes to stack Starships as well.
You'd think the main purpose of having built a large hangar for stacking would be the benefit of having a gantry crane in the ceiling, along with a way to laterally stabilize the sections so they wouldn't dangle about the way that booster piece did?

*edit* Nevermind, just watched yesterday's NSF video showing the gantry crane being delivered.

Also, I didn't realize the High bay was only tall enough for the booster. What's their plan for final stacking? I can't see anything tall enough to do that anywhere on site...

*This camera is connected to the computer through a piece of Cat 6 scavenged from the wreckage of SN 10.*

lol.

Francoflier wrote:

There's a few things I don't get about their stacking approach... Are they really using Tankzilla (through the high bay roof) to lift and stack the booster sections? I notice they were using smaller cranes to stack Starships as well.
You'd think the main purpose of having built a large hangar for stacking would be the benefit of having a gantry crane in the ceiling, along with a way to laterally stabilize the sections so they wouldn't dangle about the way that booster piece did?
*edit* Nevermind, just watched yesterday's NSF video showing the gantry crane being delivered.
Also, I didn't realize the High bay was only tall enough for the booster. What's their plan for final stacking? I can't see anything tall enough to do that anywhere on site...

They never even considered trying to transport the whole stack. The Starship will be lifted onto the booster at the pad with a 150 meter or so tower/crane they're working on now.

That makes sense. Thanks.

Good to know you guys are getting a skyscraper down there.

SN11 just had a static fire, if the data is smooth we'll most likely see it launch later
Very hazy weather though...

Very unusual launch of sn11. Too foggy to really see much, and now it appears the vehicle broke apart midair while doing the landing flip.

Really looking forward to what spacex has to say about this one. After coming so close last time, it's too bad

FGITD wrote:

Very unusual launch of sn11. Too foggy to really see much, and now it appears the vehicle broke apart midair while doing the landing flip.

Really looking forward to what spacex has to say about this one. After coming so close last time, it's too bad

Elon is saying some sort of issue with engine 2 during ascent, and on the landing burn:

https://twitter.com/elonmusk/status/137 ... 17090?s=19

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.

Again, there was a fire near the base of one of the engines since early in the launch, I'd say from a methane leak.
The telemetry, at least the video part of it, was crap throughout.
And again, it seemed there was a problem with Raptor ignition for the landing burn and another RUD, eerily shrouded in fog, and seemingly more violent than even the previous ones.

One step forward, 2 steps back...

It may be time for SpaceX to take a break from testing and take a closer look at their design, here. I have the feeling the Raptor is not quite there yet, or at least the part where it re-ignites from horizontal freefall. That violent 90 degrees rotation doesn't seem to play nice with fuel and/or oxidizer flow,

I wonder whether the FAA is starting to lose patience. How many giant rockets need to crash out of control and explode near a populated town before they start raising an eyebrow?

The next bird - SN15 - has significant upgrades from SN8-SN11 so I expect them to want to launch SN15 and see how it performs.

Francoflier wrote:

Again, there was a fire near the base of one of the engines since early in the launch, I'd say from a methane leak.
The telemetry, at least the video part of it, was crap throughout.
And again, it seemed there was a problem with Raptor ignition for the landing burn and another RUD, eerily shrouded in fog, and seemingly more violent than even the previous ones.

One step forward, 2 steps back...

It may be time for SpaceX to take a break from testing and take a closer look at their design, here. I have the feeling the Raptor is not quite there yet, or at least the part where it re-ignites from horizontal freefall. That violent 90 degrees rotation doesn't seem to play nice with fuel and/or oxidizer flow,

I wonder whether the FAA is starting to lose patience. How many giant rockets need to crash out of control and explode near a populated town before they start raising an eyebrow?

You don’t really know what the telemetry was, just the video feed they put on YouTube. That’s the toughest data stream to maintain (moving picture), and they did pretty well with it, as well as the camera outside, and inside the tanks.

Finally, the RUD did happen, yes, but it’s also proven again the ship can fly, belly flop to terminal velocity, and then they’ve had trouble yes with the raptors. Significant changes in engineering are reported on the reworked raptor for SN15, as well as ‘over a hundred’ changes for the ship itself. I think I read this am that Elon said SN15 to the pad in ‘a few days.’ This rapid iterative prototype/testing process is fun to watch, and I expect they will have a fresh analysis of what went wrong with the relight this time. Elon also said they are expecting to add ‘several thousand’ employees at the Boca Chica site over the next couple of years.

It did explode/terminate; right over the launch pad. I get it, some hate this company for threatening the entrenched players, but let’s not be dramatic about this event threatening a population center.

This can't be cheap... reminds me of the question "what's the difference between a rat and a human?" Ans: after 2 failures a rat looks for a different approach where as a human will keep doing the same approach hoping for a better result.

They need to to stop hoping for a different conclusion and go back to the drawing board.

kanban wrote:

This can't be cheap... reminds me of the question "what's the difference between a rat and a human?" Ans: after 2 failures a rat looks for a different approach where as a human will keep doing the same approach hoping for a better result.

They need to to stop hoping for a different conclusion and go back to the drawing board.

And SpaceX and Elon Musk doesn't really care about the cost.

These were all prototypes, and even if they had managed to stick the landing, the most likely scenario for them was to be scrapped immediately and to move onto the next prototype. That's why SpaceX has already scrapped prototypes 12 to 14 during construction; so they could iterate the design for number 15.

I think from the viewpoint of Elon Musk, as long as nobody gets hurt and nobody else's property gets damaged, he doesn't care if a Starship prototype crashes during testing, as long as good data can be drawn from it.

texl1649 wrote:

I think I read this am that Elon said SN15 to the pad in ‘a few days.’ This rapid iterative prototype/testing process is fun to watch, and I expect they will have a fresh analysis of what went wrong with the relight this time.

I did not have any anticipation that SN11 would not prove much different than SN9 or SN10. They were too close together and SN11 was almost complete structurally when SN9 launched. So any plumbing, tubing or changes to the tank or pressurization/fuel feed would have been pretty much the same, just rearranging the deck chairs to try and make that design work.
SN15 is suppose to be a bit of a design change we just do not know if the changes are addressing every issue present to this point.

The Raptors are quite a feat of engineering and are making serious amounts of thrust above and beyond their original design criteria.
330bar chamber pressure is amazing however if you count the number of replacement Raptors from static fire that have failed on 9,10 and 11 just sitting on the pad you are looking at 50% failure not counting in flight failures of unknown origin has exposed serious reliability issues.
The reliability of the Raptor is going to have to come up massively before it would even be considered for a human flight.

Okie

casinterest wrote:

aumaverick wrote:

Why did SN9's body (1/4 up from base) and nose cone appear to be frosted during the flight? Was there a leak somewhere causing the steel to freeze?

That is the frozen fuel condensation freezing on the outside. You can see it on the pad as well. There isn't much insulation on starship right now.



https://space.stackexchange.com/questio ... he-vehicle

All the rockets form ice on the pads with the low temperature liquid fuels.

Why is the Lox header tank so far from the Lox tank? Are they pumping fuel so high up?

texl1649 wrote:

Francoflier wrote:

Again, there was a fire near the base of one of the engines since early in the launch, I'd say from a methane leak.
The telemetry, at least the video part of it, was crap throughout.
And again, it seemed there was a problem with Raptor ignition for the landing burn and another RUD, eerily shrouded in fog, and seemingly more violent than even the previous ones.

One step forward, 2 steps back...

It may be time for SpaceX to take a break from testing and take a closer look at their design, here. I have the feeling the Raptor is not quite there yet, or at least the part where it re-ignites from horizontal freefall. That violent 90 degrees rotation doesn't seem to play nice with fuel and/or oxidizer flow,

I wonder whether the FAA is starting to lose patience. How many giant rockets need to crash out of control and explode near a populated town before they start raising an eyebrow?

You don’t really know what the telemetry was, just the video feed they put on YouTube. That’s the toughest data stream to maintain (moving picture), and they did pretty well with it, as well as the camera outside, and inside the tanks.

Finally, the RUD did happen, yes, but it’s also proven again the ship can fly, belly flop to terminal velocity, and then they’ve had trouble yes with the raptors. Significant changes in engineering are reported on the reworked raptor for SN15, as well as ‘over a hundred’ changes for the ship itself. I think I read this am that Elon said SN15 to the pad in ‘a few days.’ This rapid iterative prototype/testing process is fun to watch, and I expect they will have a fresh analysis of what went wrong with the relight this time. Elon also said they are expecting to add ‘several thousand’ employees at the Boca Chica site over the next couple of years.

It did explode/terminate; right over the launch pad. I get it, some hate this company for threatening the entrenched players, but let’s not be dramatic about this event threatening a population center.

I'm sure the telemetry they got was good, but I found it surprising that they weren't able to maintain a decent video feed where it seemed to work fine on the previous flights. I don't know what kind of transmission method they use for telemetry. Maybe it's a tightly focused beam that was getting scattered by the thick fog, not sure. It just felt strange and was giving the vibe that things were not right from the get go.

As for proving Starship can go up and belly flop, it had done it before. It had done that beautifully 3 times already in fact. SN11 was another go at cracking the landing maneuver and nothing else. I very much doubt they needed any more data on the rest of the flight.

I do not hate SpaceX nor wish them misfortune, quite the opposite. The problem is that it's easy to get overly optimistic from their previous (amazing) achievements and forget that what they are trying to achieve with Starship is extremely ambitious and orders of magnitude harder than anything that's ever been done before.
Flipping and landing it is only a fraction of what it will have to achieve eventually. It still has to go to orbital velocity, suffer the extreme environmental conditions of space, survive re-entry, then successfully do the flip and land, and do it again multiple times without major refurbishment.
I do hope that Musk follows through with it all the way, but I think it is going to take more time and money than he believes.

And I do believe the FAA is going to put a damper on these flights until they are given much more solid evidence that this stainless steel shrapnel-fest is not going to be a regular occurrence going forward. Musk may be happy with launching and blowing up as many of these things as it takes to get it right, but I doubt the regulators will be, and the FAA is not exactly super happy with SpaceX to begin with... Especially now that politics are getting involved:

https://spacenews.com/congress-raises-c ... violation/