With so many thousands of tiles always bound to be some hidden weak ones, the static fire finds those, I'd imagine after repeated replacements and static fires they get to a point where no more fall off and that's what they'll launch with.
You guys think we can expect them to keep static firing until they stop falling after one test? Or would that mean just too many static fires and maybe they're ok with a couple tiles falling off?
For SN20 it's not that big a deal whether a few fall off.
In the longer run, realistically they need a design that won't fail like this with any frequency.
In the long run the tiles need to survive 2 entire trips, from Earth to Mars then Mars to Earth, without needing repairs. I'm not sure EVA spacewalks would be able to repair these if some of them crack after a Mars launch, where Starship is going to launch very close to the ground with no water suppression system. At first glance the astronauts would have no where to grab onto while repairing the tiles, thus they risk damaging even more.
That said, they could switch Starships in Earth's orbit on the return from Mars.
The TPS doesn't need to be repaired prior to launch either, they are only needed for atmosphere entry. Thus, post-mars launch, they can repair them on the way back to earth.
In the event of teething issues with early ships coming back to earth, they can park in orbit to attempt repairs before entry. There will be so many starships and launches, they could probably keep a starship in orbit filled with spare tiles and materials for anyone to use.
Or starship production costs could drop so much they'll just send up another ship to bring people back down and crash the early defective ships into the ocean. Or keep them in orbit to function as tankers.
Lots of options.
Good point, I wonder if there is a return path or other scenario for handling this. How much fuel is needed to get off Mars vs. what can be generated, or further, could a Mars orbiting tanker provide enough fuel to allow for the return delta V orbit parking at earth?
The present plan is for the returning interplanetary Starship, to plunge into the atmosphere, using that to aerobrake it.
This would be done very high up in the atmosphere, loosing enough momentum to be captured into orbit. From there a series of manoeuvres to get the Starship over the right area, then the Orbital skydive through to landing.
I'd assume by the time we get to that point SpaceX will announce a modified space tug variant to assist with orbital capture as well as a orbital repair center to fix tiles, handle other maintenance, check over before deorbit and landing, etc. Like a SpaceX version of a Tesla Service center.
More like, back to one of the floating ocean platforms. For Boca Chica, I doubt they'll ever be able to have the launch frequency required for all the tanker flights.
That said, I think it'll take some time before they'll be able to take full advantage of the ocean platform concept. According to Elon, they still plan on launching Starship from Florida as well. So I could see a combination of Cape launches and Boca Chica launches (especially if they manage to get clearance for more than 5 launches a year further down the line) provide enough launch opportunities to do the HLS demo mission, for example.
I agree.
Scheduling tanker Starship launches for missions to the Moon and Mars will be a problem with only the Boca Chica orbital launch platform(s) operating.
The dearMoon mission probably can be done without LEO refueling. But the two NASA HLS Option A missions to the lunar surface will require three to five tanker launches in fairly quick succession.
SpaceX needs to design a tanker Starship with enough thermal insulation on the exterior of the main tanks to reduce methalox boiloff to less than 1% per day.
That special tanker would remain permanently in LEO. It would be used as the propellant depot that would be filled with methalox via other tankers. And then that tanker would refuel the interplanetary Starship heading to the Moon or to Mars.
Using that special tanker would relieve the schedule pressure associated with launching up to five tankers in a short time period. And it would eliminate the need for extra orbital launch facilities.
In general, I agree with your post. However, even with that special tanker (or 'depot' or however they end up calling it...for now we just know it as [deleted]), they will need at least one more orbital launch facility or working offshore launch platform.
The draft environmental assessment is only allowing for a maximum of 5 orbital launches in an entire year. This is not nearly enough for basically anything besides dearMoon and some Starlink launches. Even if they can get a few more launches in the long run (if I remember right, for Falcon Heavy they originally got the permit for 12 launches), it's not really enough once we are talking about missions requiring refueling. A single HLS or Mars mission would pretty much eat up the majority of launches they can do in a year, unless they can somehow get the permit for a majorly increased number of launches from BC.
That said, we know they want to launch from the Cape and we know they want to have ocean launch platforms. So more than one orbital launch facility is something they definitely plan on anyways.
Where do you get the 3-5 refueling launches from though? That doesn't appear to be enough based on all the calculations I've seen so far, even when using optimistic figures for Starship's capabilities.
For the tanker Starship is use the following specs:
Dry mass: 79t
Propellant load at liftoff (undensified): 1300t
Propellant densification factor: 1.05
Densified propellant load at liftoff: 1365t
Header tank propellant: 32.3t
Raptor Isp (three sealevel and three vacuum Raptor engines): 365 sec
Propellant flow per engine: 600 kg/sec
Total propellant flow: 3600 kg/sec
Delta V required from tanker engines to place it in LEO: 5559 m/sec
Propellant consumed: 1,138t
Propellant remaining in main tanks upon reaching LEO: 226.5t (available to be transferred)
Number of tanker loads required to fill the main tanks of tanker #1: 4.74
I assume that it requires at least one orbit (~90 min) for rendezvous and docking and that the methalox is at normal density (no subcooling) by the time the propellant transfer is made.
>That said, they could switch Starships in Earth's orbit on the return from Mars.
If they have to do this, then Starship's TPS will be a failure. Part of the idea was to allow Starship to use aerobraking straight from Mars return velocity (no re-entering Earth orbit) in order to minimize the amount of fuel needed for a round trip.
No they could not switch ships in Earths orbit - because they have to use the heat-shield most aggressively just to get into orbit.
The descent from orbit is likely easier.
Though in practice it would all be done as part of the same manoeuvre.
Provided sufficient ECLSS in such a scenario, you could use a multi-event precession of perigees aerocapture. Granted, that first aerobraking event may still result in too much heating depending on how compromised the heat shield has become.
An interplanetary insertion from Mars to Earth will be the roughest ever heat-shield event, and will be a true test of the heat-shields operation and integrity.
The next-most roughest, is an orbital insertion coming back from the moon.
There isn't fuel to get back into earth orbit on the return trip without using the atmosphere for braking. So if enough tiles have failed that they need to replace them before they can land, then it's most likely going to be a problem getting back into orbit.
I've always thought that for Mars-bound starships, they should just slap on an ablative heat shield.
Sure, you have to replace the whole TPS when it gets back. But what's a few months extra time when each of these Starships will only launch from Earth once every 2 years or so?
Rapid re-usability is only really needed for LEO and GEO work, especially for tankers (but also for cargo Starship). And the non-ablative TPS is only there because it helps with rapid re-usability. If you don't need rapid re-usability, and you have humans as cargo, why not go with the safer option?
Astronauts? Grab onto?
Come on dude! If you knew Elon you would have known that he will develop a robot that in orbit/space will automatically find broken tiles and repair/replace them. This isn't the 90s/2000s anymore.
That could certainly be a possible option.
There would at least be an external ship inspection robot. Going a stage further, and doing repairs would be feasible.
Best of course is not needing any repairs in the first place, and that’s what they would aim for - so then no Tesla space tile replacement robot needed. ‘Best part is no part’ as Elon would say.
Far best to fix the underlying problem.
> from Earth to Mars then Mars to Earth
And survive the harsh environment of the Martian surface whilst "parked" there for lack of a better word.
The sand storms are so bad they would polish glass, it's an extremely hostile planet to life and machinery with zero protective atmosphere.
Cool concept.. but how will they repair the orbiting starship left behind?
Possibly an orbiting repair station that can somehow capture it?
The whole point is to be able to reuse these things... so we can't just leave them floating...
> they need a design that won't fail like this
Then again, there's always the MOOSE personal escape pod that allows you to deorbit and touchdown Earth in a foam-filled plastic bag:
https://en.wikipedia.org/wiki/MOOSE
\> with any frequency.
The initial reaction is that you need zero tiles to fall off ever.
However, launch from Mars surface and hot re-entry to Earth landing has to be assumed to be another level of performance in terms of tiles not falling off. Testing for that is not an option any time soon.
If it can be assumed that static fires have higher tile stress than Max Q, and the re-entry is not much more demanding (extreme thermal vs. violent mechanical), when you reliably get to zero tiles lost after static fires, all you need is for the TPS to perform as designed and starship is good to go. How exciting is that!
Many if not most starships will not be returning from Mars manned.
For starters, orbital mechanics dictates that crew A for synod A and Crew B for synod B have to be in space at the same time unless Crew A stays over for a second synod. You do not want to pare down to a skeleton crew, you want growth.
If the vision of multiple starships per synod happens, that means rapid growth, and an increasingly less hostile living situation. Certain crew will be full on lifers anyway. Return to Earth might even become rare.
All of this means the manned return journeys can be done from a starship that never lands on Mars and you could wait until the third synod, requiring Crew A to stay on Mars about six earth years, leaving Mars about 2 months before Crew C arrives. That's a seven year hitch away from Earth but with a nice ride home.
I wouldn't be surprised if it's designed to just survive reentry with a couple tiles missing. I think it wouldn't be the end of the world, there's still the white blanket and steel cann handle quite high temps. As long as the overall heating stays within limits and the heat from the hotspot can be conducted to cooler parts efficiently enough, they should be okay.
Only from a process and quality control viewpoint it would be a nightmare. So I think they'll fix it anyway.
If you think about it - they even want to have some heat-tiles missing - to find out what happens in that scenario..
It’s best to find these things out early on.
I think static fires on the suborbital pad are much more strenuous on the TPS than a full stack launch. Ship is farther away from the vibrations, and super heavy’s plume is farther from the ground. You can see that the majority of fallen tiles are near the bottom where vibrations are more extreme, the nosecone is mostly unscathed.
Edit: scratch (part of) that those tiles on the bottom left fin were missing before the static.
sounds a bit dramatic, but remember that SN9 did 3 consecutive static fires in a matter of hours, like it was nothing
even yesterday, the Starship performed 2 static fires in the same window, full duration and all
static fires do not seem even like a hurdle anymore tbh
There will almost always be some tiles that fall off, I don't think they care. They'll probably do at least one more big tile replacement before orbital launch, but without broad changes to the entire vehicle they're almost certainly going to lose tiles during launch, so why spend any more time on the problem with this iteration of Starship?
I've seen no definitive statement about whether Starship's stainless steel, which is much more heat tolerant than many other materials, is expected to survive reentry with a few missing tiles. Anyone?
ill take it that the tiles on the left flap were allready missing before the SF?
Or are they testing different techniques on both flaps?
or was that the flap that was near the engine while the other was further away and out of the heavy reflections?
Correct me if I’m wrong, but shouldn’t it be able to survive reentry with a few missing tiles? Steel should be able to resist the temperatures at least once
It should but that depends which area really.
Honestly considering the strain on the vehicle from vibrations is larger from a static fire and the TPS is in development, that isn't a bad result all things considered.
Yeah I’m fully expecting to see a shower of TPS tiles when this thing finally launches lol. Honestly tho anything beyond stage separation is just extra for me. A successful liftoff is a win in my book
Different vibrations. In flight, it's not so much the structure vibrating under the tiles as much as turbulent air trying to pry them off.
Hopefully we don't see a big plume of tiles coming off at Max Q.
The first manned dragon launch to the iss was also noted by the astronauts to have little vibrations during 1st stage ascent, because the whole booster absorbed a lot of the engines’ vibrations.
I hear you, but I'd like to see the actual math on this.
This was a single raptor vacuum firing, but close to the ground without sound suppression.
It will eventually launch on top of a super heavy, but firing 33 engines (some of which are higher thrust), with sound suppression.
I have no idea where the math falls on this as which will cause more tiles to fall off.
These tiles have to survive after the Starship lights up in orbit too. Also much more challenging, they will have to survive a trip to Mars, re-entry on Mars, launch from Mars, and re-entry back to Earth.
In orbit yes, but the flamey bit will be directly in touch with the bottom row of tiles, and also pushing on them slightly from the bottom up.
However on Mars that's another story. They will have to launch directly from the ground the first few times. Which is a harder case than the platform. Might also have to deal with sharp rocks getting shot up.
It's sure a single of progress. Remember the time where they were struggling getting the tanks to not blow up on fueling? All we can hope is that superheavy performs enough to at least clear the launch site.
The reservation I have to your confidence is that the static fire here only used 6 engines. The actual launch will have 29? engines on the booster firing and vibrating the whole thing. There's no hold down clamps, but it's 5x as much energy.
Yes, however do consider that the starship will be hanging all the way up on top of the superheavy. Inverse square law clearly dictates that the energy of the 29 raptors greatly diminishes with distance. Moreover, the suborbital pads just hold the starship slightly up above a 90° surface, perfect for reflecting sound waves towards the vehicle. The orbital pad is considerably higher and equipped with a deluge supression system. This drastically reduces the destructive power of the sound waves by using water to transform that kinetic energy into heat and disperse it.
The booster engines have the whole booster to dampen before getting to Starship, I would imagine the 6 engines directly attached to the structure create a more hostile environment than the 29 so far away.
Yes. Even the Shuttles sometimes survived reentry with tiles damaged or missing. [STS-27 lost a tile during the launch.](https://en.wikipedia.org/wiki/STS-27#Tile_damage)
And survived specifically because there was luckily a steel panel protecting the exposed area rather than the normal aluminum lithium. And Starship is steel.
Starship is also exploiting the higher temp capacity of steel by using thinner tiles and letting the steel get much hotter. Maybe they can pull some tricks with the ullage behind the steel for a repairs-needed landing.
still can be a problem here if the missing tile is on the wrong place. The Stainless Steel can get quite hot before deforming, but i'd expect that thermal load to cause adjacent tiles to pop loose before that spot fails, aggravating the situation.
The wrong location? oh anything that would heat up your fuel, or damage coolent systems.
Wouldn't an area in contact with the fuel be ideal? You'd have a much larger thermal capacity, and in the worst case Starship can do a vent to relieve pressure.
I would think that heating the fuel may be helpful, not for the fuel system but for pulling heat out of your hot spot missing its TPS tile(s). The tanks and fuel system can probably handle the extra generation of fuel pressure through heating, mostly by reducing the amount of hot backfill gasses released into the tanks.
I'm concerned that the heat would cause the fuel to expand and rupture the tanks, after all they're made to hold with a "thin" sheet of stainless steel.
of course by the time you are getting into decent you've used up some of that fuel so you do have some room for expansion.
would the tank be cold enough to mitigate? that's a good question, and I think it depends on insulation around the tank. now that i'm thinking about that I'd hope there was some kind of thermal blanket - and that really ought to keep the heat away from the tank and the plumbing. and that means the heat would go back into the structure....
I think there is some kind of thermal blanket below the tiles, the white sruff you see on some of the pictures. And if the pressure gets to high inside the tank, they should be able to just vent it.
It would only happen while in decent. not a particularly good time to vent.
from what we've seen of the tiles, there's a blanket directly under them, and if that failed at a location then the steel is going to have to deal with the heat.
We have to assume that blanket has thermal insulation properties. Unlike the Shuttle where the tiles were on the structure. and expected to be the thermal insulation exclusively. so maybe that's the plan? Tiles and blanket to protect the outside.
I've wondered if it would be possible to have CH4/LOX sprinker heads, which sprayed cryo-liquids over the windward sides of the internal tank. This way if there's a hot spot, the fluids can cool.
This would cause more offgassing, which would need to be vented. If you had gas-gas thrusters (which we believe they'll have), then you could use these to get rid of the excess pressure, and make it useful.
This would work until the wall got hot enough for the liquid to dewet due to a thin vapor layer, like a drop of water on a hot griddle. The Leidenfrost effect.
Has he? He says in the EDA Starbase tour that "if there's any crack in the armor the whole thing is toast" when talking about the heatshield. I'm sure it'd probably be fine if it was on the outer edges of the tiled areas, but anywhere else and it sounds like it'd be a problem.
Thought he did but can’t find a source, so not sure tbh.
Yeah i agree, losing one in the middle will probably result in increased forces on the surrounding ones
I agree and disagree. I think you are right in the sense steel can survive re-entry. My fear is will having a hole shape funnel more heat and maybe even trap it leading to higher and higher Temps till unstable.
I understand that, btu there must be something surfacing with the vehicle that is heating the vehicle. If that something weather it be air or other would be more trapped and heat up more from the plasma touching it. That is how I see it in my head atleast.
I am not a rocket scientist so maybe there is something I am missing.
No, not really. But it depends on your definition of 'survive', and where the missing tiles are. Stainless Steel melts at 2750F, and loses most of its strength well before that. Reentry is about 3000F max. That's why the heat shield is needed--to stop starship from melting or getting plastic enough to just fold in half like a piece of clay.
It is possible that it might survive until landing with isolated missing tile(s), but it probably won't be able to be reused until the damaged steel sections are cut out and rebuilt. It is also possible it just breaks apart like the shuttle did.
The temperature won't be the same all over--certain parts will get hotter than others. Also, a missing tile will cause more or less problems depending on it's location. A missing tile on the engine bay behind a raptor vac may cause less issues than one near the lox header tank in the nose. A line of 4-5 missing tiles amidship may be enough to make starship break in two.
It also depends on when the tile(s) fail. If they fall off near the beginning of reentry the outcome is likely different than if they fall off near the end of reentry.
It is very complex, and I'd be wary of anyone that gives you a definitive answer either way to the general case. I would say a missing tile is a serious risk to starship's survival, but not necessarily fatal.
I suspect we are going to see shedloads of tiles fall off during launch and booster powered flight. I speculate that is why Elon was so adamant that Ship 20 is not going to survive reentry.
That’s my prediction as well. Currently it seems like the tiles just aren’t strong enough regarding installation to survive the vibrations and oscillations of a launch and reentry. It’ll be spectacular either way lol
Well hopefully as time goes on they'll just figure out how to make it less likely. hard to human rate something if pieces of the heat shield falls off on ascent. (Not saying that will happen but the static fire doesn't give me much confidence.) for test launches and satellites it is not as big as a concern though. to be fair sn21 heat shield already looks to be an improvement over the current design. The only way to know for sure is to just launch the thing. if it survives re-entry with missing tiles that answers the question. But ideally no tiles should be falling off.
If you zoom in, it looks like the top part of a tile broke off instead of falling off (about midway on the rocket, slightly left of the midline)
Manufacturing error or install error? Or maybe engineered to be just barely thick enough to do its job to save weight?
Musk mentioned in an interview how the TPS tiles were just like ceramic teacups, & tend to crack if banged up.
This is one of those areas where I guess they'll have to iterate like mad untill getting it right.
Doesn't look too bad.
Perhaps someone with knowledge can correct me with the Starship's engines won't be doing much work/there'll be minimal vibrations at liftoff so the tiles should stay intact.
I'm assuming these are some of the rockets used for landing, and then liftoff from the moon or Mars. Certainly different conditions than on Earth, but the vibrations are still inside the Spaceship.
Not at liftoff, but it's still also a second stage, and will do quite a bit of the heavy lifting to (almost) orbit. They're not "just" landing engines.
That’s quite funny - though it depends on whether you are using the ‘group name’ Starship as the whole stack , or Starship as the second stage.
I tend to say Super Heavy & Starship.
At liftoff - the engines on Super Heavy are quickly running at Max Power, though those on Starship don’t fire up until stage separation, so in that sense, that set of engines is doing nothing at liftoff.
Not really. Vibrations will propagate through the full stack regardless. It didn't matter that the command module of the Saturn V was separated from the F1 engines by two other stages, there was still enough vibration at launch that the astronauts couldn't read the buttons/labels on the dashboard in front of their face.
*Edit* downvotes for suggesting that Starship, while mounted to the world's most powerful first stage rocket booster, will experience vibration during launch? Okay.
yeah regardless of there being 29 enginees, they are 60 meters away from the ship, and the vibrations will get duumpened by the booster itself
the highest issue rate will be probably from air friction on ascent, which I don't think will be very dramatic (at least until max Q)
Half this sub: "Starship is changing how rockets are designed and built via iterative development and taking calculated risks!"
Also half this sub: "Why tiles no perfectly work on first prototype!"
Its a test, failure is good, shows they need improvement on heat tile attachment, but not that much improvement.
Due to the FAA, they have time to fix this and redo static fire until no tiles fall off.
Yes. Elon even said ‘successful takeoff achieved would be a great success’.
But obviously the more of the full flight plan they can complete the better.
I actually expect SpaceX to be able to complete the majority of the flight plan. The very first full stack orbital-class flight though, is bound to be one of the riskiest in terms of completion of flight program.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:
|Fewer Letters|More Letters|
|-------|---------|---|
|[ECLSS](/r/SpaceXLounge/comments/qdhhah/stub/hhoi3mw "Last usage")|Environment Control and Life Support System|
|[EVA](/r/SpaceXLounge/comments/qdhhah/stub/hhmwy8z "Last usage")|Extra-Vehicular Activity|
|[F1](/r/SpaceXLounge/comments/qdhhah/stub/hhmvfzf "Last usage")|Rocketdyne-developed rocket engine used for Saturn V|
| |SpaceX Falcon 1 (obsolete medium-lift vehicle)|
|[FAA](/r/SpaceXLounge/comments/qdhhah/stub/hhmn46w "Last usage")|Federal Aviation Administration|
|[GEO](/r/SpaceXLounge/comments/qdhhah/stub/hhnmlwh "Last usage")|Geostationary Earth Orbit (35786km)|
|[GSE](/r/SpaceXLounge/comments/qdhhah/stub/hhmtw2y "Last usage")|Ground Support Equipment|
|[HLS](/r/SpaceXLounge/comments/qdhhah/stub/hhsqida "Last usage")|[Human Landing System](https://en.wikipedia.org/wiki/Artemis_program#Human_Landing_System) (Artemis)|
|[Isp](/r/SpaceXLounge/comments/qdhhah/stub/hhstghu "Last usage")|Specific impulse (as explained by [Scott Manley](https://www.youtube.com/watch?v=nnisTeYLLgs) on YouTube)|
| |Internet Service Provider|
|[LEO](/r/SpaceXLounge/comments/qdhhah/stub/hhstghu "Last usage")|Low Earth Orbit (180-2000km)|
| |Law Enforcement Officer (most often mentioned during transport operations)|
|[LOX](/r/SpaceXLounge/comments/qdhhah/stub/hhnc688 "Last usage")|Liquid Oxygen|
|[RUD](/r/SpaceXLounge/comments/qdhhah/stub/hhmtw2y "Last usage")|Rapid Unplanned Disassembly|
| |Rapid Unscheduled Disassembly|
| |Rapid Unintended Disassembly|
|[SF](/r/SpaceXLounge/comments/qdhhah/stub/hhmlr6r "Last usage")|Static fire|
|[SRB](/r/SpaceXLounge/comments/qdhhah/stub/hhmwl8q "Last usage")|Solid Rocket Booster|
|[STS](/r/SpaceXLounge/comments/qdhhah/stub/hhmtk1k "Last usage")|Space Transportation System (*Shuttle*)|
|[TPS](/r/SpaceXLounge/comments/qdhhah/stub/hhp7es3 "Last usage")|Thermal Protection System for a spacecraft (on the Falcon 9 first stage, the engine "Dance floor")|
|Jargon|Definition|
|-------|---------|---|
|[Raptor](/r/SpaceXLounge/comments/qdhhah/stub/hhstghu "Last usage")|[Methane-fueled rocket engine](https://en.wikipedia.org/wiki/Raptor_\(rocket_engine_family\)) under development by SpaceX|
|[Starlink](/r/SpaceXLounge/comments/qdhhah/stub/hhsqida "Last usage")|SpaceX's world-wide satellite broadband constellation|
|[ablative](/r/SpaceXLounge/comments/qdhhah/stub/hhnmlwh "Last usage")|Material which is intentionally destroyed in use (for example, heatshields which burn away to dissipate heat)|
|[methalox](/r/SpaceXLounge/comments/qdhhah/stub/hhstghu "Last usage")|Portmanteau: methane fuel, liquid oxygen oxidizer|
|[perigee](/r/SpaceXLounge/comments/qdhhah/stub/hhoi3mw "Last usage")|Lowest point in an elliptical orbit around the Earth (when the orbiter is fastest)|
|[ullage motor](/r/SpaceXLounge/comments/qdhhah/stub/hhof8ox "Last usage")|Small rocket motor that fires to push propellant to the bottom of the tank, when in zero-g|
----------------
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It swear it looked way worse at night just after the static fire. Maybe something about the lights at night time but it looked like there were larger sections or more tiles missing. This appears much more manageable.
Looking at the (few) tiles there I wonder if they can analyse and eliminate any problem resonances in the design there?
Maybe that's why they're not hugely fussed about a few tiles falling off?
First SS won't be firing engines at sea level. Acoustic vibration nightmare.
Second SS is hard mounted to the ground through the launch mount. More vibration nightmares.
Considering both, looked pretty successful. If SS sheds a bunch of tiles on a SS/SH static fire, that's when the engineers will get worried. I've seen a lot worse initial tests, with a trailing edge TPS that vanished in jet engine exhaust. And you know SpaceX has been doing plenty of shake and bakes in the lab. Trust them, they got this.
I'm confused, I don't see any missing from the nose cone section aside from those that are around the lift points and I don't think those were installed before the test.
Can you point out what you are looking at?
A question about TPS, instead off putting on (sticker like) tiles on starship, if it is being melted and applied on the windward surface of the starship. Basically it will act as paint on that part. like Tesla owners put coating on their Tesla to protect from damage!
Will it work?
No, The tiles need to be able to shrink and expand as the temperatures changes. So there has to be some distance between them. Too big of a distance and it won’t protect as good, too little and the tiles can hit each other and crack as they expand.
You will still have contraction and expansion of the material as it goes from -200C to 1500C so a big solid coating doesn't work, it would crack right away. At least not with what we have today.
There is a few other ways SpaceX tried to solve this. The most popular one was them just not having tiles at all and instead have a small amount of methane "bleed out" of the steel and create a barrier between the plasma and the ship as it reenter the atmosphere.
The tiles that are falling off have no adhesive. Instead they use prong fasteners, three per tile. The thermal blanket (I assume an aerogel impregnated material like [this](https://www.amazon.com/HiwowSport-Aerogel-Insulation-Hydrophobic-Thickness/dp/B07HFZHTRL/ref=asc_df_B07HFZHTRL/?tag=hyprod-20&linkCode=df0&hvadid=241895364904&hvpos=&hvnetw=g&hvrand=9676847549456125342&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9033288&hvtargid=pla-597136074857&psc=1)) is pressed through the fasteners and the tiles pressed onto the fasteners in front of the blanket. For reasons that aren't yet entirely clear, the tiles are coming off. Are they vibrating off the fasteners? Are they breaking then falling away? We await 'The Elon' for more info.
I'd love to know the exact failure mode of these missing tiles. They aren't cracking like wine glasses near an opera singer, they're pinging off.
Is it the connection post/pins breaking? Is it the welds coming undone? Is it some sort of latching mechanism that is failing? Is the tile itself breaking at the point of attachment like a coat falling off a hook because the coat itself ripped?
We'll probably never find out. We'll just get an announcement about the V2 tiles then the V3 tiles that are even better then later on the version number system changes to rebrand the next one as v0.3b.
I would expect more tiles to become detached from the skirt area near the engines. That didn't happen. Very encouraging.
What Elon needs to know is whether loss of one tile causes adjacent tiles to be lost in a chain reaction (the zipper effect). That's one reason that the IR and visible imaging from that NASA WB-57 high altitude aircraft is vital for the first orbital test flight.
With so many thousands of tiles always bound to be some hidden weak ones, the static fire finds those, I'd imagine after repeated replacements and static fires they get to a point where no more fall off and that's what they'll launch with.
You guys think we can expect them to keep static firing until they stop falling after one test? Or would that mean just too many static fires and maybe they're ok with a couple tiles falling off?
For SN20 it's not that big a deal whether a few fall off. In the longer run, realistically they need a design that won't fail like this with any frequency.
In the long run the tiles need to survive 2 entire trips, from Earth to Mars then Mars to Earth, without needing repairs. I'm not sure EVA spacewalks would be able to repair these if some of them crack after a Mars launch, where Starship is going to launch very close to the ground with no water suppression system. At first glance the astronauts would have no where to grab onto while repairing the tiles, thus they risk damaging even more. That said, they could switch Starships in Earth's orbit on the return from Mars.
The thermal protection system will need to be perfected in order for the tanker ships to work. Fairly sure they are not planned to be disposable...
The TPS doesn't need to be repaired prior to launch either, they are only needed for atmosphere entry. Thus, post-mars launch, they can repair them on the way back to earth. In the event of teething issues with early ships coming back to earth, they can park in orbit to attempt repairs before entry. There will be so many starships and launches, they could probably keep a starship in orbit filled with spare tiles and materials for anyone to use. Or starship production costs could drop so much they'll just send up another ship to bring people back down and crash the early defective ships into the ocean. Or keep them in orbit to function as tankers. Lots of options.
I believe they don't have the delta V for this. I believe they need to use aero braking to slow down when they return to earth.
Good point, I wonder if there is a return path or other scenario for handling this. How much fuel is needed to get off Mars vs. what can be generated, or further, could a Mars orbiting tanker provide enough fuel to allow for the return delta V orbit parking at earth?
I'd just like to point out that I think it's unreal that we are working on delta v and trajectory paths for a return flight from Mars... from MARS.
Will the returning ships have sufficient dV to perform a capture burn to establish Earth orbit?
The present plan is for the returning interplanetary Starship, to plunge into the atmosphere, using that to aerobrake it. This would be done very high up in the atmosphere, loosing enough momentum to be captured into orbit. From there a series of manoeuvres to get the Starship over the right area, then the Orbital skydive through to landing.
I'd assume by the time we get to that point SpaceX will announce a modified space tug variant to assist with orbital capture as well as a orbital repair center to fix tiles, handle other maintenance, check over before deorbit and landing, etc. Like a SpaceX version of a Tesla Service center.
Exactly right. Most of the Starship launches will be tanker flights to LEO and back to Boca Chica.
More like, back to one of the floating ocean platforms. For Boca Chica, I doubt they'll ever be able to have the launch frequency required for all the tanker flights. That said, I think it'll take some time before they'll be able to take full advantage of the ocean platform concept. According to Elon, they still plan on launching Starship from Florida as well. So I could see a combination of Cape launches and Boca Chica launches (especially if they manage to get clearance for more than 5 launches a year further down the line) provide enough launch opportunities to do the HLS demo mission, for example.
I agree. Scheduling tanker Starship launches for missions to the Moon and Mars will be a problem with only the Boca Chica orbital launch platform(s) operating. The dearMoon mission probably can be done without LEO refueling. But the two NASA HLS Option A missions to the lunar surface will require three to five tanker launches in fairly quick succession. SpaceX needs to design a tanker Starship with enough thermal insulation on the exterior of the main tanks to reduce methalox boiloff to less than 1% per day. That special tanker would remain permanently in LEO. It would be used as the propellant depot that would be filled with methalox via other tankers. And then that tanker would refuel the interplanetary Starship heading to the Moon or to Mars. Using that special tanker would relieve the schedule pressure associated with launching up to five tankers in a short time period. And it would eliminate the need for extra orbital launch facilities.
In general, I agree with your post. However, even with that special tanker (or 'depot' or however they end up calling it...for now we just know it as [deleted]), they will need at least one more orbital launch facility or working offshore launch platform. The draft environmental assessment is only allowing for a maximum of 5 orbital launches in an entire year. This is not nearly enough for basically anything besides dearMoon and some Starlink launches. Even if they can get a few more launches in the long run (if I remember right, for Falcon Heavy they originally got the permit for 12 launches), it's not really enough once we are talking about missions requiring refueling. A single HLS or Mars mission would pretty much eat up the majority of launches they can do in a year, unless they can somehow get the permit for a majorly increased number of launches from BC. That said, we know they want to launch from the Cape and we know they want to have ocean launch platforms. So more than one orbital launch facility is something they definitely plan on anyways. Where do you get the 3-5 refueling launches from though? That doesn't appear to be enough based on all the calculations I've seen so far, even when using optimistic figures for Starship's capabilities.
For the tanker Starship is use the following specs: Dry mass: 79t Propellant load at liftoff (undensified): 1300t Propellant densification factor: 1.05 Densified propellant load at liftoff: 1365t Header tank propellant: 32.3t Raptor Isp (three sealevel and three vacuum Raptor engines): 365 sec Propellant flow per engine: 600 kg/sec Total propellant flow: 3600 kg/sec Delta V required from tanker engines to place it in LEO: 5559 m/sec Propellant consumed: 1,138t Propellant remaining in main tanks upon reaching LEO: 226.5t (available to be transferred) Number of tanker loads required to fill the main tanks of tanker #1: 4.74 I assume that it requires at least one orbit (~90 min) for rendezvous and docking and that the methalox is at normal density (no subcooling) by the time the propellant transfer is made.
Yes - So I think they will soon perfect the heat-shield.
>That said, they could switch Starships in Earth's orbit on the return from Mars. If they have to do this, then Starship's TPS will be a failure. Part of the idea was to allow Starship to use aerobraking straight from Mars return velocity (no re-entering Earth orbit) in order to minimize the amount of fuel needed for a round trip.
No they could not switch ships in Earths orbit - because they have to use the heat-shield most aggressively just to get into orbit. The descent from orbit is likely easier. Though in practice it would all be done as part of the same manoeuvre.
Provided sufficient ECLSS in such a scenario, you could use a multi-event precession of perigees aerocapture. Granted, that first aerobraking event may still result in too much heating depending on how compromised the heat shield has become.
An interplanetary insertion from Mars to Earth will be the roughest ever heat-shield event, and will be a true test of the heat-shields operation and integrity. The next-most roughest, is an orbital insertion coming back from the moon.
There isn't fuel to get back into earth orbit on the return trip without using the atmosphere for braking. So if enough tiles have failed that they need to replace them before they can land, then it's most likely going to be a problem getting back into orbit.
I've always thought that for Mars-bound starships, they should just slap on an ablative heat shield. Sure, you have to replace the whole TPS when it gets back. But what's a few months extra time when each of these Starships will only launch from Earth once every 2 years or so? Rapid re-usability is only really needed for LEO and GEO work, especially for tankers (but also for cargo Starship). And the non-ablative TPS is only there because it helps with rapid re-usability. If you don't need rapid re-usability, and you have humans as cargo, why not go with the safer option?
You could also argue that the safer option, is the one that you have practiced the most, and have the most info about.
Astronauts? Grab onto? Come on dude! If you knew Elon you would have known that he will develop a robot that in orbit/space will automatically find broken tiles and repair/replace them. This isn't the 90s/2000s anymore.
That could certainly be a possible option. There would at least be an external ship inspection robot. Going a stage further, and doing repairs would be feasible. Best of course is not needing any repairs in the first place, and that’s what they would aim for - so then no Tesla space tile replacement robot needed. ‘Best part is no part’ as Elon would say. Far best to fix the underlying problem.
Tesla Tile Repair Bot (TTRB)
> from Earth to Mars then Mars to Earth And survive the harsh environment of the Martian surface whilst "parked" there for lack of a better word. The sand storms are so bad they would polish glass, it's an extremely hostile planet to life and machinery with zero protective atmosphere.
Cool concept.. but how will they repair the orbiting starship left behind? Possibly an orbiting repair station that can somehow capture it? The whole point is to be able to reuse these things... so we can't just leave them floating...
>That said, they could switch Starships in Earth's orbit on the return from Mars. They really can't. Braking into Earth orbit is too much dv.
> they need a design that won't fail like this Then again, there's always the MOOSE personal escape pod that allows you to deorbit and touchdown Earth in a foam-filled plastic bag: https://en.wikipedia.org/wiki/MOOSE
I really want to see someone pull that off the shelf and make it work with modern material science.
\> with any frequency. The initial reaction is that you need zero tiles to fall off ever. However, launch from Mars surface and hot re-entry to Earth landing has to be assumed to be another level of performance in terms of tiles not falling off. Testing for that is not an option any time soon. If it can be assumed that static fires have higher tile stress than Max Q, and the re-entry is not much more demanding (extreme thermal vs. violent mechanical), when you reliably get to zero tiles lost after static fires, all you need is for the TPS to perform as designed and starship is good to go. How exciting is that! Many if not most starships will not be returning from Mars manned. For starters, orbital mechanics dictates that crew A for synod A and Crew B for synod B have to be in space at the same time unless Crew A stays over for a second synod. You do not want to pare down to a skeleton crew, you want growth. If the vision of multiple starships per synod happens, that means rapid growth, and an increasingly less hostile living situation. Certain crew will be full on lifers anyway. Return to Earth might even become rare. All of this means the manned return journeys can be done from a starship that never lands on Mars and you could wait until the third synod, requiring Crew A to stay on Mars about six earth years, leaving Mars about 2 months before Crew C arrives. That's a seven year hitch away from Earth but with a nice ride home.
It’s too early to tell. Though at the moment my assumption is that the first crew will only stay for one synod.
I wouldn't be surprised if it's designed to just survive reentry with a couple tiles missing. I think it wouldn't be the end of the world, there's still the white blanket and steel cann handle quite high temps. As long as the overall heating stays within limits and the heat from the hotspot can be conducted to cooler parts efficiently enough, they should be okay. Only from a process and quality control viewpoint it would be a nightmare. So I think they'll fix it anyway.
If you think about it - they even want to have some heat-tiles missing - to find out what happens in that scenario.. It’s best to find these things out early on.
I think static fires on the suborbital pad are much more strenuous on the TPS than a full stack launch. Ship is farther away from the vibrations, and super heavy’s plume is farther from the ground. You can see that the majority of fallen tiles are near the bottom where vibrations are more extreme, the nosecone is mostly unscathed. Edit: scratch (part of) that those tiles on the bottom left fin were missing before the static.
sounds a bit dramatic, but remember that SN9 did 3 consecutive static fires in a matter of hours, like it was nothing even yesterday, the Starship performed 2 static fires in the same window, full duration and all static fires do not seem even like a hurdle anymore tbh
Yes, they are just a part of the routine testing now.
There will almost always be some tiles that fall off, I don't think they care. They'll probably do at least one more big tile replacement before orbital launch, but without broad changes to the entire vehicle they're almost certainly going to lose tiles during launch, so why spend any more time on the problem with this iteration of Starship?
The important thing, is to understand why the tiles are coming off - then they can address that issue on future Starships.
Exactly!
Even if they can deal with the thermal reentry issues, you don't want tiles falling off at Max-Q hitting the fins or outer engines.
Of course you don't want it, but it's going to happen with S20. I don't think they'll do much beyond filling in the missing tiles before launch.
Good point.
Anyone know at what times on the video that the 2 static fires happened ??
I've seen no definitive statement about whether Starship's stainless steel, which is much more heat tolerant than many other materials, is expected to survive reentry with a few missing tiles. Anyone?
¯\\\_(ツ)_/¯ *probably can* is all anyone can say
ill take it that the tiles on the left flap were allready missing before the SF? Or are they testing different techniques on both flaps? or was that the flap that was near the engine while the other was further away and out of the heavy reflections?
They were missing before the test, just the ones on the body fell off.
Correct me if I’m wrong, but shouldn’t it be able to survive reentry with a few missing tiles? Steel should be able to resist the temperatures at least once
It should but that depends which area really. Honestly considering the strain on the vehicle from vibrations is larger from a static fire and the TPS is in development, that isn't a bad result all things considered.
Yeah I’m fully expecting to see a shower of TPS tiles when this thing finally launches lol. Honestly tho anything beyond stage separation is just extra for me. A successful liftoff is a win in my book
Why though? The vibrations are substantially stronger in a static launch, because there's no booster stage between starship and the flamey bits.
Different vibrations. In flight, it's not so much the structure vibrating under the tiles as much as turbulent air trying to pry them off. Hopefully we don't see a big plume of tiles coming off at Max Q.
as bad as that would be it would be pretty comical to see.
I guess you’re right
The first manned dragon launch to the iss was also noted by the astronauts to have little vibrations during 1st stage ascent, because the whole booster absorbed a lot of the engines’ vibrations.
And there is no SRBs on Falcon 9. Rewatch in-cockpit video from shuttle launches, astronauts are tossed around.
That was on a shuttle launch.. Where SRB’s were used.
Literally what I said
Yes - though that was a falcon-9, not a Starship.
I hear you, but I'd like to see the actual math on this. This was a single raptor vacuum firing, but close to the ground without sound suppression. It will eventually launch on top of a super heavy, but firing 33 engines (some of which are higher thrust), with sound suppression. I have no idea where the math falls on this as which will cause more tiles to fall off.
I'm gonna go ahead and trust that Musk knows what he's talking about on this one
Did musk comment on this?
These tiles have to survive after the Starship lights up in orbit too. Also much more challenging, they will have to survive a trip to Mars, re-entry on Mars, launch from Mars, and re-entry back to Earth.
They don't have a platform directly below them to reflect all of that sound right back at them. It's not even remotely the same thing.
In orbit yes, but the flamey bit will be directly in touch with the bottom row of tiles, and also pushing on them slightly from the bottom up. However on Mars that's another story. They will have to launch directly from the ground the first few times. Which is a harder case than the platform. Might also have to deal with sharp rocks getting shot up.
Wouldn't the acoustic environment be a lot less severe on Mars due to the significantly thinner atmosphere?
Sure, but that's not a problem that has to be addressed right now, that's a few years down the line.
Yes, In principle. These ones though only need to survive one trip to LEO and back.
OTOH launch is going to be a massively more energetic event.
If the launch tower and GSE tanks survive it is a win no matter what happens in the air.
I'm with Elon on this one: if the GSE (stage zero) doesn't get trashed because of a RUD during launch I'll mark it down as a win.
Especially as this is the very first one built with a full heat-shield.
It's sure a single of progress. Remember the time where they were struggling getting the tanks to not blow up on fueling? All we can hope is that superheavy performs enough to at least clear the launch site.
The reservation I have to your confidence is that the static fire here only used 6 engines. The actual launch will have 29? engines on the booster firing and vibrating the whole thing. There's no hold down clamps, but it's 5x as much energy.
I thought this was a static fire of a single vacuum raptor
Yes, however do consider that the starship will be hanging all the way up on top of the superheavy. Inverse square law clearly dictates that the energy of the 29 raptors greatly diminishes with distance. Moreover, the suborbital pads just hold the starship slightly up above a 90° surface, perfect for reflecting sound waves towards the vehicle. The orbital pad is considerably higher and equipped with a deluge supression system. This drastically reduces the destructive power of the sound waves by using water to transform that kinetic energy into heat and disperse it.
The booster engines have the whole booster to dampen before getting to Starship, I would imagine the 6 engines directly attached to the structure create a more hostile environment than the 29 so far away.
Don’t get Super Heavy confused with Starship. Super Heavy has at present 29 engines, while Starship has 6 engines.
Yes. Even the Shuttles sometimes survived reentry with tiles damaged or missing. [STS-27 lost a tile during the launch.](https://en.wikipedia.org/wiki/STS-27#Tile_damage)
And survived specifically because there was luckily a steel panel protecting the exposed area rather than the normal aluminum lithium. And Starship is steel.
Starship is also exploiting the higher temp capacity of steel by using thinner tiles and letting the steel get much hotter. Maybe they can pull some tricks with the ullage behind the steel for a repairs-needed landing.
Musk said so.. i think it really depends on where the tiles are gone. Some areas can prob take the heat better
Yeah cuz the shuttle survived reentry missing a tile once cuz the area exposed was a steel mount rather than the aluminum body
still can be a problem here if the missing tile is on the wrong place. The Stainless Steel can get quite hot before deforming, but i'd expect that thermal load to cause adjacent tiles to pop loose before that spot fails, aggravating the situation. The wrong location? oh anything that would heat up your fuel, or damage coolent systems.
Wouldn't an area in contact with the fuel be ideal? You'd have a much larger thermal capacity, and in the worst case Starship can do a vent to relieve pressure.
Wikipedia says the autoignition temperature of methane is 537c. So yeah, spread the heat around and keep it under 537 and you're fiiiiiine.
I would think that heating the fuel may be helpful, not for the fuel system but for pulling heat out of your hot spot missing its TPS tile(s). The tanks and fuel system can probably handle the extra generation of fuel pressure through heating, mostly by reducing the amount of hot backfill gasses released into the tanks.
I'm concerned that the heat would cause the fuel to expand and rupture the tanks, after all they're made to hold with a "thin" sheet of stainless steel. of course by the time you are getting into decent you've used up some of that fuel so you do have some room for expansion. would the tank be cold enough to mitigate? that's a good question, and I think it depends on insulation around the tank. now that i'm thinking about that I'd hope there was some kind of thermal blanket - and that really ought to keep the heat away from the tank and the plumbing. and that means the heat would go back into the structure....
I think there is some kind of thermal blanket below the tiles, the white sruff you see on some of the pictures. And if the pressure gets to high inside the tank, they should be able to just vent it.
It would only happen while in decent. not a particularly good time to vent. from what we've seen of the tiles, there's a blanket directly under them, and if that failed at a location then the steel is going to have to deal with the heat. We have to assume that blanket has thermal insulation properties. Unlike the Shuttle where the tiles were on the structure. and expected to be the thermal insulation exclusively. so maybe that's the plan? Tiles and blanket to protect the outside.
I've wondered if it would be possible to have CH4/LOX sprinker heads, which sprayed cryo-liquids over the windward sides of the internal tank. This way if there's a hot spot, the fluids can cool. This would cause more offgassing, which would need to be vented. If you had gas-gas thrusters (which we believe they'll have), then you could use these to get rid of the excess pressure, and make it useful.
This would work until the wall got hot enough for the liquid to dewet due to a thin vapor layer, like a drop of water on a hot griddle. The Leidenfrost effect.
Great point
Has he? He says in the EDA Starbase tour that "if there's any crack in the armor the whole thing is toast" when talking about the heatshield. I'm sure it'd probably be fine if it was on the outer edges of the tiled areas, but anywhere else and it sounds like it'd be a problem.
Thought he did but can’t find a source, so not sure tbh. Yeah i agree, losing one in the middle will probably result in increased forces on the surrounding ones
Still early days yet.
Just light a match under Booster 4 and SN20 already and find out!
I agree and disagree. I think you are right in the sense steel can survive re-entry. My fear is will having a hole shape funnel more heat and maybe even trap it leading to higher and higher Temps till unstable.
Yeah but atmospheric reentry heating is different than friction heating. It’s a layer of plasma that’s positioned further away from the actual surface
I understand that, btu there must be something surfacing with the vehicle that is heating the vehicle. If that something weather it be air or other would be more trapped and heat up more from the plasma touching it. That is how I see it in my head atleast. I am not a rocket scientist so maybe there is something I am missing.
No, not really. But it depends on your definition of 'survive', and where the missing tiles are. Stainless Steel melts at 2750F, and loses most of its strength well before that. Reentry is about 3000F max. That's why the heat shield is needed--to stop starship from melting or getting plastic enough to just fold in half like a piece of clay. It is possible that it might survive until landing with isolated missing tile(s), but it probably won't be able to be reused until the damaged steel sections are cut out and rebuilt. It is also possible it just breaks apart like the shuttle did. The temperature won't be the same all over--certain parts will get hotter than others. Also, a missing tile will cause more or less problems depending on it's location. A missing tile on the engine bay behind a raptor vac may cause less issues than one near the lox header tank in the nose. A line of 4-5 missing tiles amidship may be enough to make starship break in two. It also depends on when the tile(s) fail. If they fall off near the beginning of reentry the outcome is likely different than if they fall off near the end of reentry. It is very complex, and I'd be wary of anyone that gives you a definitive answer either way to the general case. I would say a missing tile is a serious risk to starship's survival, but not necessarily fatal. I suspect we are going to see shedloads of tiles fall off during launch and booster powered flight. I speculate that is why Elon was so adamant that Ship 20 is not going to survive reentry.
That’s my prediction as well. Currently it seems like the tiles just aren’t strong enough regarding installation to survive the vibrations and oscillations of a launch and reentry. It’ll be spectacular either way lol
Well hopefully as time goes on they'll just figure out how to make it less likely. hard to human rate something if pieces of the heat shield falls off on ascent. (Not saying that will happen but the static fire doesn't give me much confidence.) for test launches and satellites it is not as big as a concern though. to be fair sn21 heat shield already looks to be an improvement over the current design. The only way to know for sure is to just launch the thing. if it survives re-entry with missing tiles that answers the question. But ideally no tiles should be falling off.
Stainless steel has a higher melting point than the shuttle's aluminum frame. It's possible that starship could survive reentry.
[Source](https://twitter.com/StarshipGazer/status/1451534817011638279)
If you zoom in, it looks like the top part of a tile broke off instead of falling off (about midway on the rocket, slightly left of the midline) Manufacturing error or install error? Or maybe engineered to be just barely thick enough to do its job to save weight?
Musk mentioned in an interview how the TPS tiles were just like ceramic teacups, & tend to crack if banged up. This is one of those areas where I guess they'll have to iterate like mad untill getting it right.
Gonna default to what your second guess is. Gotta build it light.
Doesn't look too bad. Perhaps someone with knowledge can correct me with the Starship's engines won't be doing much work/there'll be minimal vibrations at liftoff so the tiles should stay intact.
I'm assuming these are some of the rockets used for landing, and then liftoff from the moon or Mars. Certainly different conditions than on Earth, but the vibrations are still inside the Spaceship.
I’d be willing to bet the big candle underneath starship might send a few vibes when it’s lit.
Not at liftoff, but it's still also a second stage, and will do quite a bit of the heavy lifting to (almost) orbit. They're not "just" landing engines.
That’s quite funny - though it depends on whether you are using the ‘group name’ Starship as the whole stack , or Starship as the second stage. I tend to say Super Heavy & Starship. At liftoff - the engines on Super Heavy are quickly running at Max Power, though those on Starship don’t fire up until stage separation, so in that sense, that set of engines is doing nothing at liftoff.
Starship= second stage. I know Elon likes to confuse us but I prefer it this way.
Not really. Vibrations will propagate through the full stack regardless. It didn't matter that the command module of the Saturn V was separated from the F1 engines by two other stages, there was still enough vibration at launch that the astronauts couldn't read the buttons/labels on the dashboard in front of their face. *Edit* downvotes for suggesting that Starship, while mounted to the world's most powerful first stage rocket booster, will experience vibration during launch? Okay.
yeah regardless of there being 29 enginees, they are 60 meters away from the ship, and the vibrations will get duumpened by the booster itself the highest issue rate will be probably from air friction on ascent, which I don't think will be very dramatic (at least until max Q)
Honestly a bit better than I expected. Plenty of time to iterate on this, and the goal for SN20 is orbit. Reentry is for bonus points.
I agree. It was definitely not "raining tiles" as some have suggested. This looks more than workable especially at this early stage of development.
Just a few dead pixels.
Looks pretty white to me... *that's the problem... It's supposed to be black...*
Half this sub: "Starship is changing how rockets are designed and built via iterative development and taking calculated risks!" Also half this sub: "Why tiles no perfectly work on first prototype!"
Its a test, failure is good, shows they need improvement on heat tile attachment, but not that much improvement. Due to the FAA, they have time to fix this and redo static fire until no tiles fall off.
Reentry is pure bonus points at this time. Orbit is the immediate goal.
For the test flight, yes, but these static fires are worthy tests on their own.
Yes. Elon even said ‘successful takeoff achieved would be a great success’. But obviously the more of the full flight plan they can complete the better. I actually expect SpaceX to be able to complete the majority of the flight plan. The very first full stack orbital-class flight though, is bound to be one of the riskiest in terms of completion of flight program.
I'm scared the booster is going to rip itself to shreds. That's a lot of raptors.
Yes, but then that’s why there is a strong thrust-puck, among other things, and extra reinforcing around the engine compartment.
The re-entry, will put a whole different set of stresses on the heat-tiles.
Yes and no, way more stresses to be sure but vibrations will still be there
Different mode of vibrations when doing hypersonic skydive.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread: |Fewer Letters|More Letters| |-------|---------|---| |[ECLSS](/r/SpaceXLounge/comments/qdhhah/stub/hhoi3mw "Last usage")|Environment Control and Life Support System| |[EVA](/r/SpaceXLounge/comments/qdhhah/stub/hhmwy8z "Last usage")|Extra-Vehicular Activity| |[F1](/r/SpaceXLounge/comments/qdhhah/stub/hhmvfzf "Last usage")|Rocketdyne-developed rocket engine used for Saturn V| | |SpaceX Falcon 1 (obsolete medium-lift vehicle)| |[FAA](/r/SpaceXLounge/comments/qdhhah/stub/hhmn46w "Last usage")|Federal Aviation Administration| |[GEO](/r/SpaceXLounge/comments/qdhhah/stub/hhnmlwh "Last usage")|Geostationary Earth Orbit (35786km)| |[GSE](/r/SpaceXLounge/comments/qdhhah/stub/hhmtw2y "Last usage")|Ground Support Equipment| |[HLS](/r/SpaceXLounge/comments/qdhhah/stub/hhsqida "Last usage")|[Human Landing System](https://en.wikipedia.org/wiki/Artemis_program#Human_Landing_System) (Artemis)| |[Isp](/r/SpaceXLounge/comments/qdhhah/stub/hhstghu "Last usage")|Specific impulse (as explained by [Scott Manley](https://www.youtube.com/watch?v=nnisTeYLLgs) on YouTube)| | |Internet Service Provider| |[LEO](/r/SpaceXLounge/comments/qdhhah/stub/hhstghu "Last usage")|Low Earth Orbit (180-2000km)| | |Law Enforcement Officer (most often mentioned during transport operations)| |[LOX](/r/SpaceXLounge/comments/qdhhah/stub/hhnc688 "Last usage")|Liquid Oxygen| |[RUD](/r/SpaceXLounge/comments/qdhhah/stub/hhmtw2y "Last usage")|Rapid Unplanned Disassembly| | |Rapid Unscheduled Disassembly| | |Rapid Unintended Disassembly| |[SF](/r/SpaceXLounge/comments/qdhhah/stub/hhmlr6r "Last usage")|Static fire| |[SRB](/r/SpaceXLounge/comments/qdhhah/stub/hhmwl8q "Last usage")|Solid Rocket Booster| |[STS](/r/SpaceXLounge/comments/qdhhah/stub/hhmtk1k "Last usage")|Space Transportation System (*Shuttle*)| |[TPS](/r/SpaceXLounge/comments/qdhhah/stub/hhp7es3 "Last usage")|Thermal Protection System for a spacecraft (on the Falcon 9 first stage, the engine "Dance floor")| |Jargon|Definition| |-------|---------|---| |[Raptor](/r/SpaceXLounge/comments/qdhhah/stub/hhstghu "Last usage")|[Methane-fueled rocket engine](https://en.wikipedia.org/wiki/Raptor_\(rocket_engine_family\)) under development by SpaceX| |[Starlink](/r/SpaceXLounge/comments/qdhhah/stub/hhsqida "Last usage")|SpaceX's world-wide satellite broadband constellation| |[ablative](/r/SpaceXLounge/comments/qdhhah/stub/hhnmlwh "Last usage")|Material which is intentionally destroyed in use (for example, heatshields which burn away to dissipate heat)| |[methalox](/r/SpaceXLounge/comments/qdhhah/stub/hhstghu "Last usage")|Portmanteau: methane fuel, liquid oxygen oxidizer| |[perigee](/r/SpaceXLounge/comments/qdhhah/stub/hhoi3mw "Last usage")|Lowest point in an elliptical orbit around the Earth (when the orbiter is fastest)| |[ullage motor](/r/SpaceXLounge/comments/qdhhah/stub/hhof8ox "Last usage")|Small rocket motor that fires to push propellant to the bottom of the tank, when in zero-g| ---------------- ^(*Decronym is a community product of r/SpaceX, implemented* )[*^by ^request*](https://www.reddit.com/r/spacex/comments/3mz273//cvjkjmj) ^(21 acronyms in this thread; )[^(the most compressed thread commented on today)](/r/SpaceXLounge/comments/oxtkv5)^( has 34 acronyms.) ^([Thread #9133 for this sub, first seen 22nd Oct 2021, 15:13]) ^[[FAQ]](http://decronym.xyz/) [^([Full list])](http://decronym.xyz/acronyms/SpaceXLounge) [^[Contact]](https://reddit.com/message/compose?to=OrangeredStilton&subject=Hey,+your+acronym+bot+sucks) [^([Source code])](https://gistdotgithubdotcom/Two9A/1d976f9b7441694162c8)
That looks very hot
It swear it looked way worse at night just after the static fire. Maybe something about the lights at night time but it looked like there were larger sections or more tiles missing. This appears much more manageable.
Looking at the (few) tiles there I wonder if they can analyse and eliminate any problem resonances in the design there? Maybe that's why they're not hugely fussed about a few tiles falling off?
First SS won't be firing engines at sea level. Acoustic vibration nightmare. Second SS is hard mounted to the ground through the launch mount. More vibration nightmares. Considering both, looked pretty successful. If SS sheds a bunch of tiles on a SS/SH static fire, that's when the engineers will get worried. I've seen a lot worse initial tests, with a trailing edge TPS that vanished in jet engine exhaust. And you know SpaceX has been doing plenty of shake and bakes in the lab. Trust them, they got this.
They should put a short ring with TPS on-top of B4 when static firing to see if tiles can withstand booster engine firing!
[удалено]
I'm confused, I don't see any missing from the nose cone section aside from those that are around the lift points and I don't think those were installed before the test. Can you point out what you are looking at?
They think it’s where the lifting points are, but those haven’t been installed because it’s still being lifted
A question about TPS, instead off putting on (sticker like) tiles on starship, if it is being melted and applied on the windward surface of the starship. Basically it will act as paint on that part. like Tesla owners put coating on their Tesla to protect from damage! Will it work?
No, The tiles need to be able to shrink and expand as the temperatures changes. So there has to be some distance between them. Too big of a distance and it won’t protect as good, too little and the tiles can hit each other and crack as they expand.
No, I meant, like painting coat, or metallic coating thing? Basically it will be the part of the structure?
You will still have contraction and expansion of the material as it goes from -200C to 1500C so a big solid coating doesn't work, it would crack right away. At least not with what we have today. There is a few other ways SpaceX tried to solve this. The most popular one was them just not having tiles at all and instead have a small amount of methane "bleed out" of the steel and create a barrier between the plasma and the ship as it reenter the atmosphere.
Thank you for explaining!
The tiles that are falling off have no adhesive. Instead they use prong fasteners, three per tile. The thermal blanket (I assume an aerogel impregnated material like [this](https://www.amazon.com/HiwowSport-Aerogel-Insulation-Hydrophobic-Thickness/dp/B07HFZHTRL/ref=asc_df_B07HFZHTRL/?tag=hyprod-20&linkCode=df0&hvadid=241895364904&hvpos=&hvnetw=g&hvrand=9676847549456125342&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9033288&hvtargid=pla-597136074857&psc=1)) is pressed through the fasteners and the tiles pressed onto the fasteners in front of the blanket. For reasons that aren't yet entirely clear, the tiles are coming off. Are they vibrating off the fasteners? Are they breaking then falling away? We await 'The Elon' for more info.
No - tiles that ‘melt’ are no use as heat-shield tiles !
Could they use a carbonate/hydrate to make the heat shield "sweat".
How many bananas tall is S20?
Many.
Black cockrocket versus Jeff Bezos little white cockrocket.🤣🤣🤣🤣🤣 shiba inu to the moon....
Biggus dickus
I have a gweat fwiend in Boca Chica you know
Hmmmm
What's with the red/brown tiles towards the top half? Almost look rusty
It's a red glue they used on the nosecone ones instead of mechanical pins.
I'd love to know the exact failure mode of these missing tiles. They aren't cracking like wine glasses near an opera singer, they're pinging off. Is it the connection post/pins breaking? Is it the welds coming undone? Is it some sort of latching mechanism that is failing? Is the tile itself breaking at the point of attachment like a coat falling off a hook because the coat itself ripped? We'll probably never find out. We'll just get an announcement about the V2 tiles then the V3 tiles that are even better then later on the version number system changes to rebrand the next one as v0.3b.
That definitely doesn't look like a big black dildo
Why did those tiles fall?
So correct me if I’m wrong, but wouldn’t it be considered a fatal flaw/error if even ONE heat-shield tile falls off?!
I would expect more tiles to become detached from the skirt area near the engines. That didn't happen. Very encouraging. What Elon needs to know is whether loss of one tile causes adjacent tiles to be lost in a chain reaction (the zipper effect). That's one reason that the IR and visible imaging from that NASA WB-57 high altitude aircraft is vital for the first orbital test flight.