Starship V2 Versus Space Shuttle Tile damage

[TomH]

Apologies if this was already mentioned and I didn't see it. A major advantage SS has over STS is that SS tiles are standardized size and shape. STS had so many unique pieces in its sort-of jigsaw/tesselation pattern.

[xvel]

not exactly true, starship still has shitload of unique tiles for nosecone, hinges, borders, flaps

[Cabbage123]

SpaceX chose an intentionally difficult trajectory, after intentionally compromising the heat shield, on both Flights 10 and 11 for testing purposes. It definitely looks bad afterwards... But I don't think that necessarily is a bad sign for the program, since we don't know what a normal operations reentry does to the heat shield.

This definitely isn't the final heat shield either.

This is key I think. The heat shield only really needs to be good enough to stop the Starship from blowing up regularly on re-entry, and ideally not requiring too much time to be ready for the next flight. It doesn't need to be perfect on even rapidly moving towards perfect.

The design of the ship is going to be iterating fast enough that we probably won't see a huge amount of reuse of a given ship and, even where we do, it hardly needs to be rapid reuse, just ideally quite quick.

The "final" rapidly reusable over multiple flights heat shield is going to be many years away, and it won't matter if fully reusable is only ever a pipe dream (because you can just have extra ships).

They're learning lessons at the moment, but maybe the key question they want to answer is "based upon current robustness and repair time, how many ships do we need to plan to have, to get to our required cadence?" (the answer being 1, if you can always refuel and go, or a bigger number if you need time to fix and occasionally lose a ship).

[catdlr]

not exactly true, starship still has shitload of unique tiles for nosecone, hinges, borders, flaps

Here are two examples. Bring each up into edit-mode (paint, etc), and be amazed at all the different sizes all along this area alone.  Yes, the main body is made of two sets, one for the rings and one for the expansion area ring sets, where the welding is done, and the tiles in those areas are the same 1/2 half-size.

[xvel]

Of course, in the flap hinge area, each tile is different to fit the hinge cover shape, but what is not so obvious at first glance is that each row of tiles on the nosecone is a different size, decreasing as it moves upward, then switching back to larger tiles several times where these straight lines are.

[Nonexistence]

During the last test they specifically omitted groups of four tiles in the most critical areas and i think they then added a sort of bolt on multi layered plate to retain the underlying layers.

Or am i mistaken?

Under what circumstances would this occur in normal operations?

Dare i suggest an in space repair to prevent peeling back tiles on reentry?
Was this a test of that?

What else?

[Twark_Main]

not exactly true, starship still has shitload of unique tiles for nosecone, hinges, borders, flaps

Here are two examples. Bring each up into edit-mode (paint, etc), and be amazed at all the different sizes all along this area alone.  Yes, the main body is made of two sets, one for the rings and one for the expansion area ring sets, where the welding is done, and the tiles in those areas are the same 1/2 half-size.

What impresses me, upon inspection, is how few different tiles they used to do the job. Anywhere tiles can be a common design, that is what SpaceX has done.

On the Shuttle, literally no two tiles were the same.

[LouScheffer]

I think they need a pathway to full and rapid reusability of the vehicle or it's a failure.  Do they have that pathway or are they trying to invent one as they go?  Otherwise, it's not much different than the Shuttle was.

It's not clear to me that SpaceX *needs* much more from a heatshield than Shuttle had long ago.  Of course SpaceX would love to develop a heatshield that needed no maintenance whatsoever between flights.  But as a backup, as many people have pointed out, an inspect-and-replace robot could potentially result in rapid (even if not fully re-usable) re-use.   Conceptually, this is exactly the same as the shuttle, but designing for this capability (as few tile varieties as possible, pins rather than adhesive for attachment, ablative under tiles to avoid airframe repair, etc.) seems like it could reduce turnaround from a few months to a few days.

An automated inspect-and-replace could be seen as a failure, conceptually no better than a 50 year old design.  But in other ways it could be considered a success, if it enables rapid re-use, even with no advancement of the state of the art in heat shields.

[TomH]

SS tiles are standardized size and shape.

not exactly true, starship still has shitload of unique tiles for nosecone, hinges, borders, flaps

What impresses me, upon inspection, is how few different tiles they used to do the job. Anywhere tiles can be a common design, that is what SpaceX has done.

On the Shuttle, literally no two tiles were the same.

Twark's statement was my intent. I did not say all SS tiles are identical. I said they are standardized. Yes, there are a number of different sizes/shapes, however they essentially are limited to a small number of categories and within each of those categories, all of the tiles are the same. This makes manufacturing and applying them easier than STS. Twark is correct about STS tiles, which remind me of an Inca stone wall. Limiting the number of differing sizes and shapes makes the TPS much simpler.

[Jim]

SS tiles are standardized size and shape.

not exactly true, starship still has shitload of unique tiles for nosecone, hinges, borders, flaps

What impresses me, upon inspection, is how few different tiles they used to do the job. Anywhere tiles can be a common design, that is what SpaceX has done.

On the Shuttle, literally no two tiles were the same.

Twark's statement was my intent. I did not say all SS tiles are identical. I said they are standardized. Yes, there are a number of different sizes/shapes, however they essentially are limited to a small number of categories and within each of those categories, all of the tiles are the same. This makes manufacturing and applying them easier than STS. Twark is correct about STS tiles, which remind me of an Inca stone wall. Limiting the number of differing sizes and shapes makes the TPS much simpler.

Nah.  OV-103 and used 3' x3" blankets on the upper surfaces which were easier to attach.  And all black tiles were manufactured the same way.  They were cut from large stock, they were not molded.  The black coating was done on an assembly line.

[dondar]

SS tiles are standardized size and shape.

not exactly true, starship still has shitload of unique tiles for nosecone, hinges, borders, flaps

What impresses me, upon inspection, is how few different tiles they used to do the job. Anywhere tiles can be a common design, that is what SpaceX has done.

On the Shuttle, literally no two tiles were the same.

Twark's statement was my intent. I did not say all SS tiles are identical. I said they are standardized. Yes, there are a number of different sizes/shapes, however they essentially are limited to a small number of categories and within each of those categories, all of the tiles are the same. This makes manufacturing and applying them easier than STS. Twark is correct about STS tiles, which remind me of an Inca stone wall. Limiting the number of differing sizes and shapes makes the TPS much simpler.

Nah.  OV-103 and used 3' x3" blankets on the upper surfaces which were easier to attach.  And all black tiles were manufactured the same way.  They were cut from large stock, they were not molded.  The black coating was done on an assembly line

The problem is not "manufacturing". (I believe you mean kneading/pressing silicon dough). The problem is exactly precisely cutting and coating with  tetrasilicide individually labeled tiles. All 30k (initially) or 20k (later) of them.
And of course to spend ~2h per square feet in order to glue this "china" to Shuttle. Or to spend ~6h to identify, remove, clean, glue. "Rocket Science".
At every step NASA was spending work hours of qualified engineer job with independent control. Or in other words NASA had permanently employed ~500 people just for TPS.
Time&Money.

[Twark_Main]

SS tiles are standardized size and shape.

not exactly true, starship still has shitload of unique tiles for nosecone, hinges, borders, flaps

What impresses me, upon inspection, is how few different tiles they used to do the job. Anywhere tiles can be a common design, that is what SpaceX has done.

On the Shuttle, literally no two tiles were the same.

Twark's statement was my intent. I did not say all SS tiles are identical. I said they are standardized. Yes, there are a number of different sizes/shapes, however they essentially are limited to a small number of categories and within each of those categories, all of the tiles are the same. This makes manufacturing and applying them easier than STS. Twark is correct about STS tiles, which remind me of an Inca stone wall. Limiting the number of differing sizes and shapes makes the TPS much simpler.

Nah.  OV-103 and used 3' x3" blankets on the upper surfaces which were easier to attach.  And all black tiles were manufactured the same way. They were cut from large stock, they were not molded. The black coating was done on an assembly line.

Right, Shuttle tiles had a complex machining step and every piece needed to be individually tracked. SpaceX has eliminated those complexities.

AFAIK they just de-mold tiles and they're ready to install, correct? Or does the Bakery have any machining steps involved for the standard tiles?

[dondar]

SS tiles are standardized size and shape.

not exactly true, starship still has shitload of unique tiles for nosecone, hinges, borders, flaps

What impresses me, upon inspection, is how few different tiles they used to do the job. Anywhere tiles can be a common design, that is what SpaceX has done.

On the Shuttle, literally no two tiles were the same.

Twark's statement was my intent. I did not say all SS tiles are identical. I said they are standardized. Yes, there are a number of different sizes/shapes, however they essentially are limited to a small number of categories and within each of those categories, all of the tiles are the same. This makes manufacturing and applying them easier than STS. Twark is correct about STS tiles, which remind me of an Inca stone wall. Limiting the number of differing sizes and shapes makes the TPS much simpler.

Nah.  OV-103 and used 3' x3" blankets on the upper surfaces which were easier to attach.  And all black tiles were manufactured the same way. They were cut from large stock, they were not molded. The black coating was done on an assembly line.

Right, Shuttle tiles had a complex machining step and every piece needed to be individually tracked. SpaceX has eliminated those complexities.

AFAIK they just de-mold tiles and they're ready to install, correct? Or does the Bakery have any machining steps involved for the standard tiles?

If the tiles are based on TUFROC (judging by the results spacex tiles are simplified greatly) the process is much more complex than just baking cutting, coating, baking.
TUFROC is two layered sandwich assembled from two very different silicon based slices and is cosplaying compound armour of old ironclads.

[Twark_Main]

It's not TUFROC, as far as we know.

From here:

Starship tiles are based on NASA TUFI (Toughened Unipiece Fibrous Insulation) which was patented in 1989 so the patent will have run out. In any case SpaceX will have access to the technology through a Space Act agreement with NASA.

TUFI tiles were flown on Shuttle starting in 1994 but only on a few tiles in the highest temperature locations. The black reaction cured glass coating on the original tiles has been modified by replacing 20% of the boron tetrasilicide with molybdenum disilicide which should improve the thermal shock resistance of the glass coating.

The general feel of the Starship tiles is that of a rougher product which may well be stronger than the NASA tiles but will definitely be heavier and may conduct a bit more heat. So the glass coating on the Starship tiles varies in thickness while the Shuttle tile has a remarkably uniform coating. The larger diameter alumina fibers that add strength to the fiber matrix on the Shuttle tile are larger again on the Starship tile which adds strength at the cost of more thermal conduction and weight.

Of course the Shuttle tiles were all individually machined for size and thickness whereas the Starship tiles are mostly the same size and thickness across the hull which adds mass but vastly simplifies construction and repairs.

That was about the V1 tiles, and the V2 tiles have smoothed out those quality issues. I don't think they've changed to a completely different technology for V2.

[Chris Bergin]

A good rule to work by is if you have a thumbnail with Elon crying all over it, that's a channel that's like AI slop and written as such. Let's not give them more clicks here. Thread trimmed