Starship heat shield

[john smith 19]

Looking at the possibilities for tiling the flippers it seems the more curves the more tiles required. If they can keep the edges relatively straight it will help minimise the number of tiles required. That said in the battle between aerodynamics and tile count I think aerodynamics wins.

One other thing, with the standard tiles which is the best configuration for the main tile type? Hexagon flat sides aligned upwards or hexagon vertices pointing upwards? Currently the test patch is installed flat side aligned upwards, but I would have thought the other orientation would provide less vertical tile gaps.

TBH at this stage in the game these are early test patches. This articles not likely to go very high or very far.

You're right that wrapping these tiles around a flipper will be tougher if the flipper is curved but the real issue is the edge of the flipper, rather than the acreage.  The question becomes at what scale do yo have a size that can wrap round the edges well enough to not disturb the boundary and not need a massive amount of machining to get a smooth enough OML.

[SteveU]

Couldn´t they just use some material painted... like Starlite? It seems a chemist guy rediscovered the formula and posted it on Youtube... that, or something else.

Even if they are all the same hexagonal tiles, won´t they have to check them all after each landing? Won´t that and replacing any damaged tile still be expensive and labor intensive?

I would think a visual check with camera would be enough.

Now the real question is what would a missing tile(fell off early in reentry) look like for damage.
1. heat would burn through the 4mm steel.
2. heat would permanently weaken steel but no hole.

So if just weakened it could be cut out and patched.

So for a hole and the fact that they have header tanks would this doom the landing? Maybe the depressurized tank would not be able to handle the aero forces?

I doubt they would cut into the tank wall, that just unnecessarily weakens it further.. They could weld a doubler sheet over that spot, and then put a (slightly thinner) tile over the whole mess.

Why not cut out the bad section - no different than the square access holes they are using now.

Still need the doubler around the cutout, so what does it gain?

Sorry - just now able to get back to this.

Besides leaving the damaged material offending my sense of aesthetics - not really sure.

The only possible reason would be if the damaged section might generate cracks.  The cracks may propagate, or cause a section to break off, but that’s pure speculation - don’t know the material properties well enough.

[spacexfanatic]

Couldn´t they just use some material painted... like Starlite? It seems a chemist guy rediscovered the formula and posted it on Youtube... that, or something else.

Even if they are all the same hexagonal tiles, won´t they have to check them all after each landing? Won´t that and replacing any damaged tile still be expensive and labor intensive?

I'm thinking about an indepent one piece heatshield that could be bolt to SS and removed easily so they wont be a lot of time consumming checks. (I think it should be the same for engines).

[sebk]

Couldn´t they just use some material painted... like Starlite? It seems a chemist guy rediscovered the formula and posted it on Youtube... that, or something else.

Even if they are all the same hexagonal tiles, won´t they have to check them all after each landing? Won´t that and replacing any damaged tile still be expensive and labor intensive?

I'm thinking about an indepent one piece heatshield that could be bolt to SS and removed easily so they wont be a lot of time consumming checks. (I think it should be the same for engines).

One large piece doesn't make checks easier. And large single piece would be heavy and close to impossible to manufacture (the only viable option would be soft blanket like material, but no such tech for the temperatures involved has been developed (soft blankets are good for ~1000K like Shuttle leeward, but Stainless steel doesn't need protection against 1000K, it needs protection against 1400-1600K on windward side). Also shield penetrating bolts add difficulty and failure points -- the current small tiles have a smart solution for tat problem: non penetrating snap-on studs.

[spacexfanatic]

Couldn´t they just use some material painted... like Starlite? It seems a chemist guy rediscovered the formula and posted it on Youtube... that, or something else.

Even if they are all the same hexagonal tiles, won´t they have to check them all after each landing? Won´t that and replacing any damaged tile still be expensive and labor intensive?

I'm thinking about an indepent one piece heatshield that could be bolt to SS and removed easily so they wont be a lot of time consumming checks. (I think it should be the same for engines).

One large piece doesn't make checks easier. And large single piece would be heavy and close to impossible to manufacture (the only viable option would be soft blanket like material, but no such tech for the temperatures involved has been developed (soft blankets are good for ~1000K like Shuttle leeward, but Stainless steel doesn't need protection against 1000K, it needs protection against 1400-1600K on windward side). Also shield penetrating bolts add difficulty and failure points -- the current small tiles have a smart solution for tat problem: non penetrating snap-on studs.

I was suggesting multiple heatshields that are interchanged so we don't lose time checking while ideling SS.

Source:courtesy of https://www.lockheedmartin.com

[Nevyn72]

Couldn´t they just use some material painted... like Starlite? It seems a chemist guy rediscovered the formula and posted it on Youtube... that, or something else.

Even if they are all the same hexagonal tiles, won´t they have to check them all after each landing? Won´t that and replacing any damaged tile still be expensive and labor intensive?

I'm thinking about an indepent one piece heatshield that could be bolt to SS and removed easily so they wont be a lot of time consumming checks. (I think it should be the same for engines).

One large piece doesn't make checks easier. And large single piece would be heavy and close to impossible to manufacture (the only viable option would be soft blanket like material, but no such tech for the temperatures involved has been developed (soft blankets are good for ~1000K like Shuttle leeward, but Stainless steel doesn't need protection against 1000K, it needs protection against 1400-1600K on windward side). Also shield penetrating bolts add difficulty and failure points -- the current small tiles have a smart solution for tat problem: non penetrating snap-on studs.

I was suggesting multiple heatshields that are interchanged so we don't lose time checking while ideling SS.

How much time and infrastructure would be required to change out the heat shields on something the size of a Starship? 

[spacexfanatic]

Couldn´t they just use some material painted... like Starlite? It seems a chemist guy rediscovered the formula and posted it on Youtube... that, or something else.

Even if they are all the same hexagonal tiles, won´t they have to check them all after each landing? Won´t that and replacing any damaged tile still be expensive and labor intensive?

I'm thinking about an indepent one piece heatshield that could be bolt to SS and removed easily so they wont be a lot of time consumming checks. (I think it should be the same for engines).

One large piece doesn't make checks easier. And large single piece would be heavy and close to impossible to manufacture (the only viable option would be soft blanket like material, but no such tech for the temperatures involved has been developed (soft blankets are good for ~1000K like Shuttle leeward, but Stainless steel doesn't need protection against 1000K, it needs protection against 1400-1600K on windward side). Also shield penetrating bolts add difficulty and failure points -- the current small tiles have a smart solution for tat problem: non penetrating snap-on studs.

I was suggesting multiple heatshields that are interchanged so we don't lose time checking while ideling SS.

How much time and infrastructure would be required to change out the heat shields on something the size of a Starship? 

 10 tons for heatshield  any respectable overhead crane could manage such a weight.

[john smith 19]

How much time and infrastructure would be required to change out the heat shields on something the size of a Starship? 

Indeed.

I don't think some people realize just how staggeringly big this thing is.

For those who don't go out to an airport and look at a 777 or an airbus 380. the Shuttle was about DC9 sized. Bigger than any previous vehicle, but still quite small.

[rakaydos]

You guys find it easy to colonize Mars and hard to interchange a heatshield? if so I would prefer being more down to earth and let talk about how to put the american flag on the red planet soil before chinese do the same it's more interesting for me than the aspirationals goals (dreams) of EM.

Not just any heat shield, you want a single unitary heat shield, that is also swappable. While being made out of materials chosen for their thermal characteristics, not their durability.

There's a reason the shuttle used tiles, and starship is also using hexagonal tiles.

[RoboGoofers]

10 tons for heatshield  any respectable overhead crane could manage such a weight.

it would be a sail so a building would be needed. And it'd be nearly as flexible as sail cloth. It'd need lots of hands and eyes to apply and verify it was installed properly.

[spacexfanatic]

You guys find it easy to colonize Mars and hard to interchange a heatshield? if so I would prefer being more down to earth and let talk about how to put the american flag on the red planet soil before chinese do the same it's more interesting for me than the aspirationals goals (dreams) of EM.

Not just any heat shield, you want a single unitary heat shield, that is also swappable. While being made out of materials chosen for their thermal characteristics, not their durability.

There's a reason the shuttle used tiles, and starship is also using hexagonal tiles.

Those hexagonal tiles could be fixed to a structure that could be disassembled or fixed to SS, if you won't to operat quickly you won't be able to aford ideling all the spacecraft just because one tile has been damaged and need time to get repaired.

10 tons for heatshield  any respectable overhead crane could manage such a weight.

it would be a sail so a building would be needed. And it'd be nearly as flexible as sail cloth. It'd need lots of hands and eyes to apply and verify it was installed properly.

Please refere to the above response, it must be as easy as interchanging an airliner engine.

[rakaydos]

Rapid inspection of tiles and replacement of only the defective ones is a solvable problem in an era of computer vision.

[Nevyn72]

Please refere to the above response, it must be as easy as interchanging an airliner engine.

Do you know what it takes and how long to change out an airliner engine? 

https://blog.virginatlantic.com/change-aircraft-engine/

[spacexfanatic]

Please refere to the above response, it must be as easy as interchanging an airliner engine.

Do you know what it takes and how long to change out an airliner engine? 

https://blog.virginatlantic.com/change-aircraft-engine/

I saw a documentary on National Geographic it was too easy.

[rakaydos]

Please refere to the above response, it must be as easy as interchanging an airliner engine.

Do you know what it takes and how long to change out an airliner engine? 

https://blog.virginatlantic.com/change-aircraft-engine/

I saw a documentary on National Geographic it was too easy.

You'll notice they swap one engine, not an entire wing at once.

Tiles are the smart way of doing heat shields.

[spacexfanatic]

Please refere to the above response, it must be as easy as interchanging an airliner engine.

Do you know what it takes and how long to change out an airliner engine? 

https://blog.virginatlantic.com/change-aircraft-engine/

I saw a documentary on National Geographic it was too easy.

You'll notice they swap one engine, not an entire wing at once.

Tiles are the smart way of doing heat shields.

I was also suggesting swaping all the heat shield.

[rakaydos]

Please refere to the above response, it must be as easy as interchanging an airliner engine.

Do you know what it takes and how long to change out an airliner engine? 

https://blog.virginatlantic.com/change-aircraft-engine/

I saw a documentary on National Geographic it was too easy.

You'll notice they swap one engine, not an entire wing at once.

Tiles are the smart way of doing heat shields.

I was also suggesting swaping all the heat shield.

Why swap the whole heat shield if only a few tiles are damaged?

[spacexfanatic]

Please refere to the above response, it must be as easy as interchanging an airliner engine.

Do you know what it takes and how long to change out an airliner engine? 

https://blog.virginatlantic.com/change-aircraft-engine/

I saw a documentary on National Geographic it was too easy.

You'll notice they swap one engine, not an entire wing at once.

Tiles are the smart way of doing heat shields.

I was also suggesting swaping all the heat shield.

Why swap the whole heat shield if only a few tiles are damaged?

To make SS ready to fly as quickly as possible.

[rakaydos]

Please refere to the above response, it must be as easy as interchanging an airliner engine.

Do you know what it takes and how long to change out an airliner engine? 

https://blog.virginatlantic.com/change-aircraft-engine/

I saw a documentary on National Geographic it was too easy.

You'll notice they swap one engine, not an entire wing at once.

Tiles are the smart way of doing heat shields.

I was also suggesting swaping all the heat shield.

Why swap the whole heat shield if only a few tiles are damaged?

To make SS ready to fly as quickly as possible.

Swapping a 10 ton heat shield is going to be MUCH slower than scanning the shield, then swapping 4-5 tiles.

[sebk]

You guys find it easy to colonize Mars and hard to interchange a heatshield? if so I would prefer being more down to earth and let talk about how to put the american flag on the red planet soil before chinese do the same it's more interesting for me than the aspirationals goals (dreams) of EM.

Not just any heat shield, you want a single unitary heat shield, that is also swappable. While being made out of materials chosen for their thermal characteristics, not their durability.

There's a reason the shuttle used tiles, and starship is also using hexagonal tiles.

Those hexagonal tiles could be fixed to a structure that could be disassembled or fixed to SS, if you won't to operat quickly you won't be able to aford ideling all the spacecraft just because one tile has been damaged and need time to get repaired.

Such structure would be heavier than the tiles together.

But anyway, you got it backwards
Replacing one damaged tile is 15 minutes operation. They are "click on".

Replacing entire shield structure because of a single dent would take hours.

Better just replace the one tile.

10 tons for heatshield  any respectable overhead crane could manage such a weight.

it would be a sail so a building would be needed. And it'd be nearly as flexible as sail cloth. It'd need lots of hands and eyes to apply and verify it was installed properly.

Please refere to the above response, it must be as easy as interchanging an airliner engine.

Replacing airplane engine takes hours.