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8 minutes ago, coyotesfrontier said:

For most aircraft that might be a problem, but rockets are a different story :wink:

True, something built to hold cryogenic liquids should probably be fine. Even icing on the control surfaces shouldn't be a huge deal since they're more like spoilers. I think that the only risk would be buildup of ice on the joints such that the control surfaces are unable to actuate (if they were crazy enough to try and fly in such conditions).

Edited by Silavite
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The main problems with ice on airplanes is that it ruins the aerodynamic shaping of the surfaces and is heavy. Rockets are certainly susceptible to at least the latter issue.

I might also point out that the shuttle losses were caused by (or at least partially caused by):

a) cold weather, and

b) ice buildup on the tank insulation.

For what that's worth.

Edited by mikegarrison
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20 minutes ago, mikegarrison said:

The main problems with ice on airplanes is that it ruins the aerodynamic shaping of the surfaces and is heavy. Rockets are certainly susceptible to at least the latter issue.

I might also point out that the shuttle losses were caused by (or at least partially caused by):

a) cold weather, and

b) ice buildup on the tank insulation.

For what that's worth.

Now one problem with starship might be water behind the tiles if it freezes and expand. 

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On 2/13/2021 at 7:41 AM, tater said:

 

 

Did i hear 30Tons header tank (Lox) ? i'm surprised : (or is it 13T ?)

- they only need 11T total to desorbit and land safely, why would they put so much fuel in the top ?

- the only reason i see is to have more weight in the top, that gives a better balance during atmo reentry, this explains why they need bigger flaps at the top compared to my simulations. It also gives more margin for fueled trajectory correction.

- previoulsly i extrapolated the header tank volume and weight from photos, and ended with a 25-30m3 ->20-25T Lox, i thought it was too much, but why not.

- It could also explain why the terminal velocity seems to be around 87m/s : i found 76 m/s with 10T remaining fuel. With 35T remaining fuel Starship probably ends at 85-90 m/s.

 

I'm curious about this, i will have to retest Starship reentry, will 25T added fuel for landing increases the temperatures ? (Starship 116T vs 141T)

 

Edited by xebx
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23 hours ago, CastleKSide said:

@xebx what kind of system are you using for these simulations? Custom programming or some kind of flight sim?

KSP RSSRO (and Principia), procedural tank has a setting "tank-sep-starship" (stir-welded), add to this Raptors (small tweaks : SL 108% = 1921kN, Vac 105% = 2055kN) and procedural fairing (density 0.12), and the result is very close to/can be crossed with known data (wikipedia, etc).

There are some limitations (for ex : small wings are not flaps) and possible inaccuracies,  but so far it looks fine.

Edited by xebx
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Just now, sevenperforce said:

We’ve...

...got...

...a...

SUPERHEAVY GRIDDDDD FINNNNNN!!!!!!!!

 


 

Exciting. Do you think this will go on BN1, or is it just in Boca Chica for mounting checks/storage?

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That grid fin is what, ~7x12 ft? (pallets on lift, std pallet is 48x40 inches)

A 3x5 square bit fits as a large rectangle within the look of the previous renders. Will need more sections, then an outer line.

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^^^that's sorta what I was getting at before. I put it at a different part of the SH render where  a 3x5 "squares" rectangle fits within that render's gridfin. You can look at the image neopork did and find a 3x5 section.

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1 hour ago, magnemoe said:

Now why split it for transport as it would fit on an truck anyway and smarter to make it at an factory? 

The factory making giant rockets isn't good enough?

It was only moving "inside" the factory, after all.

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