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11 minutes ago, pmborg said:

Yes true 133 client satelites plus 10 starlinks

A lot of sats to be sure, but way smaller than the starlinks (a bunch of volume used for the dispensers).

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Mildly off-topic -- my ex moved our kids to a house without internet service (long story lol) so I promptly ordered Starlink for them.  It says they are targeting mid to late 2021 for this service area (rural Virginia) which I believe ought to be now.

Has anyone else used Starlink or does anyone else have an idea of what the turnaround time is like?

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39 minutes ago, CatastrophicFailure said:

I think that's supposed to be headER tank...

 

 

 

Gotta love the COVID warning on the second tweet. 


What would be the drag impact on ascent of scales vs. tiles? I’d guess scales would be a good bit more turbulent…

Edited by GearsNSuch
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2 hours ago, GearsNSuch said:


What would be the drag impact on ascent of scales vs. tiles? I’d guess scales would be a good bit more turbulent

I'm interested in this as well - but I would think that a correct shape of scale would be less turbulent (c.f. Fish & Sharks). 

Speedo invented (a now banned) swimwear line for competitive swimmers which dramatically reduced drag, including features that mimicked the dermal denticles (scale like structures) found on sharks. 

While hexes are simple and break up the flow of plasma effectively - scale structures could improve or reduce drag and provide similar plasma protection 

https://news.harvard.edu/gazette/story/2018/02/in-aerodynamic-performance-sharkskin-model-offers-more-lift-less-drag/

 

Edited by JoeSchmuckatelli
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6 minutes ago, JoeSchmuckatelli said:

I'm interested in this as well - but I would think that a correct shape of scale would be less turbulent (c.f. Fish & Sharks). 

Speedo invented (a now banned) swimwear line for competitive swimmers which dramatically reduced drag, including features that mimicked the dermal denticles (scale like structures) found on sharks. 

While hexes are simple and break up the flow of plasma effectively - scale structures could improve or reduce drag and provide similar plasma protection 

 

Fish don't swim at hypersonic speed, though. It might be a different challenge.

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5 minutes ago, cubinator said:

Fish don't swim at hypersonic speed, though. It might be a different challenge

Sounds like a good time to engage @mikegarrison-whether standard plane skin / shape must be modified for supersonic / hypersonic flight. 

Of particular interest is the Harvard researchers' discovery that not only do the shapes improve drag, they increase lift. 

I know overall craft shape has been modified to enable supersonic flight - but has anyone looked at whether a modified skin is beneficial for super/hyper-sonic flight? 

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14 minutes ago, JoeSchmuckatelli said:

Sounds like a good time to engage @mikegarrison-whether standard plane skin / shape must be modified for supersonic / hypersonic flight. 

Of particular interest is the Harvard researchers' discovery that not only do the shapes improve drag, they increase lift. 

I know overall craft shape has been modified to enable supersonic flight - but has anyone looked at whether a modified skin is beneficial for super/hyper-sonic flight? 

I discussed this before, in the Airplane Q&A thread. The word you want to search on is "riblets", although Airbus does like to call it "shark skin".

 

 

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44 minutes ago, JoeSchmuckatelli said:

While hexes are simple and break up the flow of plasma effectively - scale structures could improve or reduce drag and provide similar plasma protection 

Air drag gets a lot of conversational real estate in this thread, but keep in mind, it’s a bit of a lesser concern vs airplanes. After the first couple of minutes of flight it ceases to be a concern at all, really. A rocket only needs to be aerodynamic enough, obsessing over minimizing every tiny bit of drag loss quickly becomes a diminishing return. If you’ve ever seen a closeup of the shuttle ET, or even an Atlas V, the surface is extremely rough from the insulation. Making it less so just isn’t worth it in the grand scheme since it’s a trivial loss vs the mass penalty (among other things) of making the skin perfectly smooth. I reckon it’s a similar deal with Starship, the tiles are aerodynamically good enough. At least for now. 
 

13 minutes ago, mikegarrison said:

The word you want to search on is "riblets",

Mmmmmmm, riblets

simpsons-dreamy.gif

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19 minutes ago, mikegarrison said:

riblets

'Easy to damage, hard to maintain' 

And 

7 minutes ago, CatastrophicFailure said:

After the first couple of minutes of flight it ceases to be a concern at all, really. A rocket only needs to be aerodynamic enough,

... Are the perfect answers. 

 

Thanks fellers! 

Edit - back to the question of hexes vs scales for reentry plasma - is there anything to add besides 'they just need to be good enough' and 'unnecessarily complicated /expensive for the comparable benefits'? 

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I think the thermal expansion potential of the a scale like design could be useful. Def more intuitive space for expansion without gaps, but maybe the sliding forces could cause scratches? Might be hard to tell if they were underneath the other tiles too, and lead to needing costly inspections. Is the expansion of the tiles even a concern? Do we know the coefficent of whatever material they are using?

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15 hours ago, CatastrophicFailure said:

I think that's supposed to be headER tank...

 

 

 

The overlapping tiles works well for tiled roofs, it was an pretty common type of medieval armor and fish and many plant use it. However it tend to require pretty thin tiles, yes not so much for tiled roofs but they only need to be watertight from  rain who tend to come from above. 

Now Musk responding to Everyday astronaut is awesome. Now metal is way stronger but can not handle the heat of ceramic. 

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