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Would a rotating skin design - where the skin of the aircraft rotates (powered either by an electric motor or the colluding wind) - mitigate the heating problem limiting hypersonic flight?

Would a liquid cooling system (to cool the skin as it rotates along the aircraft) add additional benefit?

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    $\begingroup$ I think I see where you're heading. By moving the skin, you're taking a piece of skin away from the highest heat spot and allowing it to cool before eventually moving it back into the blast furnace of the leading edges. However, I would imagine that the mechanisms to make the skin crawl :) would be far more complex than most of the rest of the aircraft. Additionally, modern aircraft design uses the skin itself as a stressed member - detaching it from the underlying structure would, essentially, cause the structure to fail. $\endgroup$ – FreeMan Jan 17 '18 at 19:30
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    $\begingroup$ A liquid cooling system worked for the SR-71 without rotating the skin. Fuel was piped through capillaries in the skin for the dual purpose of cooling the skin and heating the fuel $\endgroup$ – TomMcW Jan 17 '18 at 21:50
  • $\begingroup$ related, if not duplicate: aviation.stackexchange.com/q/44600/1467 $\endgroup$ – Federico Jan 18 '18 at 13:46
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TL;DR Probably not.

Assuming we would have a very good mechanical solution/design we would still need a way to get rid of the heat, i.e. a heat-sink.

Imagine the panel (or what ever we will call a part of the skin) is rotated away from the flow (into the inside of the vehicle), than we would need to cool it but where would we store the heat? We cannot extend a heat-exchanger. So the inside of the vehicle would heat up indefinitely.

Essentially we need to come up with a way to discharge entropy from the vehicle. This can be done by either a heat- or mass-flux from the vehicle into the ambiance.

One possibility is related to your second idea: using a cooling system. This requires you to have a fluid propellant. Using the fluid propellant as a cooling fluid first you would not only cool your airframe but you would also enhance your efficiency. This also solves the heat/entropy problem because you would discharge mass (the propellant).

But given the fact that we assumed to have a matured mechanical design of the ‚skin-rotation‘ mechanism you could have multiple panels with ablative coating. So after the first panel is consumed you could (hypothetically) rotate a new one into the flow.

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