How fast does the skin of the airplane cool to surrounding temperatures?

Mxsmanic wrote:
Peter R. writes:

A question for those of you more adept at chemistry/physics than I: How
fast does the aluminum skin of the standard single engine GA aircraft take
to cool to surrounding air temperatures? For example, how long would it
take for the skin to cool from a heated hangar at 65 degrees F to outside
air at 20 degrees F?

On a clear night the skin temperature can go BELOW the air
temperature due to the radiation losses into space. We regularly see
that here, and it's what causes frost to form so quickly.

Dan