George Patterson writes:

The two approaches I've read about are 1) Have the wings and empennage attach
to the car. The car lands, unhooks the assembly, and leaves it at the airport.
2) Use detachable and folding wings and tailfeathers and trailer them. The EAA
museum at Oshkosh has one of these on display.

A (Lotus) concept car for #1 was on display at Oshkosh a couple years ago.

--kyler