(a) in the direction of the airplane's landing

The airplane will touch down, and the tires will not spin.

(b) in the opposite direction of the airplane's landing

The airplane will touch down as before, and the tires will spin twice as
fast as they would have landing on still ground.

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
for Email, make the obvious change in the address.