An ass landing is ANYTHING you can put your ass in or on. Especially important to know this term when you are under the influence.
Chairs, toilets, laps, penii/vag, bath tub, Face, floor, the ground, grass, table, etc.
"Where am I going?"
"We need to find somewhere to land our asses."
"I am finding no ass landings."
"Does my face look like a chair?"
"It seems to be a highly functional ass landing."