My great aunt used to be a Wing Walker.
Back in the 20-30’s, that was a featured part of Airplane Expositions.
Ladies would get out of the back seat of old biplanes once they got off the ground and crawl up on top of the upper wing, dance around (at maybe 60 or 70 mph) and do all sorts of crazy stuff....
Ol’ Aunty was a certified nutcase, anyway......
Wing walkers had ropes or some such holding them against the wind current, IIRC.