like thousands of rear gunners I discovered that the tail constantly wags from side to side;
Years ago in Hong Kong I bagged a ride in a Cathay aircraft as an observer on a crew training sortie. This was in the days when you actually had to fly an aeroplane to get a rating. During the flight the training captain told us all to go right down the back and see what happens. He then fishtailed the aircraft to demonstrate to his new pilots what it feels like down the back if you are hamfooted with the rudder. It was quite unnerving be pushed about three feet one way to the other.
Later I was flying into Hong Kong when Kai Tak was still in use. My tight fisted company had me down the back in cattle class and being a smoker I was in the last row. The 747 did the normal starboard wingtip festooned with TV ariels approach but had to much drift on final touchdown.
He booted the aircraft straight and the effect in the back was seriously disconcerting for me but terrifying for my fellow passengers. They were screaming and crying all the way down the landing roll. There was a bit of an apology on the PA and the hosties did their best but it was not a pleasant experience.