At one point in Red Dwarf: Back to Earth, Rimmer claims water came
rushing down on him at “80 knots per hour”.
This is probably just to show Rimmer’s lack of intelligence, but
“knots” is a measure of velocity (1 nautical mile per hour), not
Thus, 80 knots per hour is a measure of acceleration, and equates to
about 1/1000th of a g, which is probably not even noticeable.
Rimmer of course probably meant to say the water was coming down at 80
knots, which translates to 92mph, a fairly decent speed.