I think what Chimbu Chuckles is trying to say is on a bigger aircraft, with the main wheels behind the CoG a small change in attitude will produce a significant movement in the position of the main wheels.
In smaller aircraft, a 1 degree pitch change might move the wheels up and down by an inch or so, while on a larger aircraft this will be a number of feet.
This is all due to the distance from the CoG to the main wheels.
Bevan..