Anybody who has flown a parachute dropping aircraft will have found out all about operating at the extremes of the C of G envelope. On takeoff with all the human ballast in the back, it's on the rear cg limit, elevator very sensitive and easy to lift the nose wheel. When they all depart in a bunch, suddenly a lot of nose up trim required as it is now on the forward CG limit and on landing with full nose up trim, it takes a big heave to touch on the main wheels.