 Particularly on larger or faster aircraft, control forces may be extremely heavy.Borrowing a discovery from boats that extending a control surface's area forward of the hinge lightens the forces needed first appeared on ailerons during World War I when ailerons were extended beyond the wingtip and provided with a horn ahead of the hinge.Known as overhung ailerons, possibly the best known examples are the Fokker Dr.I and Fokker D.VII.