 Between the wars in Europe, the Nieuport-Delage NiD 42/52/62 series, Fokker C.Vd & e, and Potez 25 sesquiplanes served in many air forces, while the Waco Custom Cabin series proved to be a popular general aviation aircraft.The Saro Windhover was a sesquiplane with the upper wing smaller than the lower, a much rarer configuration than the reverse.Stacking of wing planes was suggested by Sir George Cayley in 1843.