Biplane
The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation.
Improved structural techniques, better materials and higher speeds made the biplane configuration obsolete for most purposes by the late 1930s.
Rigging wires on non-cantilevered monoplanes are at a much sharper angle, thus providing less tension to ensure stiffness of the outer wing.
On a biplane, since the angles are closer to the ideal of being in direct line with the forces being opposed, the overall structure can then be made stiffer.
As engine power and speeds rose late in World War I, thick cantilever wings with inherently lower drag and higher wing loading became practical, which in turn made monoplanes more attractive as it helped solve the structural problems associated with monoplanes, but offered little improvement for biplanes.
Common examples include the de Havilland Tiger Moth, Bücker Bü 131 Jungmann and Travel Air 2000.
Indeed many early aircraft relied on the fabric covering of the wing to provide this rigidity, until higher speeds and forces made this inadequate.
[16] The Albatros D.III and D.V, which had also copied the general layout from Nieuport, similarly provided the backbone of the German forces during the First World War.
[18] During interwar period, the sesquiplane configuration continued to be popular, with numerous types such as the Nieuport-Delage NiD 42/52/62 series, Fokker C.Vd & e, and Potez 25, all serving across a large number of air forces.
[21] Hiram Maxim adopted the idea for his steam-powered test rig, which lifted off but was held down by safety rails, in 1894.
Figures such as aviation author Bruce observed that there was an apparent prejudice held even against newly-designed monoplanes, such as the Bristol M.1, that caused even those with relatively high performance attributes to be overlooked in favour of 'orthodox' biplanes, and there was an allegedly widespread belief held at that time that monoplane aircraft were inherently unsafe during combat.
[29] The French were also introducing the Morane-Saulnier AI, a strut-braced parasol monoplane, although the type was quickly relegated to the advanced trainer role following the resolution of structural issues.
The British de Havilland Dragon was a particularly successful aircraft, using straightforward design to could carry six passengers on busy routes, such as London-Paris services.
The 1917 Junkers J.I sesquiplane utilized corrugated aluminum for all flying surfaces, with a minimum of struts; however, it was relatively easy to damage the thin metal skin and required careful handling by ground crews.
[35] The 1918 Zeppelin-Lindau D.I fighter was an all-metal stressed-skin monocoque fully cantilevered biplane, but its arrival had come too late to see combat use in the conflict.
The British Gloster Gladiator biplane, the Italian Fiat CR.42 Falco and Soviet I-153 sesquiplane fighters were all still operational after 1939.
[36][37] According to aviation author Gianni Cattaneo, the CR.42 was able to achieve success in the defensive night fighter role against RAF bombers that were striking industrial targets throughout northern Italy.
Its low stall speed and inherently tough design made it ideal for operations even in the often severe mid-Atlantic weather conditions.
[40] By the end of the conflict, the Swordfish held the distinction of having caused the destruction of a greater tonnage of Axis shipping than any other Allied aircraft.
[41] Both the German Heinkel He 50 and the Soviet Polikarpov Po-2 were used with relative success in the night ground attack role throughout the Second World War.
[43] The Po-2 is also the only biplane to be credited with a documented jet-kill, as one Lockheed F-94 Starfire was lost while slowing down to 161 km/h (100 mph) – below its stall speed – during an intercept in order to engage the low flying Po-2.
The Stearman PT-13 was widely used by the United States Army Air Force (USAAF) while the US Navy operated the Naval Aircraft Factory N3N.
In later civilian use in the US, the Stearman became particularly associated with stunt flying such as wing-walking, and with crop dusting, where its compactness worked well at low levels, where it had to dodge obstacles.
The feathered dinosaur Microraptor gui glided, and perhaps even flew, on four wings, which may have been configured in a staggered sesquiplane arrangement.
