Biplane

biplane is an airplane with two sets of wings, one above the other. The biplane was developed from the box kite, which was invented by an Australian named Lawrence Hargrave in 1893.

Before the days of powered flight, aviation pioneers, such as Otto Lilienthal in Germany and Octave Chanute in the United States, flew biplane hang gliders. They experimented with how to control an aircraft carrying a human pilot with no engine. The first controlled powered flight, in 1903, was made by a biplane, the Wright brothers’ Flyer. The first powered flight in Europe was also made by a biplane, this time flown by a Brazilian pilot called Alberto Santos – Dumont, in 1906.

One Wing or Two?

In the early years of airplane develop­ment, engineers were not sure which design flew best: the monoplane (with one wing) or the biplane (with two wings). They tried adding more wings to see if this worked. In 1908 the first tri­plane (with three wings) took to the air, but triplanes never became widespread.

The biplane appeared to fly more steadily than the monoplane. Engineers believed this was because two wings gave more lift than one wing. In fact, a disadvantage of the biplane is that the two sets of wings tend to interfere with one another, thereby reducing lift and increasing drag.

Overall, early wing designs were not very efficient. There was little difference between the performance of monoplanes and biplanes in the days of low-power engines and slow speeds. Biplanes were stronger than monoplanes, however— their wings were braced by taut wires and wooden struts. This was important in the early days, before 1930, when most airplanes were flimsy structures of wood and cloth. The wings were an air­plane’s weakest point, and it was not unusual for the wings to fall off when a plane was diving or turning, usually with fatal consequences for the pilot.

To improve lift and reduce drag, biplane designers tried “staggering” the wings. This usually meant fixing the upper wing slightly in front of the lower wing, but there were also biplanes that had the lower wing set farther forward. Staggering worked quite well, and biplanes proved as useful as monoplanes for some time.