Monoplane

A monoplane is a type of fixed-wing aircraft that has just one main set of wings. This is different from a biplane or other multiplanes, which have two or more sets of wings. Monoplanes are special because they are usually the most efficient and have the least resistance when flying through the air. They are also the simplest kind of winged airplane to build.

In the early days of flying, monoplanes were not used very often. This was because they were heavier and could not turn as easily as other planes. But after the 1930s, monoplanes became the most common kind of airplane. Today, almost all airplanes you see in the sky are monoplanes because they work so well. You can find them in many shapes, like the low wing of a Supermarine Spitfire, the mid wing of a de Havilland Vampire T11, the high wing of a de Havilland Canada Dash 8, or the parasol wing on R.J. Mitchell's 1930 Supermarine Air Yacht.

Characteristics

The monoplane is very efficient because it has just one wing. The best kind of monoplane wing is called a "cantilever," which means it carries all its weight inside itself. But to fly well, the wing needs to be thin, which makes it heavier and harder to build.

Early monoplanes often had extra supports called "bracing" outside the wing. This made them lighter and cheaper, and let them fly slower with smaller engines. But these supports also made the plane slower because they created drag. Today, planes that need to go fast and far usually don’t have these supports, while slower, shorter-distance planes might still use them.

Wing position

Besides different ways to arrange the wings, the main difference in monoplanes is where the wing is placed up and down on the body of the plane, called the fuselage.

Low

A low wing is placed on or near the bottom of the fuselage.
This helps the pilot see upward better and keeps the middle part of the fuselage open. It can make the plane easier to turn, like on the Spitfire; but planes that need to stay steady may need extra help to stay balanced.

Mid

A mid wing is placed in the middle of the fuselage. This is the most common shape for big planes, especially those that carry passengers.

Shoulder

A shoulder wing sits near the top of the fuselage but not all the way up. This helps the plane stay steady and gives more space for the wheels of the plane. On smaller planes, this shape lets the pilot see better. Examples include the ARV Super2, the Bölkow Junior, Saab Safari and the Barber Snark.

High

A high wing sits on or above the top of the fuselage. On small planes such as the Cessna 152, the wing is usually above the seats, which helps load things easier. Many military planes that carry cargo have this shape.

Parasol

A parasol wing is not stuck directly to the fuselage but held above it, using special supports. This was useful for old fighting planes like the Fokker D.VIII and for water planes that needed to keep their propellers away from spray, like the Martin M-130, Dornier Do 18 and the Consolidated PBY Catalina. This shape is still used for small planes people build themselves.

History

The very first attempts to build airplanes were monoplanes, even though the first successful airplanes were biplanes. Early examples include the 1907 Santos-Dumont Demoiselle, which was the first airplane made for production, and the Blériot XI, which flew across the English Channel in 1909. During 1909–1910, Hubert Latham set many height records in his Antoinette IV monoplane, reaching as high as 1,384 meters (4,541 feet).

In Germany, monoplanes were called Eindecker. A famous example was the mid-wing Fokker Eindecker fighter from 1915, which for a short time was very successful. However, World War I was mostly fought with biplanes. By the end of the war, the parasol monoplane became popular, and many successful designs were made in the 1920s.

Few monoplanes were built between 1914 and the late 1920s because early engines were not strong enough. Monoplanes needed large wings to stay in the air, while biplanes could have two smaller wings and be lighter. As engines became stronger, all-metal construction and the cantilever wing made monoplanes more practical. By the 1930s, the cantilever monoplane became the standard design for airplanes. Advanced monoplane fighter planes were made in the Soviet Union and the United States during the early to mid 1930s, such as the Polikarpov I-16 and the Boeing P-26 Peashooter.

Most military aircraft in WWII were monoplanes, and nearly all airplanes since then have been monoplanes. With the even greater power of jet and rocket engines, all modern high-speed airplanes, especially those that can go faster than the speed of sound, are monoplanes.