The upper wing can make the fuselage close to the ground, which is beneficial to loading and unloading goods and has poor sliding stability, so it is often used in military transport aircraft. The aerodynamic dry resistance of the middle wing is the smallest, and it is mostly used in fighter planes. The lower wing can protect the fuselage in an emergency landing, and it can make the fuselage emerge from the water when it is forced to land on the water, which is conducive to evacuating passengers, so it is often used in passenger planes.
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The engineering team led by NASA has developed a new type of aircraft wing, which is assembled by a large number of triangular brackets and other components, and can be deformed according to flight conditions to meet the requirements of wing shape in different flight stages. It is reported that this wing has completed the wind tunnel test.
Recently, a research paper published in the British magazine "Intelligent Materials and Structures" said that this kind of wing is composed of thousands of triangular brackets and other components, forming a hollow lightweight structure with a weight of only 5.6 kilograms per cubic meter, which is lighter and more energy-saving than the traditional wing.
This new type of wing is about 5 meters long, which is equivalent to the wing of a single-seat aircraft. The position of the assembly is carefully designed, so that the wing or a part of the wing can bend in a specific way under different stresses. This wing has been tested in the high-speed wind tunnel of NASA Langley Research Center, and its performance is good.