The trapezoid

Trapezoid

In Euclidean geometry, a convex quadrilateral with one pair of parallel sides is referred to as a trapezoid in American English and as a trapezium in English outside North America. A trapezoid with vertices ABCD is denoted...

al or diamond wing is a high-performance wing configuration

Wing configuration

Fixed-wing aircraft, popularly called aeroplanes, airplanes or just planes may be built with many wing configurations.This page provides a breakdown of types, allowing a full description of any aircraft's wing configuration...

. It is a short (low aspect ratio) tapered wing having little or no overall sweep

Swept wing

A swept wing is a wing planform favored for high subsonic jet speeds first investigated by Germany during the Second World War. Since the introduction of the MiG-15 and North American F-86 which demonstrated a decisive superiority over the slower first generation of straight-wing jet fighters...

, such that the leading edge

Leading edge

The leading edge is the part of the wing that first contacts the air; alternatively it is the foremost edge of an airfoil section. The first is an aerodynamic definition, the second a structural one....

 sweeps back and the trailing edge

Trailing edge

The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge rejoins. Essential control surfaces are attached here to redirect the air flow and exert a controlling force by changing its momentum...

 sweeps forwards. The trapezoidal design allows for a thin wing with low drag at high speeds, while maintaining high strength and stiffness. To date, all major aircraft to use this design have come from the United States.

History

Early examples provided a solution to the problem of supersonic flight when engine power was limited. The wing of the Douglas X-3 Stiletto

X-3 Stiletto

The Douglas X-3 Stiletto was a 1950s United States experimental jet aircraft with a slender fuselage and a long tapered nose, manufactured by the Douglas Aircraft Company. Its primary mission was to investigate the design features of an aircraft suitable for sustained supersonic speeds, which...

 was extremely small and thin, giving low drag at supersonic speeds. The principle was adopted for various other X-plane

X-plane

The X-planes are a series of experimental United States airplanes and helicopters used for the testing and evaluation of new technologies and aerodynamic concepts...

s and for Lockheed's widely-produced F-104 Starfighter

F-104 Starfighter

The Lockheed F-104 Starfighter is a single-engine, high-performance, supersonic interceptor aircraft originally developed for the United States Air Force by Lockheed. One of the Century Series of aircraft, it served with the USAF from 1958 until 1969, and continued with Air National Guard units...

 high-speed, high-altitude interceptor. Lockheed used the design on many of its aircraft proposals in the 1950s, including the Lockheed CL-400 Suntan and early versions of their supersonic transport

Supersonic transport

A supersonic transport is a civilian supersonic aircraft designed to transport passengers at speeds greater than the speed of sound. The only SSTs to see regular service to date have been Concorde and the Tupolev Tu-144. The last passenger flight of the Tu-144 was in June 1978 with its last ever...

 designs.

The small wing of the Starfighter was found to have good gust response at low level, providing a smooth ride at high subsonic speeds. Consequently the type was adopted for the ground-attack role, notably by the German Luftwaffe

Luftwaffe

Luftwaffe is a generic German term for an air force. It is also the official name for two of the four historic German air forces, the Wehrmacht air arm founded in 1935 and disbanded in 1946; and the current Bundeswehr air arm founded in 1956....

. However the small size of the wing also meant high take-off and landing speeds with minimal stability or control, and many pilots were killed during takeoff and landing accidents.

More recently, a larger and less highly loaded variant has been found to provide good all-round speed, load carrying and maneuvering characteristics for modern combat fighters such as the Lockheed F-22 Raptor and others. Its inherent light weight has also led to its adoption for the VTOL

VTOL

A vertical take-off and landing aircraft is one that can hover, take off and land vertically. This classification includes fixed-wing aircraft as well as helicopters and other aircraft with powered rotors, such as cyclogyros/cyclocopters and tiltrotors...

-capable F-35 Lightning II

F-35 Lightning II

The Lockheed Martin F-35 Lightning II is a family of single-seat, single-engine, fifth generation multirole fighters under development to perform ground attack, reconnaissance, and air defense missions with stealth capability...

 Joint Strike Fighter.

X-plane

X-plane

The X-planes are a series of experimental United States airplanes and helicopters used for the testing and evaluation of new technologies and aerodynamic concepts...

s

• X-3 Stiletto
  X-3 Stiletto
  The Douglas X-3 Stiletto was a 1950s United States experimental jet aircraft with a slender fuselage and a long tapered nose, manufactured by the Douglas Aircraft Company. Its primary mission was to investigate the design features of an aircraft suitable for sustained supersonic speeds, which...
  
  
• Lockheed X-7
  Lockheed X-7
  -See also:-External links:*...
  
  
• North American X-15
  North American X-15
  The North American X-15 rocket-powered aircraft/spaceplane was part of the X-series of experimental aircraft, initiated with the Bell X-1, that were made for the USAAF/USAF, NACA/NASA, and the USN. The X-15 set speed and altitude records in the early 1960s, reaching the edge of outer space and...
  
  
• Lockheed X-27

Military planes

• F-104 Starfighter
  F-104 Starfighter
  The Lockheed F-104 Starfighter is a single-engine, high-performance, supersonic interceptor aircraft originally developed for the United States Air Force by Lockheed. One of the Century Series of aircraft, it served with the USAF from 1958 until 1969, and continued with Air National Guard units...
  
  
• Lockheed F-22 Raptor
• Northrop YF-23
• F-35 Lightning II
  F-35 Lightning II
  The Lockheed Martin F-35 Lightning II is a family of single-seat, single-engine, fifth generation multirole fighters under development to perform ground attack, reconnaissance, and air defense missions with stealth capability...
  
  
• YF-22
  YF-22
  The Lockheed/Boeing/General Dynamics YF-22 was a single-seat, twin-engined prototype fighter aircraft designed for the United States Air Force . The YF-22 was a finalist in the USAF's Advanced Tactical Fighter competition; two prototypes were built. The YF-22 won the contest against the Northrop...