Stealth Aircraft

Stealth Aircraft, military aircraft, fighters, and bombers designed to elude detection and tracking systems, such as radar and infrared monitoring (see Airplane: Military Airplanes). Stealth technology is also used to mask unmanned objects such as cruise missiles (see Guided Missiles: Tactical Missiles) and some unmanned aerial vehicles. The United States is a world leader in developing and deploying stealth technology, although much about its program remains classified.

Stealth technology includes a variety of design features that affect an aircraft’s signal, also called its signature, on tracking systems. These features include an aircraft’s shape and the materials used to build it. For example, it is harder for a radar to detect an aircraft that has smooth, rounded curves. Special composite materials or coatings on the surface of an aircraft can absorb or deflect radar signals. Engines placed within the body of the aircraft and exhaust vents may be arranged to mask the heat emitted from engines and help hide an aircraft from heat-seeking infrared sensors. Reducing the noise and vibration produced by a stealth aircraft may also minimize its acoustic signature. In addition, stealth aircraft are equipped with special electronics for suppressing or confusing enemy monitoring systems.

Since the use of radar during World War II (1939-1945), air forces worldwide have tried to develop methods of confusing radar or making it ineffective. Early attempts at this included the targeted aircraft attempting to electronically jam radar or to release metallic strips to produce false readings. However, in the 1950s and 1960s, new electronic tracking methods and the new ways devised to confuse them kept pace with one another, prompting military engineers to look for ways to completely mask aircraft.

American aeronautical engineer Clarence L. “Kelly” Johnson was instrumental in the design and development of stealth aircraft. In the mid-1950s, Johnson and his colleagues at Lockheed Aircraft Corporation designed the U2, an aircraft with a slim profile and radar-absorbing black paint that helped reduce its signature. Johnson was also the developer of the SR-71, the successor of the U2, which used a radar-absorbent polymer coating on its wings.

During the 1970s and 1980s, the U.S. government and military contractors began designing and building stealth aircraft from the ground up, rather than merely giving existing aircraft stealth characteristics. Although the U.S. government acknowledged the existence of a stealth aircraft program in 1980, America's first two stealth aircraft were not revealed to the press until 1988.

Lockheed developed the F-117A Nighthawk fighter, which was deployed during the United States invasion of Panama in 1989, the Persian Gulf War in 1991, and the U.S.-Iraq War in 2003. The F-117A was retired in 2008. The B-2 Spirit stealth bomber was developed by the Northrop Grumman Corporation and has seen combat in Kosovo, in Afghanistan, and in Iraq. New military aircraft such as the F-22 Raptor fighter and the F-35 Lightning II—formerly called the Joint Strike Fighter (JSF)—incorporate more advanced stealth design and technology.