The beginnings of stealth technology

The work led by the Air Force Avionics Laboratory from the early 1950s to 1970s is discussed. Emphasis is placed on radar echo, although all observables-infrared radiation, optical, acoustics, etc.-are important to stealth design. The current capability to minimize observables is traced from the first efforts to understand what determines radar echo through the development of materials and techniques to minimize it. Applications and demonstrations are reviewed