4. Focus on the Lockheed F117

Table 3 summarizes the F117 specifications.

A product of the 1970s "Skunk Works" research program, the Have Blue prototype gave birth to the F117, which flew for the first time in June 1981. The aluminum and titanium structure is entirely coated with absorbent material, made from a polymer filled with ferrous particles. This material, initially applied in glued sheets, was then sprayed onto the aircraft, which was turned like a chicken in a rotisserie.

The aircraft's structures also make extensive use of NIDA composites which, if not loaded with iron, allow the radar wave to pass through almost unaltered (provided there are no obstacles inside, such as cables or pipes). Wing leading edges, vertical fins and trailing edges are made of structural composites filled with radar absorbers....