Airborne Signals Intelligence SIGINT.

ELECTRONIC surveillance; FIGHTER planes; TURBOPROP airplanes; MILITARY intelligence; MILITARY technology

The article discusses that Signals intelligence (SIGINT) can be broken down into the interception and exploitation of communications signals between humans. It mentions that cold war SIGINT was often carried out using conversions or derivatives of large, multi-engine military transport aircraft or airliners; and also mentions that smaller aircraft and helicopters were sometimes used for tactical, battlefield SIGINT.