August 12, 2016:
In mid-2016 Argentina revealed that it had completed converting an eight ton Learjet 35A business jet into an ELINT (electronic intelligence)) aircraft. The twin jet Learjet was now an ELINT aircraft and replaces a 15o ton Boeing 707 aircraft Argentina had sent to Israel in 1986 for conversion to an ELINT aircraft. The conversion was carried out by European military electronics manufacturer Thales. The smaller business jets can handle these jobs because since the 1980s the size, weight and cost of the required electronics has shrunk enormously. The software required to operate all this gear is a lot more efficient and fewer people are needed on an ELINT aircraft to make it work. In fact, the next generation ELINT aircraft will be a UAV operating robotically or via human operators on the ground.
Since 2000 a growing number of nations have been using business jets for electronic warfare and aerial surveillance and air control. For example since 2009 the U.S. Air Force has used specially equipped Learjet 35 aircraft for electronic warfare training.