The Boeing RC-135 is a family of large reconnaissance aircraft built by Boeing and modified by a number of companies, including General Dynamics, Lockheed, LTV, E-Systems, and L3 Technologies, and used by the United States Air Force and Royal Air Force to support theater and national level intelligence consumers with near real-time on-scene collection, analysis and dissemination capabilities.

A reconnaissance aircraft is a military aircraft designed or adapted to perform aerial reconnaissance with roles including collection of imagery intelligence, signals intelligence, as well as measurement and signature intelligence. Modern technology has also enabled some aircraft and UAVs to carry out real-time surveillance in addition to general intelligence gathering.