The Boeing RC-135 is a large family of reconnaissance aircraft used by the United States Air Force to support theater and national level intelligence consumers with near real-time on-scene collection, analysis and dissemination capabilities. Based on the C-135 Stratolifter airframe, various types of RC-135s have been in service since 1961. Many variants have been modified numerous times, resulting in a large variety of designations, configurations, and program names.
The aircraft is an extensively modified C-135 with on-board sensors which enable the crew to detect, identify and geolocate signals throughout the electromagnetic spectrum. The crew can then forward information in a variety of formats to a wide range of consumers via the onboard secure communications suite.
In 2005, the RC-135 fleet completed a series of significant airframe, navigational and power-plant upgrades which include re-engining from the Pratt & Whitney TF-33 to the CFM International CFM-56 (F-108) engines used on the KC-135R and T Stratotanker and upgrade of the flight deck instrumentation and navigational systems to the AMP standard. The AMP standard includes conversion from analog readouts to a digital "glass cockpit" configuration.
The current RC-135 fleet is the latest iteration of modifications to this pool of aircraft going back to the early 1960s. Initially employed by Strategic Air Command for reconnaissance, the RC-135 fleet has also participated in every armed conflict involving U.S. assets during its tenure. RC-135s supported operations in Vietnam, the Mediterranean for Operation El Dorado Canyon, Grenada for Operation Urgent Fury, Panama for Operation Just Cause, the Balkans for Operations Deliberate Force and Allied Force, and Southwest Asia for Operations Desert Shield, Desert Storm, Enduring Freedom and Iraqi Freedom. RC-135s have maintained a constant presence in Southwest Asia since the early 1990s.