Four-engine turboprop signals intelligence (SIGINT) reconnaissance aircraft.
During the 1990s twelve P-3Cs were converted to EP3-E ARIES II to replace older versions of the aircraft. The original ARIES I aircraft were converted in the late 1960s and early 1970s. The last EP-3E ARIES II aircraft was delivered in 1997. EP-3Es have been heavily engaged in reconnaissance in support of NATO forces in Bosnia, joint forces in Korea and in Operation Southern Watch, Northern Watch, and Allied Force.
The EP-3E ARIES II (Airborne Reconnaissance Integrated Electronic System II) is the Navy's only land-based signals intelligence (SIGINT) reconnaissance aircraft. The 11 aircraft in the Navy's inventory are based on the P-3 Orion airframe and provide fleet and theater commanders worldwide with near real-time tactical SIGINT. With sensitive receivers and high-gain dish antennas, the EP-3E exploits a wide range of electronic emissions from deep within targeted territory.