The EA-6B Prowler was developed to match the U.S Navy’s defenses in today’s electronic warfare environment. The first EA-6B was received by the Navy at NAS Whidbey Island, Washington in January 1971 and deployed to Vietnam in 1972. This "standard version" of the aircraft was replaced in 1973 with the "expanded capability" (EXCAP) EA-6B which augmented the frequency coverage of the ECM system. In 1976 the "improved capability" (ICAP) version entered service. The ICAP II EA-6B was the follow-on and a more sophisticated version. Its first deployment was in 1985. It featureed updated operator displays, an inertial navigation system, expanded frequency coverage and a "tactical EA-6B mission support" (TEAMS) system which allows sophisticated pre-flight planning and programming. The US Navy EA-6B Prowler provides an umbrella of protection for strike aircraft, ground troops and ships by jamming enemy radar, electronic data links and communications.