The Lockheed Martin P-3 Orion is a four-engine turboprop anti-submarine and maritime surveillance aircraft developed for the United States Navy and introduced in the 1960s. Lockheed based it on the L-188 Electra commercial airliner. The aircraft is easily recognizable by its distinct tail stinger or "MAD Boom", used for the magnetic detection of submarines. Over the years, the aircraft saw numerous design advancements, most notably to its electronics packages. The P-3 Orion is still in use by numerous navies and air forces around the world, primarily for maritime patrol, reconnaissance, anti-surface warfare and anti-submarine warfare.A total of 734 P-3s have been built, and by 2012, it will join the handful of military aircraft such as the Boeing B-52 Stratofortress which have served 50 years of continuous use with its original primary customer, in this case, the United States Navy.
Developed during the Cold War, the P-3's primary mission was to track and eliminate ballistic missile and fast attack submarines in the event of war. Reconnaissance missions in international waters led to occasions where Soviet fighters would "bump" a U.S. Navy P-3 or other P-3 operators such as the Royal Norwegian Air Force. On 1 April 2001, a midair collision between a United States Navy EP-3E ARIES II signals surveillance aircraft and a People's Liberation Army Navy (PLAN) J-8II interceptor fighter jet resulted in an international dispute between the United States and the People's Republic of China (PRC) called the Hainan Island incident.