Wikipedia

The Lockheed P-3 Orion is a four-engined, 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.[4] The aircraft is easily distinguished from the Electra by its distinctive tail stinger or "MAD" boom, used for the magnetic anomaly detection (MAD) of submarines.

Over the years, the aircraft has seen numerous design developments, most notably in its electronics packages. Numerous navies and air forces around the world continue to use the P-3 Orion, primarily for maritime patrol, reconnaissance, anti-surface warfare and anti-submarine warfare.[1]

A total of 757 P-3s have been built. In 2012, it joined the handful of military aircraft including the Boeing B-52 Stratofortress, Boeing KC-135 Stratotanker, Lockheed C-130 Hercules and the Lockheed U-2 that the United States military has been using for more than 50 years. The Boeing P-8 Poseidon will eventually replace the U.S. Navy's remaining P-3C aircraft.

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