Maritime patrol aircraft
A maritime patrol aircraft (MPA) is a long-range, fixed-wing aircraft that carries sensors to search for surface and subsurface ships. Aircraft of this type typically carry air-to-surface missiles (ASM) to attack ships and homing torpedoes to attack submarines.
With the end of the Cold War reducing the "blue water" submarine threat, carrier-based MPA have been retired. The major types in use, such as the U.S. P-3 Orion and the U.K. Nimrod MR.2 have had additional intelligence, surveillance and reconnaissance equipment so they can be useful long-endurance platforms over land as well as sea.