Brazil recently received the first of nine P-3AM maritime reconnaissance aircraft it ordered nine years ago. This project began when the U.S. gave Brazil 13 surplus (and elderly) P-3A aircraft (between 2001 and 2006), so that nine of them could be upgraded in Spain (by AirBus). The rest were to be used for spare parts. All American P-3s, and most foreign ones, have been upgraded to the P-3C standard (which the P-3AM exceeds in some respects.)
The P-3AM refurb included rebuilding parts of the airframe. That’s because the average of all P-3s is about 30 years. The P-3 entered service in 1962. The current version has a cruise speed of 610 kilometers per hour, endurance of up to 13 hours and a crew of eleven. The 35.6 meter (116 feet) long, propeller driven aircraft has a wingspan of 30.4 meters (95 feet). The P-3C can carry about ten tons of weapons (torpedoes, mines, or missiles like Harpoon and Maverick).
The 63 ton P-3 is based on the 1950s era Lockheed Electra airliner. The last P-3 was built in 1990. A more likely replacement for these elderly search planes, are UAVs (Unmanned Aerial Vehicles), like Global Hawk or smaller aircraft like Predator and Reaper. These UAVs typically stay in the air for 24 hours, or more, at a time. What maritime reconnaissance aircraft need, more than anything else, is endurance or, as the professionals like to put it, "persistence."
A fully equipped, for maritime patrol, Reaper costs over $20 million each. Such a reaper can spot ships below night and day, and has cameras that can zoom in on any ship or speedboat for a detailed video close up. A P-3 aircraft can only stay in the air for half as long as a Reaper, but carries more sensors and weapons. A P-3 also requires a larger ground crew, and more maintenance after each flight.
Nevertheless, the demand for Reapers in Afghanistan, and the skill and experience of the P-3 crews, makes the P-3 the most effective, and available, maritime recon aircraft for just about any kind of reconnaissance. Brazil will use its P-3 fleet to patrol its Exclusive Economic Zone (which extends 360 kilometers from the coast). The P-3AM is also equipped to find and destroy hostile submarines. This is one big advantage the P-3 has over UAVs.