The U.S. has agreed to upgrade six Greek P-3B maritime patrol aircraft to the current P-3C standard and refurbish components of the aircraft to extend their use for another 15,000 flight hours. All this will cost about $84 million per aircraft. Four of the P-3Bs are currently on active duty while the other two are in storage. The P-3Bs are over twenty years old and near the end of their useful lives, unless refurbished. Greece wanted to replace the P-3Bs with newer aircraft, but that would cost two to three times more than refurbishing the P-3Bs. Greece has to consider the cheaper option because it is still suffering from a banking crises caused by decades of getting by on borrowed (often illegally) money.
Meanwhile the U.S. Navy is replacing its P-3Cs with the P-8A, while other countries are getting by with even cheaper solutions in the form of business jets equipped for maritime reconnaissance. Some are using UAVs (Unmanned Aerial Vehicles), but it will be another decade before UAVs are ready to completely replace manned marine patrol aircraft. Large UAVs like the 14 ton Global Hawk and smaller ones like the 1.1 ton Predator are assuming some maritime patrol duties already. These are not yet as effective as manned aircraft for chores like anti-submarine warfare. 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."
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 36 meter (116 foot) long, propeller driven aircraft has a wingspan of 31 meters (nearly 100 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.