The U.S. Navy is facing a crises in it's ability to keep an eye on the world's oceans. For decades, the navy's principal maritime reconnaissance tool has been the P-3 Orion aircraft. Trouble is, the Orin's are wearing out and there is no replacement in sight. The P-3 is a 63 ton, four (propeller) engine aircraft based on the 1950s Lockheed Electra airliner. The last P-3 was built in 1990, and there are about 170 of them available for service. This is less than half the number available during the height of the Cold War. With a crew of eleven and ever increasing maintenance costs, the Orion is losing out to the newer, cheaper and more capable UAVs. The navy is even experimenting with using the single engine Predator for naval reconnaissance. In addition to cost, and smaller personnel requirements (ten people on the ground or a ship can keep several Predators in operation around the clock), the UAVs also have "persistence". While the P-3s can stay in the air for seven hours, the much smaller Predator can stay up for three times longer. Throughout most of the Cold War, the P-3s were mainly seen as a major weapon against the huge Soviet submarine fleet. With that threat now gone, the large size of the 63 ton P-3 is no longer needed. However, the P-3 is very popular with foreign navies. But the U.S. Navy is having trouble getting money for a manned or unmanned P-3 replacement. Replacing nearly 200 aircraft, probably with a smaller number of more capable planes, will still cost close to $10 billion. The navy has to make up its mind by 2004, and it looks like the result might be a combined force of manned and unmanned aircraft. Some observers, however, see a possibility of an all UAV force.