The U.S. Navy spending nearly $10 million per aircraft to refurbish the wings of 14 P-3C maritime patrol aircraft. This is part of an effort to keep enough P-3Cs flying until the new P-8A enters service in eight years. The wing fatigue is a symptom of age. The P-3 was originally designed to spend 7,500 hours in the air before retirement. But the average of the navy P-3s is 30 years, and, because of lots of refurbishment and diligent maintenance, the average air time is 16,000 hours.
This has not been easy. Four years ago, the navy grounded a quarter of its 161 P-3C maritime patrol aircraft because of age related metal fatigue in the wings. This sort of thing is common with older aircraft, especially those that spend most of their time flying over salt water. The navy believes that it would have all, or most, of the grounded aircraft back in service by now. But not all the work is done, about a third of 140 P-3s still in service are unavailable because of these age related repairs. The aircraft have to be partially disassembled for replacement parts or reinforcing elements to be installed, and the process can take nearly a year per aircraft.
The P-3 entered service in 1962. The current version (the P-3C) has a cruise speed of 610 kilometers per hour, endurance of up to 13 hours and a crew of eleven. The 37.4 meter (116 foot) long, propeller driven aircraft has a wingspan of nearly 33 meters (100 feet). The P-3C can carry about ten tons of weapons (torpedoes, mines, or missiles like Harpoon and Maverick).
The 63 ton aircraft is based on the 1950s era Lockheed Electra airliner. The last P-3 was built in 1990. Likely replacements for these elderly search planes, are UAVs (Unmanned Aerial Vehicles), like Global Hawk or smaller aircraft like Predator. 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."