Taiwan has nearly completed its effort to upgrade and overhauling the twelve P-3C maritime reconnaissance aircraft purchased from the United States in 2008. These were aircraft taken from the several hundred that the United States had retired since the end of the Cold War. At the time the average age of the U.S. P-3Cs was 28 years. The 2008 deal with Taiwan called for eight of the aircraft to be rebuilt in Taiwan, and for a P-3C service center to be built in Taiwan to handle that and future maintenance and refurbishment as well. The Taiwanese got the latest American anti-submarine electronics for the P-3C. Deliveries of the refurbished aircraft began in late 2013 and so far eight have arrived with the other four to be in service by the end of 2015.
The refurbished P-3Cs replace a fleet of 26 second-hand American S-2 anti-submarine aircraft. These two engine aircraft originally operated off American carriers. Taiwan obtained them in 1976, and refurbished them in the early 1990s. The 1950s era, eleven ton S-2 was replaced in American service by the jet powered S-3 in the late 70s. The Taiwanese S-2s carry similar equipment to that found in early model P-3Cs. The last of 1,284 S-2s was built in 1968 and despite diligent and impressive maintenance efforts the nearly half century old S-2s are difficult to keep operational. In fact only about ten are available for service at any time. Lacking air conditioning the S-2s are not popular with their crews when the tropical climate of Taiwan really heats up. In fact, most have been retired and used for spare parts to keep some going until the P-3Cs are fully operational in 2017. That will mean the Taiwanese S-2s served for half a century.
The S-2 was exported to 14 other countries but only Taiwan and Argentina still operate any of them. There are some civilian operators who use the S-2 to fight forest fires (by dropping water or fire retarding chemicals instead of torpedoes).