The Czech Air Force recently retired its last two Russian An-26 transports, after using this type of aircraft for 29 years. The Czechs replaced the 1960s era An-26s with Spanish C-295Ms (which were developed in the 1990s and are cheaper to operate and more reliable). Actually, the An-26s were pretty sturdy and reliable, but older aircraft require more people and money to keep flying.
While first developed in the late 1950s, as the An-24, the design was upgraded in the 1960s to the An-26. The latest version is the An-32. The original An-24 transport entered service in the early 1960s. Over 1,100 AN-24s were built, and over 500 are still in use. Before the end of the 60s, some 600 of an improved version, the An-26, were built, and over 200 are still flying. It's easy to confuse the An-24 and An-26, and journalists (and government officials) often do so. In the 1970s, even more powerful versions (An-30, An-32), entered service, but only about 360 of these were made. India was the principal customer for the 27 ton An-32, which is basically an An-26 with better engines and modifications for tropical operations. This version can carry 6.7 tons of cargo or up to 50 passengers. Max speed is 540 kilometers an hour and range is 2,500 kilometers. The crew consists of two pilots and a loadmaster.
Antonov built the original An-24 series to be simple, rugged and easy to use and maintain. They succeeded. Four decades later, it should not be surprising that nearly a thousand An-24 series aircraft are still working. That's not the first time this has happened. After 70 years, there are still several hundred DC-3 transports working in odd (and often remote) parts of the world.
But with age comes problems. Engines, and other parts of these aging aircraft, are prone to fail at bad moments. A major problem with the An-24 is the shortage of spare parts. The network of factories producing the parts, fell apart when the Soviet Union collapsed in 1991. The parts supply network has been slowly rebuilt, with many factories outside of Russia now producing needed components. Quality of these parts varies, which adds to the sense of adventure one has when flying in these aircraft.