The Grumman F-14 Tomcat was developed for the U.S. Navy as its main fighter-interceptor, introduced into service in 1974. Unlike the F-15 and F-16, which were exported to a number of allied countries, the only foreign operator of the F-14 was Iran, which placed an order in 1974 for 80 planes, 714 Phoenix missiles, and spare parts and engines for ten years. The planes started to be delivered in January 1976, with crews receiving training in the U.S.
After the Islamic revolution in 1979 and subsequent hostage crisis at the U.S. Embassy in Tehran, the U.S. imposed an arms embargo on Iran which prohibited the provision of any equipment and services to maintain the Iranian F-14s. The F-14, with its two troublesome TF-30 engines, complicated swing-wing system, and complex avionics, has a reputation for being a high-maintenance aircraft, so how did Iran keep its fleet of F-14s flying and manage to rack up a long list of combat victories during the Iran-Iraq war of 1980–1988, and how does the country continue to keep the fleet of 41 F-14s operational a full 17 years after the fighter was retired by the U.S. Navy?
The older level of technology and the much larger number of users and much larger number of units, meant much greater supply of spare parts on the international black market.
And Iran is doing updates itself.
One interesting non-update is the lack of trying to shoehorn in a turbofan such as Boeing and IAI wanted to do:
The Russian RD-33 and its Chinese counterpart seem a good fit: