The History Of The Oldest Fighter Jet Still In Service Today

Fighter jets are some of the most important pieces of equipment in the world's largest and most powerful militaries. They provide aerial dominance, defend airspace and other aircraft carrying potentially important people and sensitive materials, and are able to intercept enemy attacks, be they bombers, rockets, or other fighter jets. It is no surprise, then, that the world's superpowers place great stock in them, funding their militaries to develop the most cutting-edge aerial technology. In 2025, it was reported that the Pentagon is throwing everything it has behind the new F-47 sixth-generation stealth fighter, a cutting-edge fighter jet that will keep the United States ahead of rivals, including China and Russia, when it comes to aerial capability. (Some models, such as the F-22 Raptor, were banned from export for this reason.) At the same time, the Air Force looks to retire older models it deems unfit for modern warfare, such as the long-serving A-10.

But this isn't always the case. In fact, some air forces keep the same model of planes in operation for decades, with some aircraft built before the Vietnam War still in operation. One of these is the Mikoyan-Gurevich MiG-21, a retro fighter jet that has been used around the world since it first came into service more than six decades ago. It was initially tested in 1955 and went into service in 1960 in the Soviet Union, outperforming the more dangerous designs of the previous generation. And surprisingly, the MiG-21 is still used today.

Designed by the Soviet Union as a second-generation fighter jet, the MiG-21 is a single-seat, single-engine aircraft which quickly established itself as a reliable model within the Soviet Air Force. Its lightweight design meant it could easily reach Mach 2, an impressive feat for an aircraft originating from the 1950s. In its early days, it was used primarily as an interceptor, but like other models of the era soon became heavily modified to accomplish various tasks and missions required of it. It featured in many Soviet conflicts, including the disastrous Soviet invasion of Afghanistan in 1979.

The success of the MiG-21 meant that it wasn't reserved purely for the Soviets. It became an in-demand aircraft for export, with 6,000 units in operation in the militaries of more than 50 countries, particularly in Eastern Europe, Asia, and Africa, with China and India the biggest users of the model. Eleven thousand MiG-21 fighter jets have been built, making it the most mass-produced jet of all time. The last standing fleet in Europe was in Croatia, which was stood down as recently as 2024, while hundreds are in service in India and elsewhere, though most remaining MiG-21 nations are planning to upgrade. Russia themselves have since developed numerous new models.

It may seem surprising that such powerful countries continue to operate aircraft that are arguably so outdated, but the truth is that the United States Air Force also continues to employ older models in its day-to-day operations, for a variety of purposes. This includes fighter jet models such as the formerly mentioned A-10.

The oldest model currently in use in the U.S. Air Force, the A-10C Thunderbolt II, was first produced and delivered to the Davis-Monthan Air Force Base, Arizona, in October 1975. Though designed as a fighter, it has been used as a support vehicle for ground forces, its maneuverability making it a worthy adversary for maritime craft and armored ground vehicles.

Capable of speeds of up to 420 miles per hour, it has been one of the most-used high-speed military jets of the last half century. Until recently, hundreds were deployed overseas, though that has steadily been shrinking. At present, fewer than 100 remain in service, with the rest expected to be retired in 2026.