In the 1960s, Soviet air force command was worried that the country is vulnerable to high-speed nuclear bombers fielded by the United States Air Force, like the Convair B-58 Hustler. Powered by four General Electric J79-GE-1 turbojet engines and capable of reaching Mach 2 speeds, B-58 was the first supersonic USAF bomber. It was introduced in 1960 and was a source of great concern for the Soviet air defense planners. To make things even worse, in 1964 USAF launched another nuclear bomber, B-70 Valkyrie. A futuristically looking plane that was even faster, reaching Mach 3 and becoming an even greater headache for the Soviets. Something had to be done and fast.
The task was taken by the famous Mikoyan-Gurevich bureau. As it turned out, it was the last plane legendary Mikhail Gurevich designed before going into the well-deserved retirement. The designers came up with a monster built around two Tumansky R-15 engines. These power plants were the most powerful jet engines Soviet had at their disposal at the time.
On paper, the latest addition to the Soviet Air Force was highly impressive. It could fly at a sustained speed of Mach 2.83, reaching even Mach 3 and higher for short bursts, but you needed an extra pair of engines waiting for you at the airport because the old ones were thrashed after such exhibition. It carried 4 R-40 Air to air missile that had interceptor role and could reach the height of sixty-five thousand feet. A reconnaissance version was packed with the best high-tech cameras and spying equipment the Soviet Union had to offer at the time and had an even higher ceiling.
It was Americans turn to get worried. They first learned of the new design in 1967, when Soviets revealed MiG-25 at the Moscow Domodedovo Airport. According to Western intel, not only did they manage to close the gap in their air defenses, but also gained a formidable fighter that could easily outrun every airplane, except SR-71 Blackbird, USAF had in its arsenal. MiG-25 was considered the greatest threat to the national security since the beginning of the Cold War.
The first step towards eliminating the threat was changing the requirement of the new fighter design being developed at the moment. Instead of a small, multipurpose plane, the focus shifted to a fast and pure air superiority fighter. The program resulted in McDonnell Douglas F-15 Eagle, one of the most successful modern fighters, with more than 100 confirmed kills and not a single air to air combat loss.
The truth about MiG-25 became known on September 6th, 1976, when Lt. Viktor Belenko landed his plane at Hakodate Airport in Japan. Belenko became one of the most famous defectors in history, solely on the fact that he brought with himself one of the most guarded secrets in the Soviet Union. His plane was brand new and allowed Western engineers to see first hand what Soviet state of the art technology looks like.
It turned out that MiG-25 was vastly overrated. It had many flaws, mostly due to the inadequate manufacturing process. The Soviet Union lacked the ability to produce titanium and a large part of the airframe was built from steel, resulting in a very heavy airplane. The entire electronic suite was based on vacuum tubes technology. Although not as sophisticated as solid-state electronics its Western counterparts used, it has several advantages. Most importantly, the onboard radar, Smerch-A, lacked look down – shoot down ability, making MiG-25 useless against low-flying targets.
Soviets got their plane back 67 days later, in pieces, mostly because American engineers didn’t have enough time to put it back together. Realizing that crucial radar and missile technologies were compromised, they started working on a new version, MiG-25PD. This is the most numerous version of MiG-25.
Despite its drawbacks, MiG-25 had some success in combat. It saw action for the first time in 1971 when a detachment of Soviet Air Force was flying recon flights over Sinai from Egyptian bases. One of MiG-25s was tracked at Mach 3.2 during that time, but its engines were destroyed and had to be replaced after the flight.
MiG-25 was flown by Syrian Air Force as well, albeit with not much success. They lost two to Israeli F-15 in 1981. Iraqis were far more successful and their best MiG-25 pilot, Colonel Mohammed Rayyan, is credited with 10 kills.
In the end, MiG-25 wasn’t very successful in terms of design. It was built for a specific mission, but it was never used in that role and the design was far too rigid to be adapted for a different task. Its most important contribution is that it served as a basis for the development of a far better version, Mig-31.