In November 1971, two Israeli fighter jets raced to intercept an unidentified aircraft. The F4 Phantoms are among the fastest jets in the world, but they’re not fast enough. Because they’re chasing a MiG-25. A plane that can fly so fast and high, it can outrun any fighter or air defense system. For nearly a decade, the Soviet Union’s MiG-25 will remain a complete mystery and leave western intelligence scrambling for answers.
In the opening years of the Cold War a new kind of weapon emerged, the intercontinental bomber. An aircraft with enough range to reach nearly any part of the world to deliver a nuclear strike. America’s first intercontinental bomber not only flew further, it flew higher and faster than any bomber before it, making it extremely difficult to intercept. And it started a decade-long trend of building strategic bombers that flew ever higher and faster. The Soviet Union responded by building increasingly capable fighter-interceptors to try and stop them.
But by the late 1950s, Soviet intelligence had learned that the Americans were developing a new state-of-the-art bomber that would fly so high and fast, it would render the entire Soviet Air Force virtually obsolete. The XB-70 was so cutting edge, that only a few years earlier it would have been impossible to build. But the Americans were aiming to have the bomber ready in just a few short years.
For Soviet leadership, a sense of panic set in. As the largest country in the world, there were over twenty two million square
kilometers of airspace guard. At any moment, American bombers could emerge from the north, or from bases in the east, or NATO allied countries in the west. And only a handful of supersonic bombers would be enough to overwhelm air defenses. The Soviet Union would have just a few short years to design and build a new interceptor to match the incredible performance of the upcoming B-70. It would have to be as fast as Soviet ingenuity could make it, and developed in record time. But to effectively guard the country’s enormous airspace, they’d also need to mass produce the new jet by the hundreds.
The MiG-25 was the Soviet Union’s answer, an interceptor that would overcome the odds with brute force. To catch the XB-70, engineers would need to equip the MiG with enormously powerful engines. But there wouldn’t be time to develop new ones.
Instead, they’d make due with a turbojet originally built to power cruise missiles and reconnaissance drones. They were the largest engines ever put on a fighter, but they were essentially disposable. It meant that initial versions of the MiG had engines with a service life of just 150 hours. At intercept speeds , the MiG-25 would have to withstand serious kinetic heating, with some parts reaching 300 Celsius. But lightweight heat-resistant titanium was just too difficult to produce on a mass scale. So engineers built the jet largely out of heavy nickel-steel alloy, a material that could be quickly welded together and easily repaired at even the most remote and ill-equipped airbase. But it meant the more than forty thousand pound jet could never be maneuverable, a characteristic
considered irrelevant for its mission. To spot enemy bombers, the MiG-25 was equipped with a colossal 600 kilowatt radar designed to detect high flying aircraft up to a hundred kilometers away and burn right through their jamming devices. And it would only need one kind of weapon. Four of the largest air-to-air missiles ever produced. Along with the interceptor, there would also be a dedicated reconnaissance version with powerful surveillance cameras, increased range, and an even higher service ceiling. Some
versions could even be equipped for high altitude bombing. But the vast majority of MiG-25s would be built as dedicated interceptors.
Mass production began in 1969, and at one point, one hundred MiG-25’s were rolling off assembly lines every single month. The Mig-25 would fly higher and faster than any combat jet in history, and it would have a profound effect on the Cold War. Just not in the way the Soviets were expecting. In 1967, the Soviet Union put on a massive airshow. And they made sure the Americans were watching. The event was even broadcast in English for western audiences.
The Soviets unveiled several new aircraft for the very first time, but they saved the best for last. In the final 10 minutes, three prototype MiG-25s were sent roaring past the audience. It was the first time anyone outside of the Soviet Union would see the new aircraft. And for western intelligence, it set off alarm bells.
The grainy footage revealed an aircraft with all the hallmarks of an agile fighter, the unusually large wings suggested extreme maneuverability. Enormous air intakes hinted at massive engines and experts suspected the use of advanced lightweight titanium.
But what worried them the most, was that the plane looked eerily similar to concepts for America’s next-generation air superiority fighter. A jet that wouldn’t be ready for another ten years. In Washington, military planners struggled to understand how the Soviets could have leapfrogged so far ahead. Because only a few months later, the Soviet Union started registering incredible new world records for speed and altitude. And the media soon caught wind, spreading fears that the mysterious new jet could outperform anything built by the West. The US Air Force Chief of Staff even publicly admitted that for the first time, the Soviet’s had a jet that the United States couldn’t match.
The perceived threat posed by the mysterious new jet motivated the US to drastically increase performance targets for its next-generation fighters. But for years, the Americans were desperate for any information they could get. They’d catch another glimpse in 1971, when Israeli radar controllers began tracking MiG-25’s over the Saini peninsula. The jets were clocked flying at more than two and half times the speed of sound, at an altitude of over twenty kilometers. At one point, they even tracked one of the MiGs accelerating beyond Mach 3. But the jets flew so high and fast, no fighter in the world could catch them.
For over a decade, the MiG-25 remained a mystery and continued to worry western intelligence. But that was about to change in the most dramatic way possible. On September 6th, 1976, the Soviet Union’s most secretive jet showed up seemingly out of nowhere over northern Japan. It then made a dramatic crash landing at a sleepy commercial airport, Nearly colliding with an airliner and skidding right off the end of a runway. It was the first time anyone in the West would see a MiG-25 in person. And as curious onlookers gathered, no one seemed to know where it had come from or how it got here. Piloting the MiG was 29 year old Viktor Belenko. He was quickly taken into custody where he explained that he escaped the Soviet Union to seek asylum in the United States. Disillusioned with life in the Soviet Union and harsh conditions at his airbase, Belenko had planned his escape for months. While on a training exercise over the sea of Japan, he reported engine trouble, giving him a chance to fall back from his group.
Belenko then descended low enough to evade radar detection. Once out of Soviet air space, he set course for the nearest Japanese airbase. But with limited fuel and difficulty navigating, he was forced to find the nearest airport. Belenko was well aware that his MiG-25 was a prized possession and he provided invaluable information to western intelligence, who shipped his MiG to a
nearby airbase to examine every inch of it. And they were in for the shock of a lifetime. The MiG-25 obviously wasn’t the agile fighter they were expecting.
Its heavy stainless steel airframe severely limited maneuverability and the large wings were needed just to keep the jet airborne. The engines, while powerful enough to exceed Mach 3, couldn’t sustain those speeds without permanent damage. Meaning the practical limit was around Mach 2.8. The MiG’s radar was powerful but lacked look-down capability, meaning it couldn’t track low flying targets.
The compromises that Soviet engineers were forced to make were now glaringly apparent. But they wouldn’t have mattered much for intercepting a high-altitude, supersonic bomber like the B-70. But the B-70 never made it into production. Instead, the Americans switched their tactics from high speed and high altitude, to low altitude radar and defense evading aircraft. Leaving western intelligence perplexed as to why the MiG-25 was produced in such large numbers. The only other aircraft the interceptor would potentially have to guard against were a handful of reconnaissance aircraft. The same media that once stoked fears about a Soviet super-plane now openly mocked the MiG as a crudely built machine that was more or less useless in combat. An inferior aircraft that proved the Soviets were behind in technology.
Belenko’s defection outraged Soviet leadership, who demanded that he return to the Soviet Union along with the stolen MiG. Instead, Belenko was granted American citizenship, while his MiG was sent back to the Soviet Union in dozens of pieces. The Americans had learned everything there was to know about the MiG-25, and they now understood critical components of the Soviet air defense system. With the MiG-25 so thoroughly compromised, Soviet engineers had to work around the clock to modernize the aircraft. Equipping the MiG-25 with more powerful and reliable engines, a more sophisticated look-down radar, and the ability to field a wider range of missiles.
Meanwhile, older versions of the jet, no longer a closely guarded secret, were exported to other countries. In all, nearly twelve hundred MiG-25s were produced. But more than fifty years later, the MiG-25 is still the fastest fighter jet ever built. An aircraft that would set twenty nine World Records. In 1977, a MiG-25 climbed to an incredible altitude of 123,000 feet, setting a record that still stands today.
Although the aircraft had been built to intercept high altitude bombers, downgraded export versions even saw moderate success in combat. But by the late 1970s, the Soviet Union had moved on. Because the development of a next-generation interceptor was well underway. A jet that would have cutting edge avionics, sophisticated engines, and a radar and weapons control system so advanced, it could engage multiple targets simultaneously from a hundred kilometers away and even link with other fighters to coordinate an attack. In the process, instantly upgrading the capabilities of older Soviet fighters. Where the MiG-25’s design was about brute force, the new MiG-31 would use the state-of-the-art to become the world’s most formidable interceptor.