This year, the pride of the Soviet Air Force celebrated its 40th deployment anniversary. This remarkable Cold War interceptor was designed for one purpose and one purpose alone: to make sure no American reconnaissance plane was ever completely safe over Soviet airspace, regardless of how high and fast their aircraft flew. Iconic American machines like the SR-71 spyplane were threats the Soviet armed forces could not take likely.
These American planes could reach altitudes of almost 100,000 feet (30,482 meters) and fly at speeds that could outrun entire Soviet missile defense systems without so much as deviating from their recon flight course. Something had to be done, and Mikoyan’s first attempt to counter this threat was the MiG-31, based on the MiG-25.
First deployed in 1970, the MiG-25 (NATO code Foxbat) was a remarkable achievement in its own right. The MiG-25 was one of the first jets outside the SR-71 Blackbird to use titanium in parts of its construction.
The plane could touch three times the speed of sound at a service ceiling of around 82,000 feet (24,994 meters). Impressive as those figures are, Soviet pilots who flew the Foxbat claimed it was an absolute devil of a plane to fly. Especially on takeoff and at low altitudes.
To add to concerns, pushing the Foxbat past the Mach three barrier stood a significant chance of shattering the compressor blades in the plane’s two enormous Tumansky R-15 turbojet engines.If such a catastrophic event occurred 20 kilometers above the ground at Mach three, it would almost assuredly result in one or both engines destroying themselves, breaking the plane apart at over 2,000 miles per hour (3,219 kph).
If there was clear situation where the Soviets needed the MiG-25 to shoot down a Blackbird, the Foxbat was all but useless. Soviet leadership realized this from very early on in the MiG-25’s operational history. Not willing to write off the aircraft and cut their losses, the Soviet high command wisely ordered Mikoyan-Gurevich to re-design the Foxbat from the ground up.
The result was an entirely new airplane that NATO codenamed the Foxhound. On first impression, the family resemblance between the MiG-31 and the now-defunct MiG-25 is plain to see. The two jet interceptors’ engines are so enormous that the planes have to be as large as some Second World War bombers just to contain them.
The resemblance ends when the skin of both planes is peeled away. The Foxhound’s fuselage is considerably longer than that of the Foxbat. The new Soloviev D-30F6 turbojet engines generated a scarcely believable 21,000 pounds (93 kN) of thrust and over 34,000 pounds (152 kN) using full afterburners.
Two of these could push the MiG-31 past the Mach three barrier for a more extended period than in the MiG-25. These improvements gave the new Foxhound a real standing chance shooting down not only a Blackbird spy plane, but potentially even nuclear ICBMs with advanced enough missiles.
The missiles fitted to the Foxhound are some of the gold standards of modern warfare. The most iconic of these is the R-33 long-range air-to-air missile first built to counter the SR-71. The Foxhound’s advanced phased scanning array radar can fire up to four R-33s at separate aerial targets.
The MiG-31 never got a chance to shoot down a Blackbird spy plane and little is known about the specifics of the Foxhound’s operational history. Much of this information was likely lost after the fall of the Soviet Union. What is known is that over 500 were produced between 1975 and 1994.
Even with Russia’s next-gen interceptor, commonly referred to as the MiG-41, due to fly in 2025, the Foxhound will remain a mainstay of the Russian arsenal. Harrasing B-52 and F-18 pilots likely for at least another couple of decades.