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Mikoyan MiG-31

Mikoyan · Fighter / Attack · Russia · Cold War (1970–1991)

Mikoyan MiG-31 — Fighter / Attack
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The Mikoyan MiG-31 (NATO reporting name Foxhound) is a Soviet / Russian twin-engine, two-seat, supersonic long-range interceptor developed by the Mikoyan Design Bureau as the successor to the MiG-25 'Foxbat'. Service entry with the Soviet Air Force came in 1981, and the type remains Russia's principal long-range air-defence interceptor. As of 2026, 120-150 MiG-31 remain in active Russian Aerospace Forces service, upgraded through the MiG-31BM / MiG-31BSM programmes from 2010 onwards. In its specific role of long-range high-altitude interception, the MiG-31 is one of the few Soviet / Russian aircraft that has not been overtaken by Western counterparts.

The airframe is a tandem-cockpit two-seater 75 ft (22.7 m) long with a 44-ft (13.5 m) wingspan. Empty weight is around 47,000 lb; maximum take-off weight is 101,800 lb. Power comes from two Soloviev D-30F6 afterburning turbofans rated at 21,000 lbf dry and 34,000 lbf in afterburner each — enough thrust for sustained supersonic cruise. Maximum speed is Mach 2.83 (1,860 mph at altitude), placing the MiG-31 among the fastest fighters in service. Service ceiling is 67,500 ft, and combat radius on internal fuel is around 1,000 nmi. Sensors and weapons set the type apart: the Zaslon (NATO 'Flash Dance') passive electronically-scanned-array (PESA) radar was the first PESA fielded on any combat aircraft in 1981, predating Western AESA fighter radar by about 25 years. The MiG-31 carries up to four R-33 (AA-9 Amos) very-long-range air-to-air missiles with a reach of 115 nmi — among the longest-ranged AAMs in service — plus a single port-side GSh-6-23M 23 mm rotary cannon.

Long-range air defence is the MiG-31's core mission, with primary targets being U.S. / NATO long-range systems: the B-52 Stratofortress, B-1 Lancer, AGM-86 air-launched cruise missiles, and other long-range strike assets. The combination of Mach 2.83 dash, 67,500 ft ceiling, R-33 missiles, and the Zaslon PESA enables sustained Mach 2.5+ flight; track-while-scan against 24 or more targets simultaneously; and engagement of four targets at once via the R-33's multi-target guidance.

The MiG-31 has been continuously deployed since 1981. Soviet and later Russian QRA (Quick Reaction Alert) intercepts of U.S. / NATO probing flights have been routine. A more recent role is as launch platform for the Kh-47M2 Kinzhal hypersonic air-launched ballistic missile, fielded from 2017 aboard the specially-modified MiG-31K. The aircraft has also seen action in the Russia-Ukraine war (2022-present), engaging Ukrainian drones and cruise weapons and conducting Kinzhal strikes against Ukrainian infrastructure. The Kinzhal-armed MiG-31K is one of the few in-service hypersonic-strike systems worldwide, though the missile's actual hypersonic performance has been disputed. Roughly 519 MiG-31 were built between 1979 and 1994 at Mikoyan-MiG facilities (now the United Aircraft Corporation MiG branch); 120-150 remain in active Russian service, with upgrade programmes continuing through 2030 and beyond.

For Kids — a shorter, friendlier version

The Mikoyan MiG-31 (NATO code Foxhound) is a Russian high-speed fighter. It first flew in 1975 and entered service in 1981. The MiG-31 is built to fly very fast, very high, and very far. It is one of the fastest fighters in service anywhere in the world.

The MiG-31 has two big Soloviev D-30F6 jet engines, each making 34,000 pounds of thrust with afterburner. Top speed is Mach 2, faster than a rifle bullet. The plane is 75 feet long, longer than a school bus. Two crew sit one behind the other: a pilot in front and a radar officer in back.

The MiG-31 was the first jet in the world with a flat-panel electronic radar, called PESA. This was about 25 years ahead of Western fighters. The radar can track 24 enemy planes at the same time and shoot at 4 of them at once. It also carries the R-33 missile, which can hit targets 115 miles away.

Between 120 and 150 MiG-31s still fly with the Russian Air Force. Some special MiG-31K planes also carry the Kinzhal long-range rocket, one of the few hypersonic missiles in service. The MiG-31 has been upgraded many times since 1981 and will likely stay in service into the 2030s.

Fun Facts

  • Top speed is Mach 2, faster than a rifle bullet.
  • The MiG-31 is 75 feet long, longer than a school bus.
  • The MiG-31 was the first jet with a flat-panel electronic radar (PESA) in 1981.
  • The radar can track 24 enemy planes at the same time.
  • Special MiG-31K planes carry the Kinzhal hypersonic missile.
  • The R-33 missile reaches targets 115 miles away.
  • About 120 to 150 MiG-31s fly with Russia today.

Kids’ Questions

How fast is the MiG-31?

Top speed is Mach 2, faster than a rifle bullet, or about 1,860 mph at high altitude. Few jets can fly this fast. The American SR-71 Blackbird was faster, but only as a special spy plane. The MiG-31 is one of the fastest fighters still in service anywhere.

What is a hypersonic missile?

Hypersonic means faster than Mach 5, or five times the speed of sound. Most missiles travel at Mach 2 to Mach 4. A hypersonic missile is so fast that enemies have very little time to react and try to stop it. The Russian Kinzhal carried by some MiG-31s is one of the few hypersonic missiles in service. America and China are building their own.

Why is it so fast?

The MiG-31 was built to catch American bombers flying high and fast across the Arctic. Each B-1 Lancer or B-52 bomber needs to be caught quickly before it can drop weapons. The MiG-31 carries enough fuel and engine power to chase down any bomber at high altitude. This focus on speed and altitude makes the MiG-31 special.

Variants

MiG-31 (initial 'Foxhound', 1981)
Original 1981 production variant with Zaslon PESA radar and R-33 missiles. Around 280 delivered to the Soviet Air Force, forming the backbone of Soviet long-range air defence.
MiG-31B / MiG-31BS (mid-life)
Mid-life upgrade with the improved Zaslon-A radar and expanded R-33S missile compatibility. Around 100 delivered.
MiG-31BM (2010+)
Upgrade introduced from 2010 with Zaslon-AM radar, new cockpit, and expanded weapons compatibility (R-37 / R-77 / KS-172 missiles). Around 110 airframes brought to BM standard. Currently the principal Russian MiG-31 in-service variant.
MiG-31K (Kinzhal carrier, 2017+)
Specially-modified variant for carriage of the Kh-47M2 Kinzhal hypersonic air-launched ballistic missile. Around 10-15 in service, providing Russia's hypersonic-strike role. Combat-deployed in the Russia-Ukraine war from 2022.
MiG-31D / MiG-31I (proposed anti-satellite)
Proposed anti-satellite variant, never fielded in service. Limited prototype testing took place in the 1990s with experimental anti-satellite missile concepts. Listed for context.

Notable Operators

Russian Aerospace Forces
Sole operator, with around 150 MiG-31 / MiG-31BM / MiG-31K in active service across multiple regiments providing long-range air defence and Kinzhal hypersonic-strike duties. Forward bases include Belaya AB (Irkutsk), Bezerchemka AB (Far East), and Kanachevsky AB (Far East), among others.
Kazakhstan (former)
Inherited a Soviet MiG-31 fleet at 1991 independence and operated it briefly before retirement on service-life and maintenance grounds. Most Kazakhstani airframes were transferred back to Russia.
Foreign / export
None. The MiG-31's specialised long-range interceptor mission and Russian national-security considerations have prevented foreign export. The aircraft's mission profile is uniquely suited to Russian needs — long-range Arctic and Pacific air defence.

Frequently Asked Questions

What is the Kinzhal hypersonic missile?

Kh-47M2 Kinzhal is a Russian air-launched ballistic missile carried by the specially-modified MiG-31K, in service from 2017. Russian-claimed specifications include hypersonic speed of around Mach 10, range of around 1,200 nmi, and a conventional or nuclear warhead. The missile's actual performance has been disputed, with some hypersonic-manoeuvring claims appearing exaggerated; the weapon is essentially a derivative of the Iskander short-range ballistic missile adapted for air launch. Even so, the Kinzhal-armed MiG-31K is one of the few in-service hypersonic-strike systems worldwide, and has been combat-deployed in the Russia-Ukraine war from 2022.

How does MiG-31 compare to F-22 Raptor?

Different generations and roles. The F-22 Raptor is a stealth 5th-generation air-superiority fighter with Mach 2.25 top speed, 65,000 ft ceiling, supercruise, and 2005 service entry. The MiG-31 is a 4th-generation long-range interceptor with Mach 2.83 top speed, 67,500 ft ceiling, no stealth, and 1981 service entry. The MiG-31 holds the lead in maximum speed, ceiling, and weapons reach, but lacks the F-22's stealth, current mission systems, and manoeuvrability. Mission concepts diverge sharply — F-22 for stealth penetration and air superiority, MiG-31 for high-altitude high-speed interception — and the two would not normally meet in the same flight regime.

What is Zaslon radar?

NIIP 'Phazotron' Zaslon (NATO 'Flash Dance') is a passive electronically-scanned-array (PESA) radar — the first PESA fielded on any combat aircraft, in 1981. It supports track-while-scan against 24 simultaneous targets, detection range of around 200 nmi against fighter-class targets, and simultaneous engagement of four targets with R-33 missiles. Zaslon predates Western AESA fighter radar (on F-22 Raptor from 2005, F-15C upgrades from around 2010) by some 25 years. The Zaslon-AM derivative introduced with the MiG-31BM upgrade in 2010 delivers performance comparable to current AESA sets. Zaslon was a Soviet technological achievement that took years to be fully appreciated in the West.

Why does the MiG-31 still fly?

Specialised role and lack of an equivalent replacement. The combination of Mach 2.83 top speed, 67,500 ft service ceiling, long-range air-to-air missiles (R-33 / R-37), and Kinzhal hypersonic-strike role gives the MiG-31 a niche that no other Russian aircraft fully replicates. The Su-57, Russia's 5th-generation fighter, does not match the MiG-31's interceptor performance. The Russian Aerospace Forces has continued investing in upgrades (BM standard, Kinzhal integration) rather than replacement, securing service through 2030 and beyond.

How fast is the MiG-31?

Maximum speed is Mach 2.83 (1,860 mph at altitude), among the fastest fighters in service worldwide. Sustained cruise can hold Mach 2.5+ for extended periods. High speed matters for long-range interception (rapidly closing on target intercept points), coverage of vast Russian airspace from a limited number of bases, and engagement of high-speed threats such as cruise missiles and supersonic strike aircraft. The predecessor MiG-25 'Foxbat' reached Mach 3.2 in some flight tests, but day-to-day use at that speed was limited; the MiG-31 represents the mature high-speed interceptor design.

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