The Mikoyan-Gurevich MiG-25 (NATO reporting name: Foxbat) is a supersonic interceptor and reconnaissance aircraft that is among the fastest military aircraft to enter service. Designed by the Soviet Union's Mikoyan-Gurevich bureau, it is an aircraft built primarily using stainless steel. It was to be the last plane designed by Mikhail Gurevich, before his retirement. The first prototype flew in 1964 and the aircraft entered service in 1970. Although its thrust was sufficient to reach Mach 3.2+, its speed was limited to prevent engines from overheating at higher air speeds and possibly seriously damaging them, and therefore the operational top speed was limited to Mach 2.83. The MiG-25 features a powerful radar and four air-to-air missiles, and it still has the world record for reached altitude of 38 km. The appearance of the MiG-25 sparked concern in the West and prompted increases in performance requirements for the McDonnell Douglas F-15 Eagle, then already under development in the late 1960s. The capabilities of the MiG-25 were better understood by the West in 1976 when Soviet pilot Viktor Belenko defected in a MiG-25 to the United States via Japan. Production of the MiG-25 series ended in 1984 after completion of 1,186 aircraft. A symbol of the Cold War, the MiG-25 flew with Soviet allies and former Soviet republics, remaining in limited service in several export customers. It is one of the highest-flying military aircraft, one of the fastest serially produced interceptor aircraft, and the second-fastest serially produced aircraft after the SR-71 reconnaissance aircraft, which was built in very small numbers compared to the MiG-25. , the MiG-25 remains the fastest manned serially produced aircraft in operational use and the fastest plane that was offered for supersonic flights and edge-of-space flights to civilian customers.

Design and development

Background

During the Cold War, Soviet Air Defence Forces, PVO (not to be confused with Soviet Air Force, VVS) was given the task of strategic air defence of the USSR. This meant not only dealing with accidental border violations but more importantly defending the vast airspace of the USSR against US reconnaissance aircraft and strategic bombers carrying free-fall nuclear bombs. The performance of these types of aircraft was steadily improved. In the late 1950s, the very high altitude overflights of Soviet territory by the Lockheed U-2 revealed the need for a higher altitude interceptor aircraft than available at that time. In addition, the subsonic Boeing B-47 Stratojet and Boeing B-52 Stratofortress strategic bombers were followed by the Mach 2 Convair B-58 Hustler, with the Mach 3 North American B-70 Valkyrie being developed at that time. A major upgrade in the PVO defence system was required in order to meet the higher and faster American strategic bombers. At the start of 1958, a requirement was issued for manned interceptors capable of reaching 3000 km/h and heights of up to 27 km. Mikoyan and Sukhoi responded. The Mikoyan-Gurevich OKB had been working on a series of interceptors during the second half of the 1950s: the I-1, I-3U, I-7U, I-75, Ye-150, Ye-150A, Ye-152, Ye-152A, Ye-152P, and Ye-152M. The Ye-150 was noteworthy because it was built specifically to test the Tumansky R-15 engine, two of which would later be used for the MiG-25. This led to Ye-152, alternatively known as Ye-166, which set several world records. The Ye-152M (converted from one of the two Ye-152 aircraft) was intended to be the definite heavy interceptor design. But before it was finished, the PVO had selected the Tupolev Tu-128. As the work on the MiG-25 was well under way, the single-engine Ye-152M was abandoned.

Development

Work on the new Soviet interceptor that became the MiG-25 started in mid-1959, a year before Soviet intelligence learned of the American Mach 3 A-12 reconnaissance aircraft. It is not clear if the design was influenced by the American XF-108 Rapier and the A-5 Vigilante. The design bureau studied several possible layouts for the new aircraft. One had the engines located side by side, as on the MiG-19. The second had a stepped arrangement with one engine amidships, with exhaust under the fuselage, and another in the aft fuselage. The third project had an engine arrangement similar to that of the English Electric Lightning, with two engines stacked vertically. Options two and three were both rejected because the size of the engines meant that either of them would result in a very tall aircraft, which would complicate maintenance. The idea of placing the engines in underwing nacelles was also rejected because of the dangers of any thrust asymmetry during flight. Having decided on engine configuration, there was thought of giving the machine variable-sweep wings and a second crew member, a navigator. Variable geometry would improve manoeuvrability at subsonic speed, but at the cost of decreased fuel tank capacity. Because the reconnaissance aircraft would operate at high speed and high altitude, the idea was soon dropped. Another interesting but impractical idea was to improve the field performance using two RD36-35 lift-jets. Vertical takeoff and landing would allow for use of damaged runways during wartime and was studied on both sides of the Iron Curtain. The perennial problem with engines dedicated to vertical lift is they become mere dead weight in horizontal flight and also occupy space in the airframe needed for fuel. The MiG interceptor would need all the fuel it could get, so the idea was abandoned. The first prototype was a reconnaissance variant, designated Ye-155-R1, that made its first flight on 6 March 1964. It had some characteristics that were unique to that prototype, and some of these were visually very evident: the wings had fixed wingtip tanks with a 600 L capacity, to which small winglets were attached for stability purposes, but when it was found that fuel sloshing around in the tanks caused vibrations, they were eliminated. The aircraft also had attachments for movable foreplanes, canards, to help with pitch control at high speed (provisions for canards had previously been installed, but not used, on the Ye-152P). The first flight of the interceptor prototype, Ye-155-P1, took place on 9 September 1964. Development of the MiG-25, which represented a major step forward in Soviet aerodynamics, engineering and metallurgy, took several more years to complete. On 9 July 1967, the new aircraft was first shown to the public at the Domodedovo air show, with four prototypes (three fighters and a reconnaissance aircraft) making a flypast.

Aviation records

The Mikoyan-Gurevich design bureau soon realized that the performance of the new aircraft gave it great potential to set new flight records. In addition to their normal duties, the prototypes Ye-155-P1, Ye-155-R1, Ye-155-R3 were made lighter by removing some unneeded equipment and were used for these attempts. Under Federation Aeronautique Internationale (FAI) classification, the Ye-155 type belonged to class C1 (III), which specifies jet-powered land planes with unlimited maximum take-off weight. Records set included: In all, 29 records were claimed, of which seven were all-time world records for time to height, altitudes of 20000 m and higher, and speed. Several records still stand.

Technical description

Because of the thermal stresses incurred in flight above Mach 2, the Mikoyan-Gurevich OKB had difficulties choosing what materials to use for the aircraft. They had to use E-2 heat-resistant Plexiglas for the canopy and high-strength stainless steel for the wings and fuselage. Using titanium rather than steel would have been ideal, but it was expensive and difficult to work with. The problem of cracks in welded titanium structures with thin walls could not be solved, so the heavier nickel steel was used instead. It cost far less than titanium and allowed for welding, along with heat-resistant seals. The MiG-25 was constructed from 80% nickel-steel alloy, 11% aluminium, and 9% titanium. The steel components were formed by a combination of spot welding, automatic machine welding, and hand arc welding methods. Initially, the interceptor version was equipped with the TL-25 Smerch-A (also referred to as Product 720) radar, a development of the system carried by the earlier Tu-128. While powerful and thus long-ranged and resistant to jamming, the system—due to the age of its design and its intended purpose (tracking and targeting high- and fast-flying US bombers and reconnaissance aircraft)—lacked look-down/shoot-down capability, which limited its effectiveness against low-flying targets. (This is one of the reasons why it was replaced with the Mikoyan-Gurevich MiG-31, whose Zaslon radar has that capability.) By the time the MiG-25 entered service in 1969, this was a serious shortcoming, as strategic bombing doctrine was shifting towards low-level penetration of enemy territory. After Belenko's defection to Japan exposed this flaw to the West, a government decree issued on 4 November 1976 called for urgent development of a more advanced radar. This resulted in the pulse-Doppler radar Sapphire-25 system fitted to the MiG-25PD variant. As an interceptor, typical armament includes four R-40 long-range air-to-air missiles, each fitted with either an infrared seeker (R-40T/TD) or a semi-active radar homing seeker (R-40R/RD) and a maximum range of 35 – against a high-flying target on a collision course. A fuel tank could be suspended under the fuselage. The aircraft could carry unguided gravity bombs to fulfill a rudimentary strike role by using a delivery system developed for nuclear weapons. As the bombs would weigh no more and incur no more drag than its regular load of R-40 missiles, its performance was not impaired, leading to some impressive bombing feats; when released at an altitude of 20000 m and a speed above Mach 2, a 500 kg bomb would have a range of several tens of kilometres. The MiG-25 was theoretically capable of a maximum speed exceeding Mach 3 and a ceiling of 27 km. Its high speed was problematic: Although sufficient thrust was available to reach Mach 3.2, a limit of Mach 2.83 had to be imposed as the engines tended to overspeed and overheat at higher airspeeds, possibly damaging them beyond repair. The design cruising speed is Mach 2.35 (2,500 km/h) with partial afterburner in operation. The maximum speed of Mach 2.83 (3,000 km/h) is allowed to maintain no more than 5 minutes due to the danger of overheating of the airframe and fuel in the tanks. When the airframe temperature reaches 290 °C, the warning lamp lights up, and the pilot must reduce airspeed. The use of a partial afterburner and a cruising flight altitude 19000 – makes it possible to have a range only 230 km less than when flying Mach 0.9 at altitudes 9000 –. The maximum altitude of flight without an afterburner in operation is 12000 m. The poor fuel consumption in the subsonic regime, and hence range, is due to the engines having extremely low pressure ratio of just 4.75 at subsonic speeds. The specific fuel consumption (SFC) of the engines is 1.12lb/(h·lbf) in cruise and 2.45lb/(h·lbf) with afterburners. For comparison purposes, this is 50% worse in cruise than the first generation of F100 engines from the F-15 Eagle, but the SFC with afterburners is actually nearly equal, though the F100 is a far newer engine design.

Production

Full-scale production of the MiG-25R ("Foxbat-B") began in 1969 at the Gorkii aircraft factory (Plant No. 21). The MiG-25P ("Foxbat-A") followed in 1971, and 460 of this variant were built until production ended in 1982. The improved PD variant that replaced it was built from 1978 to 1984, with 104 aircraft completed. Subsequently, the Gorkii factory switched over production to the new MiG-31.

Western intelligence and the MiG-25

Western intelligence first encountered the MiG-25 at the Moscow air show on July 8 and 9, where it was assessed as a fighter-bomber and all-weather interceptor capable of speeds in excess of Mach 2.5. It was not believed at that time to have been in series production. NATO obtained a better understanding of the MiG-25's capabilities on 6 September 1976, when a Soviet Air Defence Forces pilot, Lt. Viktor Belenko, defected, landing his MiG-25P at Hakodate Airport in Japan. The pilot overshot the runway on landing and damaged the front landing gear. Despite Soviet protests, the Japanese invited U.S. Air Force personnel to investigate the aircraft. On 25 September, it was moved by a C-5A transport to a base in central Japan, where it was carefully dismantled and analyzed. After 67 days, the aircraft was returned by ship to the Soviets, in pieces. The aircraft was reassembled and is now on display at the Sokol plant in Nizhny Novgorod. The analysis, based on technical manuals and ground tests of its engines and avionics, revealed unusual technical information:

Later versions

As the result of Belenko's defection and the compromise of the MiG-25P's radar and missile systems, beginning in 1976, the Soviets developed an updated version with a new fire control system, the MiG-25PD ("Foxbat-E"). The MiG-25PD replaced the Smerch-A radar of the MiG-25P with the Saphir-25, based on the MiG-23's Saphir-23, supplemented by an Infrared search and track (IRST) system. The ability to carry R-60 air-to-air missiles was added. A total of 104 MiG-25PDs were built from 1978 to 1984, while existing MiG-25Ps were modified to a similar standard to the PD as the MiG-255PDS. Work was also carried out to improve the MiG-25's performance, with a revised version of the R15 engine, the R15BF2-300, designed with an extra compression stage and running at higher temperatures to give greater power and better fuel consumption. A MiG-25P was fitted with the new engines, with testing of the modified aircraft, unofficially known as the MiG-25M (Ye-155M) beginning in 1974. Planned production aircraft would have received improved radar and armament, but production orders never followed, as the coming MiG-31 showed more promise. Three MiG-25RB reconnaissance/strike aircraft were also modified with the R15BF2-300, which were used to set a series of time-to-height world records (under the designation Ye-266M) on 17 May 1975, and two altitude world records in 1977.

Operational history

Soviet Union

The unarmed "B" version had greater impact than the interceptor when the USSR sent two MiG-25R and two MiG-25RB to Egypt in March 1971, which stayed until July 1972. They were operated by the Soviet 63rd Independent Air Detachment (Det 63), which was established for this mission. Det 63 flew over Israeli-held territory in Sinai on reconnaissance missions roughly 20 times. The flights were in pairs at maximum speed and high altitude, between 17000 and 23000 m. On 6 November 1971, a Soviet MiG-25 operating out of Egypt flying at Mach 2.5 was met by Israeli F-4Es and fired upon unsuccessfully. A MiG-25 was tracked flying over Sinai at Mach 3.2 during this period. The MiG-25 engines went into overspeed, which caused them to be scrapped. Det 63 was sent back home in 1972. Soviet-operated reconnaissance Foxbats returned to Egypt in 19–20 October 1973, during the Yom Kippur War. Det 154 remained in Egypt until late 1974. During the 1970s, the Soviet air force conducted reconnaissance overflights across Iran using its MiG-25RBSh aircraft in response to joint U.S.–Iran reconnaissance operations. The Swedish Air Force observed Soviet Air Defence MiG-25s via radar regularly performing intercepts at 19000 m and 2.9 km behind the Lockheed SR-71 Blackbird at 22000 m over the Baltic Sea in the 1980s.

Syria

On 13 February 1981, the Israeli Air Force sent two RF-4Es over Lebanon as decoys for Syrian MiG-25 interceptors. As the MiGs scrambled, the RF-4Es turned back delivering chaff and using ECM pods. Two IDF/AF F-15As were waiting for the MiGs and shot one of them down with AIM-7F Sparrow missiles. The other MiG was able to escape. In a similar engagement, on 29 July 1981, a Syrian MiG-25 was again downed by an Israeli F-15A, after which a second MiG-25 launched its R-40 missiles at the F-15 and its wingman, but they missed. The first reported activity of Syrian MiG-25 aircraft in the civil war was on 8 February 2014, when two Turkish Air Force F-16s were scrambled to intercept a Syrian MiG-25 which was approaching the Turkish border.

Iraq

Iran–Iraq War

All confirmed air-to-air kills by the MiG-25 were made by Iraq. The MiG-25 was in service with the Iraqi Air Force during the Iran–Iraq War. Iraqi claimed their MiG-25s shot down at least 15 Iranian aircraft during the war, while only one MiG-25 was lost in air combat (one more lost by SAM ) The most successful Iraqi MiG-25 pilot of the war was Colonel Mohommed Rayyan, who was credited with ten kills. Eight of these kills were achieved while he flew the MiG-25PD from 1981 to 1986. In 1986, after attaining the rank of colonel, Rayyan was shot down and killed by Iranian F-14s. For the majority of the air combat Iraqi pilots used R-40 missiles. According to research by journalist Tom Cooper, Iran claimed that ten MiG-25s (nine reconnaissance and one fighter) may have been shot down by Iranian F-14s (one kill was shared with an F-5 ) during the Iran–Iraq war. Only three MiG-25 losses (to ground fire or air combat) were confirmed by Iraq. Confirmed MiG-25 combat losses during the Iran–Iraq war: The MiG-25 was also used as a strike aircraft during the war, targeting Iranian cities.

Persian Gulf War

During the Persian Gulf War, a U.S. Navy F/A-18, piloted by Lieutenant Commander Scott Speicher, was shot down on the first night of the war in the early hours of 17 January 1991 by a missile fired by a MiG-25. The kill was reportedly made with a Bisnovat R-40TD missile fired from a MiG-25PDS flown by Lt. Zuhair Dawood of the 84th squadron of the IQAF, Two IQAF MiG-25s were shot down by U.S. Air Force F-15s on 19 January. The MiGs attempted to hide from the F-15s by using chaff and electronic jammers in order to engage the F-15s untargeted. However the F-15 pilots were able to reacquire the two Iraqi MiG-25s and shot both down with AIM-7 Sparrow missiles. In another incident, an Iraqi MiG-25PD, after eluding eight USAF F-15s at long range, fired three missiles at General Dynamics EF-111A Raven electronic warfare aircraft, forcing them to abort their mission and leave attacking aircraft without electronic jamming support. In a different incident, two MiG-25s approached a pair of F-15s, fired missiles at long range which were evaded by the F-15s, and then outran the American fighters. Two more F-15s joined the pursuit, and a total of 10 air-to-air missiles were fired at the MiG-25s, though none reached them. On 30 January 1991, an IQAF MiG-25 damaged a USAF F-15C with a R-40 missile in the Samurra Air Battle. Iraq claims it was shot down and fell in Saudi Arabia. After the war, on 27 December 1992, a U.S. F-16D downed an IQAF MiG-25 that violated the no-fly zone in southern Iraq with an AIM-120 AMRAAM missile. It was the first USAF F-16 air-to-air victory and the first AMRAAM kill. On 23 December 2002, an Iraqi MiG-25 shot down a U.S. Air Force unmanned MQ-1 Predator drone, which was performing armed reconnaissance over Iraq. This was the first time in history that an aircraft and an unmanned drone had engaged in combat. Predators had been armed with AIM-92 Stinger air-to-air missiles and were being used to "bait" Iraqi fighter aircraft, then run. In this incident, the Predator did not run, but instead fired one of the Stingers, which missed, while the MiG's missile did not. No Iraqi aircraft were deployed in the U.S. invasion of Iraq in 2003, with most Iraqi aircraft being hidden or destroyed on the ground. In August 2003, several dozen Iraqi aircraft were discovered buried in the sand.

India

The MiG-25 was kept a guarded secret in India, designated Garuda after the large mythical bird of Vishnu from Hindu scriptures. It was used extensively in the Kargil War and Operation Parakram, conducting aerial reconnaissance sorties over Pakistan. In May 1997, an Indian Air Force Mikoyan MiG-25RB reconnaissance aircraft created a furor when the pilot flew faster than Mach 3 over Pakistani territory following a reconnaissance mission into Pakistan airspace. The MiG-25 broke the sound barrier while flying at an altitude of around 20000 m, otherwise the mission would have remained covert, at least to the general public. The Pakistani Government contended that the breaking of the sound barrier was a deliberate attempt to make the point that the Pakistan Air Force (PAF) had no aircraft in its inventory that could come close to the MiG-25's cruising altitude (up to 74000 ft). India denied the incident but Pakistan's Foreign Minister, Gohar Ayub Khan, believed that the Foxbat photographed strategic installations near the capital, Islamabad. Lack of spare parts and India's acquisition of unmanned aerial vehicles and satellite imagery eventually led to its retirement in 2006. Subsequently, six out of the seven surviving MiG-25s (the eighth aircraft was lost in a crash in 1994) have been preserved at various locations in India. An aerial observation of the solar eclipse of 24 October 1995 over India was conducted by a MiG-25, which took images of the eclipse at an altitude of 25000 m.

Libya

Libya was a major user of the MiG-25 as it imported 96 MiG-25PD interceptor, MiG-25PU trainer and MiG-25RBK reconnaissance aircraft in the late 1970s and early 1980s. During the 1980s, Libya confronted the United States over some claims over the extension of its territorial waters. These incidents prompted a number of encounters between the opposing forces as it happened during the Gulf of Sidra incident (1981) with the Libyan MiG-25s taking part in them. During the following years, the Libyan MiG-25 fleet was grounded, lacking maintenance. As MiG-25s had been grounded for several years, NATO attacks spared them during the Libyan Civil War (2011). In 2014 and 2015, the Libyan forces under the New General National Congress controlled a number of former LARAF airframes, that were retired and stored before the Libyan Civil War in 2011, among them a number of MiG-25s. Technicians started working on some of the airframes to press them back to service in the fight against the opposing internationally recognized Libyan government forces. On 6 May 2015, a New General National Congress MiG-25PU crashed near Zintan while attacking the civilian airport controlled by the opposing internationally recognized Libyan government, the pilot ejected and was captured by opposing forces which also claimed they downed the jet. The jet may have been on one of its first flights after re-entering service.

Variants

Prototypes

Interceptors

Reconnaissance and strike versions

Conversion trainers

Operators

Former operators

Aircraft on display

Specifications (MiG-25P / MiG-25PD)