Wednesday, June 24, 2009

Mig 25


The Mikoyan-Gurevich MiG-25 (Russian: МиГ-25) (NATO reporting name "Foxbat") is a high-supersonic interceptor and reconnaissance/bomber aircraft designed by the Soviet Union's Mikoyan-Gurevich bureau. First flown as a prototype in 1964, it entered service in 1970. With a top speed of Mach 3.2, a powerful radar and four air-to-air missiles, the MiG-25 worried Western observers and prompted development of the F-15 Eagle.

The aircraft's true capabilities were not revealed to the west until 1976 when Viktor Belenko, a Soviet MiG-25 pilot, defected to the United States via Japan. Subsequent analysis revealed a simple-yet-functional design with vacuum-tube electronics, two massive turbojet engines, and sparing use of advanced materials such as titanium. The MiG-25 series had a production run of 1,190 aircraft. The MiG-25 flew with a number of Soviet allies and former Soviet republics and it remains in limited service in Russia and several other nations.

Development

Background

Overflights by American U-2s in the late 1950s revealed a need for higher altitude interceptor aircraft. In 1960, Soviet intelligence learned of the US's development of the high altitude, Mach 3 A-12 reconnaissance aircraft. A high altitude interceptor with high speed would also be needed to defend against the Mach 3 B-70 bomber then under development. A variety of roles were considered for the prospective aircraft, including cruise missile carriers and even a small five to seven-passenger supersonic transport, but the main objective was a high-altitude reconnaissance aircraft and heavy interceptor. The Mikoyan-Gurevich OKB accepted the assignment effective 10 March 1961, carrying the bureau designation "Ye-155" (or "Е-155").

Aircraft design phase

Because of the thermal stresses incurred in flight above Mach 2, Mikoyan-Gurevich OKB constructed the MiG-25 largely from nickel alloy ("Inconel"), but used a small amount of titanium and aluminum alloys in areas particularly susceptible to high aerodynamic drag. The steel components of the MiG-25 were formed by a combination of spot-welding, automatic machine welding and hand arc welding methods. Initially there was concern that jolts from landing would cause the metal welds to crack but this proved not to be the case, and any cracks that did develop in service were easily welded in the field.

Ye-155K3 Reconnaissance prototype (1964)

The first prototype was a reconnaissance variant, designated "Ye-155-R1", and made its first flight on 6 March 1964. The first flight of the interceptor prototype, "Ye-155-P1", took place on 9 September 1964. Development, which represented a major step forward in Soviet aerodynamics, engineering and metallurgy, took several more years to complete. In the meantime several prototypes, under the cover designation "Ye-266" (or "Е-266"), made a series of record-setting flights in 1965, 1966, and 1967.

Series production of the two initial variants, designated MiG-25P ('Foxbat-A') (interceptor) and MiG-25R ('Foxbat-B') (reconnaissance), began in 1969. The MiG-25R entered Soviet Air Force (VVS) service almost immediately, but the service entry of the MiG-25P with the PVO was delayed until 1972. A non-combat trainer variant was also developed for each version, the MiG-25PU ('Foxbat-C') and MiG-25RU, respectively. The MiG-25R evolved several subsequent derivatives, including the MiG-25RB reconnaissance-bomber, the MiG-25RBS and MiG-25RBSh with side-looking airborne radar (SLAR), the MiG-25RBK and MiG-25RBF ELINT aircraft ('Foxbat-D'), and the MiG-25BM ('Foxbat-F') SEAD variant, carrying four Raduga Kh-58 (NATO reporting name AS-11 'Kilter') anti-radiation missiles.

Cameras of the MiG-25RB

The MiG-25 was capable a maximum speed of Mach 3.2 and a ceiling of 90,000 ft (27,000 m), although on Aug. 31, 1977, an E-266M, a specially modified Foxbat, flown by MiG OKB Chief Test Pilot Alexander Fedotov, set the recognized absolute altitude record for a jet aircraft under its own power, reaching 123,523.62 ft (37,650 m) at Podmoskovnoye, USSR in a brief zoom climb. The record is the only recognized absolute record not held by a pilot from the United States.

Although intended for intercepting or threatening high-altitude, high-speed aircraft the MiG-25's maneuverability, range, and close combat potential were extremely limited. Even its high speed was problematic: although sufficient thrust was available to reach Mach 3.2, a limit of Mach 2.8 had to be imposed as the turbines tended to overspeed and overheat at higher speeds, possibly damaging them beyond repair. Inaccurate intelligence analyses caused the West to initially believe the MiG-25 was an agile air-combat fighter rather than an interceptor. In response, the United States started a new program which resulted in the F-15 Eagle.

As the result of Belenko's defection and the compromise of the MiG-25P's radar and missile systems, beginning in 1978 the Soviets developed an advanced version, the MiG-25PD ('Foxbat-E'), with a new RP-25 Saphir look-down/shoot-down radar, infrared search and track (IRST) system, and more powerful engines. About 370 earlier MiG-25Ps were converted to this standard and redesignated MiG-25PDS.

Approximately 1,186 MiG-25s were produced by the time production ended in 1984, and the type was exported to Algeria, Bulgaria (3 MiG-25Rs and 1 MiG-25RUs until 1992), India (until 2006), Iraq, Libya, and Syria.

Design description

A true understanding of the strengths and failings of the MiG-25 by the West came on 6 September 1976, when a PVO pilot, Lt. Viktor Belenko, defected to the West, landing his MiG-25P at Hakodate Airport in Japan. It was carefully dismantled and analyzed by the Foreign Technology Division (now the National Air and Space Intelligence Center) of the United States Air Force, at the Wright-Patterson Air Force Base. After 67 days, the aircraft was returned to the Soviets in pieces. The analysis showed some surprising facts:

  • Belenko's particular aircraft was brand new, representing the very latest Soviet technology.
  • The aircraft was assembled very quickly, and was essentially built around its massive Tumansky R-15(B) turbojets.
  • Welding was done by hand and construction was relatively crude. As in many Soviet aircraft, rivet heads were left non-flush in areas that would not adversely affect aerodynamic drag.
  • The aircraft was built of a nickel alloy and not titanium as was assumed (though some titanium was used in heat-critical areas). The Inconel construction contributed to the craft's massive 64,000 lb (29,000 kg) unarmed weight.
  • The majority of the on-board avionics were based on vacuum-tube technology, not solid-state electronics. Seemingly obsolete, vacuum tubes were actually more tolerant of temperature extremes, thereby removing the need for providing complex environmental controls inside the avionics bays. In addition, the vacuum tubes were easy to replace in remote northern airfields where sophisticated transistor parts may not have been readily available. As with most Soviet aircraft, the MiG-25 was designed to be as rugged as possible. Also, the use of vacuum tubes makes the aircraft's systems more resistant to an electromagnetic pulse, for example after a nuclear blast.
  • The airspeed indicator was redlined at Mach 2.8, with typical intercept speeds near Mach 2.5 in order to extend the service life of the engines. A MiG-25 was tracked flying over Sinai at Mach 3.2 in the early 1970s, but the flight had resulted in the destruction of its engines.
  • Maximum acceleration (g-load) rating was just 2.2 g (21.6 m/s²) with full fuel tanks, with an absolute limit of 4.5 g (44.1 m/s²). One MiG-25 withstood an inadvertent 11.5 g (112.8 m/s²) pull during low-altitude dogfight training, but the resulting deformation damaged the airframe beyond repair.
  • Combat radius was 186 miles (300 km), and maximum range on internal fuel (at subsonic speeds) was only 744 miles (1,200 km). In fact, Belenko had only just reached Japan without running out of fuel; without sufficient fuel for a carefully planned landing, he narrowly missed a commercial airliner taking off, and overran the available runway on landing.

Operational service

Before entering operational service, four MiG-25Rs were temporarily in service with Egyptian Air Force in 1971 under the cover designation of "X-500". All four had EAF markings. They flew over Sinai in pairs roughly 4 times. On 6 November 1971, an Egyptian MiG-25 flying at Mach 2.5 was met by Israeli F-4Es and fired upon unsuccessfully. The Israeli Air Force found it impossible to intercept them, even though Israeli intelligence generally knew when the overflights were scheduled. The MiG-25Rs went back home in 1972, though reconnaissance Foxbats were sent back to Egypt in October 1973, after the Yom Kippur War, and remained there into 1974. A MiG-25 was tracked flying over Sinai at Mach 3.2 during this period. The MiG-25 oversped its engines which led to their destruction. The Israeli Air Force did not have the capability to intercept MiG-25s until it received the F-15 Eagle.

Col. Aleksandr V. Drobyshevsky, confirmed that at least one Soviet pilot, in the USSR's MiG-25 "Foxbat" aircraft, flew recon missions from Egypt into Israel in 1967, just prior to the Six Day War.

The MiG-25 was in service with the Iraqi Air Force during the Iran–Iraq War, but its success against Iranian fighters is largely unknown. Research has shown that as many as sixteen were shot down by Iranian fighters during the period spanning 1978–88 though it is, of course, difficult to determine the validity of these claims. Nevertheless, other historians have offered at least some credential to these reports, citing evidence that Iranian F-14 Tomcats recorded eleven confirmed air-to-air kills of MiG-25s, mostly of the "RB" version, with all kills reportedly being made by the AIM-54 Phoenix.

During the Persian Gulf War, a US Navy F/A-18 piloted by Lt Cdr Scott Speicher was shot down on the first night of the war by air-to-air missile fired most likely by a MiG-25. The kill was reportedly made with a R-40DT missile fired from a MiG-25PDS flown by Lt. Zuhair Dawood of the 84th squadron of the IrAF.

In another incident, an Iraqi MiG-25PD, after eluding eight U.S. Air Force F-15s, fired three missiles at EF-111 Raven electronic warfare aircraft, forcing them to abort their mission. This may have led to the later loss of an F-15 to surface-to-air missiles, due to the lack of electronic jamming.

In yet another incident, two MiG-25s approached a pair of F-15s, fired missiles (which were evaded by the F-15s), and then outran the American fighters. Two more F-15s joined the pursuit, and a total of ten air-to-air missiles were fired at the MiG-25s, though none reached them. According to the same sources, at least one F-111 was also forced to abort its mission by a MiG-25 on the first 24 hours of hostilities, during an air raid over Tikrit.

Two MiG-25s were shot down by USAF F-15Cs during the Gulf War. After the war, in 1992, a U.S. F-16 downed a MiG-25 that violated the no-fly zone in southern Iraq.

In May 1997 an Indian Air Force MiG-25RB was detected flying faster than Mach 2 at least 65,000 ft,over Pakistani territory following a reconnaissance mission into Pakistan airspace, to make the point that the Pakistani Air Force (PAF) has no aircraft in its inventory which can come close to the cruising height of the MiG-25 (up to 74,000 feet). However, from one of PAF's Forward Operating Bases, radar traced the intruder and the F-16As scrambled. India denied the incident but Pakistan's Foreign Minister, Gohar Ayub Khan, believed that the Foxbat photographed strategic installations near the Capital, Islamabad.

On December 23, 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 planes, 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 used in the 2003 invasion, with most hidden or destroyed on the ground. In August 2003, several dozen Iraqi aircraft were discovered buried in the sand. That included two MiG-25s which were excavated and sent to WPAFB's Foreign Technology Division using a C-5B Galaxy. In December 2006, it was announced that one MiG-25 was being donated to the National Museum of the United States Air Force at Dayton, Ohio.

Operators

Current Operators

Former operators

  • Bulgaria
    • Bulgarian Air Force - Three MiG-25RBT (#731, #736 and #754) and one MiG-25RU (#51) aircraft were delivered in 1982. On April 12 1984 #736 crashed near Balchik. The pilot ejected successfully. They were operated by 26th RAB at Dobrich until their withdrawal. In May 1991, the surviving MiG-25s were returned to the USSR in exchange for five MiG-23MLD.
  • India
    • Indian Air Force - Retired from service in July 2006. The Trishul air-base in Bareilly had Foxbats capable of flying up to 80,000 feet
Iraqi MiG-25 found buried under the sand at Al Taqaddum Airbase, Iraq. 29 February 2004


Survivors

Specifications (MiG-25P 'Foxbat-A')

Data from The Great Book of Fighters,[31] International Directory of Military Aircraft[32]

General characteristics

  • Crew: One
  • Length: 19.75 m (64 ft 10 in)
  • Wingspan: 14.01 m (45 ft 11.5 in)
  • Height: 6.10 m (20 ft 0.25 in)
  • Wing area: 61.40 m² (660.93 ft²)
  • Empty weight: 20,000 kg (44,080 lb)
  • Loaded weight: 36,720 kg (80,952 lb)
  • Powerplant: 2× Tumansky R-15B-300 afterburning turbojets
    • Dry thrust: 73.5 kN (16,524 lbf) each
    • Thrust with afterburner: 100.1 kN (22,494 lbf) each

Performance

  • Maximum speed:
    • High altitude: Mach 3.2[3] (3,490 km/h, 2,170 mph); Mach 2.83 (3,090 km/h, 1,920 mph) continuous engine limit[3]
    • Low altitude: 1,200 km/h (650 knots, 740 mph)[32]
  • Range: 1,730 km (1,075 mi) with internal fuel
  • Service ceiling: 20,700 m (with 4 missiles) (67,915 ft)
  • Wing loading: 598 kg/m² (122.5 lb/ft²)
  • Thrust/weight: 0.41
  • Time to altitude: 8.9 min to 20,000 m (65,615 ft)

Armament

Avionics

http://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-25
Posted by Katon Tin Ton at 11:56 PM
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