The Mikoyan MiG-31 (Russian: Микоян МиГ-31; NATO reporting name: Foxhound) is a supersonic interceptor aircraft that was developed for use by the Soviet Air Forces. The aircraft was designed by the Mikoyan design bureau as a replacement for the earlier MiG-25 "Foxbat"; the MiG-31 is based on and shares design elements with the MiG-25.[2] The MiG-31 is among the fastest combat jets in the world.[3] It continues to be operated by the Russian Air Force and the Kazakh Air Force following the end of the Cold War and the collapse of the Soviet Union in 1991. The Russian Defence Ministry expects the MiG-31 to remain in service until 2030 or beyond; that was confirmed in 2020 when an announcement was made to extend the service lifetime from 2,500 to 3,500 hours on the existing airframes.[4][5]
The single-seat MiG-25 could achieve high speed, altitude and rate of climb; however, it lacked maneuverability at interception speeds and was difficult to fly at low altitudes. The MiG-25's speed was normally limited to Mach 2.83, but it could reach a maximum speed of Mach 3.2 or more with the risk of engine damage.[6][7]
Development of the MiG-25's replacement began with the Ye-155MP (Russian: Е-155МП) prototype which first flew on 16 September 1975.[8] Although it bore a superficial resemblance to the MiG-25, it had a longer fuselage to accommodate the radar operator's cockpit and was in many respects a new design. An important development was the MiG-31's advanced radar, capable of both look-up and look-down/shoot-down engagement, as well as multiple target tracking. This gave the Soviet Union an interceptor with the capability to engage the most likely Western intruders (low-flying cruise missiles and bombers) at long range.[1] The MiG-31 replaced the Tu-128 as the Soviet Union's dedicated long-range interceptor,[9] with far more advanced sensors and weapons,[10] while its range is almost double that of the MiG-25.
Like that of its MiG-25 predecessor, the introduction of the MiG-31 was surrounded by early speculation and misinformation concerning its design and abilities. The West learned of the new interceptor from Lieutenant Viktor Belenko, a pilot who defected to Japan in 1976 with his MiG-25P.[11] Belenko described an upcoming "Super Foxbat" with two seats and an ability to intercept cruise missiles. According to his testimony, the new interceptor was to have air intakes similar to the Mikoyan-Gurevich MiG-23, which the MiG-31 does not have, at least in production variants.[12]
Into production
Serial production of the MiG-31 began in 1979.[13][14] A group of four MiG-31 interceptors is able to control an area of air space across a total length of 800 to 900 kilometres (500 to 560mi);[15] its radar possessing a maximum detection range of 200 kilometres (120mi) in distance (radius) and the typical width of detection along the front of 225 kilometres (140mi).[16]
The MiG-31 was designed to fulfill the following mission objectives:[1]
Intercept cruise missiles and their launch aircraft by reaching missile launch range in the shortest possible time after departing the loiter area;
Detect and destroy low flying cruise missiles, UAVs and helicopters;
Long range escort of strategic bombers;
Provide strategic air defense in areas not covered by ground-based, air defense systems.
MiG-31 production ended in 1994.[17] The first production batch of 519 MiG-31s including 349 "baseline models" was produced at the Sokol plant between 1976 and 1988. The second batch of 101 MiG-31DZs was produced from 1989 to 1991. The final batch of 69 MiG-31B aircraft was produced between 1990 and 1994. From the final batch 50 were retained by the Kazakhstan Air Force after the dissolution of the Soviet Union. Of the "baseline models", 40 airframes were upgraded to MiG-31BS standard.[1]
Upgrades and replacement
Some upgrade programs have found their way into the MiG-31 fleet, like the MiG-31BM multirole version with upgraded avionics, new multimode radar, hands-on-throttle-and-stick (HOTAS) controls, liquid crystal (LCD) color multi-function displays (MFDs), ability to carry the R-77 missile and various Russian air-to-ground missiles (AGMs) such as the Kh-31anti-radiation missile (ARM), a new and more powerful computer, and digital data links. A project to upgrade the Russian MiG-31 fleet to the MiG-31BM standard began in 2010;[18] 100 aircraft are to be upgraded to MiG-31BM standard by 2020.[19][20] Russian Federation Defence Ministry chief Colonel Yuri Balyko has claimed that the upgrade will increase the combat effectiveness of the aircraft several times over.[21] 18 MIG-31BMs were delivered in 2014.[22] The Russian military will receive more than 130 upgraded MiG-31BMs, and the first 24 aircraft have already been delivered, Russian Deputy Defense Minister Yuri Borisov told reporters on 9 April 2015.[23]
Russia plans to start development of a replacement for the MiG-31 by 2019. The aircraft will be called PAK-DP (ПАК ДП, Перспективный авиационный комплекс дальнего перехвата – Prospective Air Complex for Long-Range Interception).[24] Development of the new aircraft, designated MiG-41, began in April 2013. Such development is favored over restarting MiG-31 production.[25] In March 2014, Russian test pilot Anatoly Kvochur said that work began on a Mach 4 capable MiG-41 based on the MiG-31.[26][27] Later reports said that development of the MiG-31 replacement is to begin in 2017, with the first aircraft to be delivered in 2020, and the replacement entering service in 2025.[28]
Design
Russian Air Force MiG-31B in 2011
Like the MiG-25, the MiG-31 is a large twin-engine aircraft with side-mounted air intake ramps, a shoulder-mounted wing with an aspect ratio of 2.94, and twin vertical tailfins. Unlike the MiG-25, it has two seats, with the rear occupied by a dedicated weapon systems officer.[29] The MiG-31 is limited to fiveg when travelling at supersonic speeds.[6] While flying under combat weight, its wing loading is marginal and its thrust-to-weight ratio is favorable. The MiG-31 is not designed for close combat or rapid turning.[6]
The wings and airframe of the MiG-31 are stronger than those of the MiG-25, permitting supersonic flight at low altitudes. Like the MiG-25, its flight surfaces are built primarily of nickel-steel alloy, enabling the aircraft to tolerate kinetic heating at airspeeds approaching Mach 3. The MiG-31 airframe comprises 49% arc-welded nickel steel, 33% light metal alloy, 16% titanium and 2% composites.[30] Its D30-F6 jet engines, each rated at 152kN thrust, allow a maximum speed of Mach 1.23 at low altitude. High-altitude speed is temperature-redlined to Mach 2.83 – the thrust-to-drag ratio is sufficient for speeds in excess of Mach 3, but such speeds pose unacceptable hazards to engine and airframe life in routine use.[6]
Electronics suite
MiG-31BM showing its Zaslon phased-array radar
The MiG-31 was among the first aircraft with a phased array radar, and one of two aircraft in the world capable of independently firing long-range air-to-air missiles as of 2013.[31][32][33][34][35]
The MiG-31 was the world's first operational fighter with a passive electronically scanned array (PESA) radar, the Zaslon S-800. Its maximum range against fighter-sized targets is approximately 200km (120mi), and it can track up to 10 targets and simultaneously attack four of them with its Vympel R-33 missiles. The radar is matched with an infrared search and track (IRST) system in a retractable undernose fairing.[6]
The MiG-31 was equipped with RK-RLDN and APD-518[36] digital secure datalinks. The RK-RLDN datalink is for communication with ground control centers. The APD-518 datalink enables a flight of four MiG-31 to automatically exchange radar-generated data within 200km (120mi) from each other. It also enables other aircraft with less sophisticated avionics,[37] such as MiG-23s, 25s, and 29s and Su-15s and 27s[16] to be directed to targets spotted by MiG-31 (a maximum of four (long-range) for each MiG-31 aircraft). The A-50 AEW aircraft and MiG-31 can automatically exchange aerial and terrestrial radar target designation,[38] as well as air defense.[39] The MiG-31 is equipped with ECM of radar and infrared ranges.[40]
The flight-navigation equipment of the MiG-31 includes a complex of automatic control system SAU-155МP and sighting-navigation complex KN-25 with two inertial systems and IP-1-72A with digital computer, electronic long range navigation system Radical NP (312) or A-331, electronic system of the long-range navigation A-723. Distant radio navigation is carried out by means of two systems: Chayka (similar to the system of Loran) and «Route» (similar to the system of Omega).[clarification needed]
Similarly to the complex S-300 missile system,[41] aircraft group with APD-518 can share data obtained by various radars from different directions (active or passive scanning of radiation) and summarize the data. The target can be detected passively (via its emissions of jamming or use of its radar) and/or actively simultaneously from many different directions (with the MiG-31 using its radar). Every aircraft with the APD-518 will have the exact data, even if it is not involved in the search.[13][36][42]
interacting with ground-based automated digital control system (ACS «Rubezh» Operating radius of 2,000 kilometres (1,200mi), can control multiple groups of planes), operating modes of remote aiming, semi-automated actions (coordinate support), singly, and also: to direct on the target missiles launched from the other aircraft.
Digital immune system provides the automatic exchange of tactical information in a group of four interceptors, remote one from another at a distance of 200km (120mi) and aiming at the target group of fighters with less-powerful avionics (in this case the aircraft performs the role of guidance point or repeater).[16]
Radars
Diagram shows how four MiG-31s can keep up to 1,000km (620mi) under control, and how the leader can pass information to friendly fighters.
Adopted in 1981 RP-31 N007 backstop (Russian: Zaslon).[42]
the range of detection of air targets with Zaslon-A: 200km (120mi) (for the purpose of a radar cross-section of 19m2 on a collision angle with probability 0.5)
target detection distance with radar cross-section of 3m2 (32sqft) in the rear within 35km (22mi) with a probability of 0.5[43][44]
number of detected targets: 24 (was originally 10[45])
number of targets for attack: 6 (was originally 4[45][46])
range of automatic tracking: 120 kilometres (75mi)
detection of infrared signature targets: 56 kilometres (35mi)
Effective in the detection of cruise missiles and other targets against ground clutter[45]
Until 2000, it was the world's only fighter in service equipped with phased array radar,[40][47] when the Mitsubishi F-2 entered service with the J/APG-1 active phased array radar.
Able to intercept and destroy cruise missiles flying at extremely low altitudes.[48][39]
Variant differences
The basic differences between other versions and the MiG-31BM are:[46]
The onboard radar complex of the MiG-31BM can track 24 airborne targets at one time, six of which can be simultaneously attacked by R-33S missiles.
Modernized variants of the aircraft can be equipped with anti-radiation missiles Kh-31, Kh-25MR or MPU (up to six units), anti-ship Kh-31A (up to six), air-to-surface class missiles Kh-29 and Kh-59 (up to three) or Kh-59M (up to two units), up to six precision bombs KAB-1500 or eight KAB-500 with television or laser-guidance. Maximum mass of payload is 9,000 kilograms (20,000lb).[citation needed]
The MiG-31M, MiG-31D, and MiG-31BM standard aircraft have an upgraded Zaslon-M radar, with larger antenna and greater detection range (said to be 400 kilometres (250mi) against AWACS-size targets) and the ability to attack multiple targets – air and ground– simultaneously. The Zaslon-M has a 1.4m (4.6ft) diameter (larger) antenna, with 50–100% better performance than Zaslon. In April 1994 it was used with an R-37 to hit a target at 300 kilometres (190mi) distance.[42] It has a search range of 400km (250mi) for a 19–20m2 (200–220sqft) RCS target and can track 24 targets at once, engaging six,[49][50] or 282km (175mi) for 5m2 (54sqft).[51] Relative target speed detection increased from Mach 5 to Mach 6, improving the probability of destroying fast-moving targets.[42] The MiG-31BM is one of only a few aircraft able to intercept and destroy cruise missiles flying at extremely low altitude.[42][52][53]
Cockpit
Front seat cockpit of older MiG-31 variant
The aircraft is a two-seater with the rear seat occupant controlling the radar. Although cockpit controls are duplicated across cockpits, it is normal for the aircraft to be flown only from the front seat. The pilot flies the aircraft by means of a centre stick and left hand throttles. The rear cockpit has only two small vision ports on the sides of the canopy. The presence of the WSO (weapon systems operator) in the rear cockpit improves aircraft effectiveness since the WSO is entirely dedicated to radar operations and weapons deployment, thus decreasing the workload of the pilot and increasing efficiency. Both cockpits are fitted with zero/zero ejection seats which allow the crew to eject at any altitude and airspeed.[6]
Four R-77 (AA-12 'Adder') medium-range missiles (100 kilometres [62mi]) for high-speed target (maneuvering with overload of 12 g).[60]
Some aircraft are equipped to launch the Kh-31P (AS-17 'Krypton') and Kh-58 (AS-11 'Kilter')anti-radiation missiles in the Suppression of Enemy Air Defenses (SEAD) role. Anti-ship missiles Kh-31A (up to six) and air-to-surface missiles X-59 and X-29T (up to three) or X-59M (up to two units), up to six air bombs KAB-1500, or up to eight KAB-500 with a television or laser-guidance. Maximum weight of the combat load is 9,000 kilograms (20,000lb).[61][62]
One Kh-47M2 Kinzhal high-precision ballistic missile with a range of about 2,000km (1,200mi), Mach 10 speed.[63][verification needed] It can carry both conventional and nuclear warheads.[64] This gave the MiG-31 long range strike capabilities for the first time, alongside its primary interceptor role.[65]
Operational history
A side view of a MiG-31 from 790th Fighter Order of Kutuzov Aviation Regiment on the runway of Khotilovo airbase, Tver region.A MiG-31B on left and MiG-31BM on right flying in formation.
Serial production of the MiG-31 began in 1979.[13][14] The MiG-31 entered operational service with the Soviet Air Defence Forces (PVO) in 1981.[66] It was the world's first aircraft with a phased array radar. The MiG-31BM has a detection range of 282km (175mi) for a target with a radar cross-section of 5 square meters.
Export
In 1992 Russia offered the MiG-31 to Finland,[67] which had a selection programme ongoing for a new fighter, but the offer was not submitted to the program, where Russia had submitted the MiG-29.[68] Finland didn't take up the offer,[67] and chose the new fighter from the selection programme.[68]
Syria ordered eight MiG-31E aircraft in 2007 for the Syrian Air Force.[69][70] The order was suspended in May 2009 reportedly either due to Israeli pressure or lack of Syrian funds.[71]
Variants
A front view of a MiG-31 on the ramp of Khotilovo airbase, Tver regionBottom view of a MiG-31BM
Ye-155MP (MiG-25MP)
Prototype modification of the early MiG-31. First flight on 16 September 1975.
MiG-31
First variant which entered in serial production. 349 aircraft were built.
MiG-31M
Development of a more comprehensive advanced version, the MiG-31M, began in 1984 and first flew in 1985, but the dissolution of the Soviet Union prevented it from entering full production.[72][73] One piece rounded windscreen, small side windows for rear cockpit, wider and deeper dorsal spine. Digital flight controls added, multifunction CRT cockpit displays, multi-mode phased array radar. No gun fitted in this model, refueling probe moved to starboard side of aircraft, fuselage weapon stations increased from 4 to 6 by adding two centre-line stations. Maximum TO weight increased to 52,000kg (115,000lb) using increased thrust D-30F6M engines instead of the D-30F6 engines.[74] 1 prototype and 6 flyable pre-production units were produced.
MiG-31D
Two aircraft were designated as Type 31D and were manufactured as dedicated anti-satellite models with ballast in the nose instead of radars, flat fuselage undersurface (i.e. no recessed weapon system bays) and had large winglets above and below the wing-tips. Equipped with Vympel ASAT missiles.[74] Two prototypes were built.
MiG-31LL
Special modification used as a flying laboratory for testing of ejection seats during flight.
MiG-31 01DZ
Two-seat all weather, all altitude interceptor. Designated as MiG-31 01DZ when fitted with air-to-air refueling probe.[74] One hundred produced of DZ variant.[75]
MiG-31B
Second production batch with upgraded avionics and in-flight refueling probe introduced in 1990. Its development was the result of the Soviet discovery that Phazotron radar division engineer Adolf Tolkachev had sold information on advanced radars to the West. A new version of the compromised radar was hastily developed.[76] MiG-31B also have the improved ECM and EW equipment with integration of improved R-33S missiles. Long range navigation system compatible with Loran/Omega and Chaka ground stations added. This model replaced the 01DZ models in late 1990.[74]
MiG-31E
Export version of the MiG-31B with simplified avionics. Never entered in serial production.[74]
MiG-31BS
Designation applied to type 01DZ when converted to MiG-31B standard.[74]
MiG-31BM
After passing state testing in 2008 this modernized variant of MiG-31B was approved for introduction into air force of Russia. 50 planes are modified to MiG-31BM (Bolshaya Modernizatsiya/Big Modernization) standard in accordance with 2011 contract.[77] Efficiency of modernized MiG-31BM is 2.6 times greater than basic MiG-31.[78] The MiG-31BМ's maximum detection range for air targets was increased in the upgrade to 320km (200mi). It had the ability to automatically track up to ten targets, and the latest units can track up to 24 targets and simultaneously engage up to eight targets. The on-board Argon-K is replaced with new Baget 55-06 computer[79] that selects four targets of highest priority, which simultaneously are engaged by long-range R-33S air-to-air missiles.[80] New long range missile R-37 (missile) with speed of Mach 6 and range up to 400km (250mi) is developed during modernization process for use with newly modernized MiG-31.[79] MiG-31BM has multi-role capability as is capable of using anti-radar, air to ship and air to ground missiles. It has some of avionics unified with MiG-29SMT and has refueling probe.[81] MiG-31BM broke world record while spending seven hours and four minutes in the air while covering the distance of 8,000km (5,000mi).[82]
MiG-31BSM
An upgrade of the BS version, it is the latest modernization variant first time contracted in 2014 for modernization of 60 aircraft, it is very similar in some aspects to the BM standard. Unlike the BS standard, aircraft modernized into the BSM standard are equipped with air refueling probe. Improvements were made to the aircraft canopy, where new and better heat resistant glass was used, thus enabling the MiG-31BSM to fly with cruise speed of 3,000km/h (1,900mph) at long distances without any damage. Furthermore, new faster central computer Baget-55-06 is used with addition of multi-functional displays, one for the pilot and three for the weapons operator-navigator. Also there is a new set of navigation equipment. The MiG-31BSM has multi-role capability with ability to use anti-radar, anti-ship and air-to-ground missiles. Main visible difference between the BS and BSM standards is adding of the rear-view periscope above the front cockpit canopy.[83]
MiG-31K
Modified MiG-31BM variant able to carry the hypersonic Kh-47M2 KinzhalALBM. Ten aircraft were modified by May 2018.[84] With this modification and with removed APU for air-to-air missiles, the aircraft gained a sole role of an attack aircraft.[85][86]
MiG-31F
Planned fighter-bomber intended for use with TV, radar and laser-guided ASM weapon systems. Never entered serial production.[74]
Proposed modification for air launch to orbit of small spacecraft with a payload of 160kg (350lb) to 300km (190mi) altitude or 120kg (260lb) to 600km (370mi) altitude orbit.[87]
MiG-31 (Izdeliye 08)
MiG-31 modified into a launch-platform for the Izdeliye 293Burevestnik anti-satellite missile. At least two prototypes are converted. Tests from September 2018.[88]
929th V.P. Chkalova State Flight Test Centre (Akhtubinsk)[92]
From 131[93] to 85[94] MiG-31BM in inventory as of 2020. Deliveries of updated aircraft drawn from older models stocks continue as of 2022.[95][96][97][98][99][100][101] Ten jets have been modified to the MiG-31K version and carry the Kh-47M2 Kinzhal missile as of May 2018.[84] With this modification and with removed APU for air-to-air missiles, the aircraft gained a sole role of an attack aircraft.[85][86]
Russian Naval Aviation
7060th Naval Aviation Air Base (Petropavlovsk-Kamchatskiy/Yelizovo)[102]
10 MiG-31B/BS and 22 MiG-31BM in inventory as of 2020.[103]
Former operators
Soviet Union
Soviet Air Forces aircraft passed to the Russian and Kazakh Air Forces after the dissolution of the Soviet Union.
Soviet Air Defence Forces
Notable accidents
On 4 April 1984, a MiG-31 crashed while on a test flight, killing Mikoyan chief test pilot and Hero of the Soviet Union, Aleksandr Vasilyevich Fedotov and his navigator V. Zaitsev.[104]
On 26 April 2017, a MiG-31 crashed after it was accidentally hit by "friendly fire" during a training session near the Telemba proving ground in Russian Far East.[105] This occurred during a training exercise over the Telemba proving ground in Buryatia; both crew members ejected successfully.[106] While Russian state media did not offer any details, independent investigators discovered from a leaked government document that the aircraft was shot down by an R-33 missile fired from another MiG-31 and that pilot error from both airplanes was at fault. The report also suggested problems with the Zaslon-AM radar and Baget-55 fire control system that might increase the risk of more accidental shootdowns.[107]
On 16 April 2020, a MiG-31 interceptor of the Kazakh Air Force crashed in the country's Karaganda region.[108]
On 8 April 2022, a MiG-31 of the Russian Air Force crashed in the Leningrad region.[109]
Specifications (MiG-31)
MiG-31 3-view drawingMiG-31E landing, with brake chute deployedMiG-31BM take-off with afterburner
Data from Great Book of Modern Warplanes,[2] Mikoyan,[110] Combat Aircraft since 1945,[111] airforce-technology.com,[112] deagel.com[113]
General characteristics
Crew: 2 (pilot and weapons systems officer)
Length: 22.62m (74ft 3in)
Wingspan: 13.456m (44ft 2in)
Height: 6.456m (21ft 2in)
Wing area: 61.6m2 (663sqft)
Empty weight: 21,820kg (48,105lb)
Gross weight: 41,000kg (90,390lb)
Max takeoff weight: 46,200kg (101,854lb)
Fuel capacity: 35,550lb (16,130kg) internals, plus optional external fuel tanks[15]
Hardpoints: 4 × semi-recessed under the fuselage and 4 × underwing pylons with capacity of up to 9,000 kg (20,000 lb) of ordnance.[citation needed] , with provisions to carry combinations of:
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"МиГ-31: реальность и перспективы"[MiG-31: reality and prospects]. Military Industrial Courier (in Russian). 30 April 2013. Archived from the original on 21 December 2014. Retrieved 6 April 2015.
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"Р-40(изделие 46, AA-6 «Acrid»)"[R-40 (product 46, AA-6 "Acrid")]. испытатели.рф (in Russian). Archived from the original on 22 April 2016.{{cite web}}: Check |url= value (help)
"Р-77 (РВВ-АЕ, AA-12 «Adder»)"[R-77 (RVV-AE, AA-12 "Adder")]. испытатели.рф (in Russian). Archived from the original on 10 May 2017.{{cite web}}: Check |url= value (help)
"МиГ-31 (изд.01) FoxHound"[MiG-31 (izd.01) FoxHound]. testpilot.ru (in Russian). Archived from the original on 15 October 2014. Retrieved 6 April 2015.
Markin, Nik (28 November 2014). "ОАК разделит заказ на МиГ-31"[UAC Will Share Order For MiG-31]. AviaPort.ru (in Russian). Archived from the original on 5 December 2018. Retrieved 29 December 2018.
Eden, Paul (2004). "Mikoyan MiG-25 'Foxbat' & Mikoyan MiG-31 'Foxhound'". Encyclopedia of Modern Military Aircraft. London: Amber Books. ISBN1-904687-84-9.
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