Configuration and design. As to the MiG-31 configuration, it is very similar to that of the MiG-25P. It is a full-metal high-wing monoplane of regular aerodynamic configuration with a trapezoid wing, two-fin vertical and all-moving horizontal control surfaces, two engines in the rear part of the fuselage, and retractable tricycle landing gear. Two-seat aircraft has a re-designed lighter airframe (see table).
| Steel | Titanium alloys | Aluminom alloys | |
|---|---|---|---|
| MiG-25 | 80% | 8% | 11% |
| MiG-31 | 50% | 16% | 33% |
The radar compartment is in the forward fuselage. The crew – a pilot and a systems operator – flies in a two-seat pressurised cockpit in the K-36DM ejection seats in tandem. The canopy has two up-and-back tilting parts. In the MiG-31Bs, there is an extendable flight refuelling probe on the left in front of the cockpit. On the fuselage bottom surface, in front of the wheel wells, there are brake flaps that at the same time serve as landing gear well doors.Wing panels are of small elongation with a 41 degree sweep angle along the leading edge. There is a fence on the top surface of each half-wing. The trailing edge is equipped with slot flaps and ailerons, while the leading edge has a four-section deflectable flap. The panels of the all-moving horizontal surfaces can deflect both synchronously (pitch control) and differentially (roll control). The twin vertical stabilisers with a flare angle of 8 degrees are equipped with rudders. The bottom rear fuselage has two additional 12 degree outward-canted fins. The MiG-31 features mechanical actuator-boosted control system.
The main gear struts are of original design. Instead of one wheel with a diameter of 1,300 mm like that of the MiG-25, they are equipped with a trolley of two 950×300 mm wheels. The rear wheel does not go in the wake of the forward wheel, but is shifted somewhat outward. The nose gear has two wheels with dimensions of 660x200mm. The powerplant comprises two D-30F-6 bypass turbojet afterburner engines developing a thrust of 9,500 kgf at max mode and 15,500 kgf in full afterburner. Internal fuel storage in fuselage and fin tanks is 19,500 litres. The aircraft has side air intakes with a square cross-section controlled by moving horizontal panels. There can be another two external tanks attached to the underwing hard points with the 2,500 litres capacity each. In the MiG-31B version, the aircraft has been equipped with the in-flight refuelling system.
Avionics.The RP-31 Zaslon phased array radar is the backbone of the weapons control system. The radar indicator in the operator’s cockpit displays multiple detected targets with ten of them being tracked automatically. The Argon-K integral computer chooses four most important targets with four R-33 air-to-air missiles guided to them. The 8TK infrared sensor under the fore part of the fuselage is an additional detection means. In flight, the IR sensor is retracted and in the operating position it is extended. The IR sensor is coupled with the radar and designed for passive surveillance of the airspace and target designation for the R-40TD and R-60 IR homing missiles. The cockpit accommodates the PPI-70V targeting and flying instrument. The automatic tactical data exchange between the aircraft of the group is performed through the APD-518 data transmission equipment. Guidance commands from ground command posts to the interceptor are transmitted via the 5U15K-11 integral command and control radio link equipment.
The flight and navigation equipment comprises the SAU-155MP automatic control system with the SOS-3M-2 limiting signal system and the KN-25 navigation set with two IS-1-72A inertial systems with the Manyovr digital computer, the Radikal-NP (A-312) short-range navigation, landing and relative coordinates system, the A-031 radio altimeter, the ARK-19 automatic radio compass, the A-611 marker radio receiver, and the Kvitok-2 A-723 radio long-range navigation system (in the MiG-31B aircraft). The long-range radio navigation is carried out within two systems – the Tropik system (the analogue of the LORAN system) with a range of 2,000km and coordinates’ accuracy varying from 130 to 1300 m and the Marshrut system (the analogue of the Omega system) with a range from 2,000 to 10,000 km and coordinates’ accuracy from 1,800 to 3,600 m. The communications equipment includes the R-800 and R-862 VHF/UHF radio sets and the R-864 HF radio set. The aircraft also features the SPO-15LM Beryoza radar warning receiver and the UV-3A passive countermeasures device.
Armament. The MiG-31 weapons suite consists of an integral cannon and air-to-air missiles. The main variant of the weapons mix is four R-33 long-range missiles set in pairs one after another under the fuselage on the AKU-410 catapult devices. Besides, two R-40TD medium-range missiles or four R-60M short-range IR homing missiles can be carried on the underwing hardpoints. The GSh-6-23M six-barrel 23 mm cannon is housed in the fairing on the starboard of the fuselage.
| Description | ||
|---|---|---|
| Design | OKB A.I.Mikoyan | |
| Type | MiG-31 | |
| NATO code name | Foxhound | |
| Function | long-range interceptor | |
| First flight | 6 september 1975 | |
| Crew | 2 | |
| Dimensions & Weight | ||
| Length, m | 22,688 | |
| Overall height, m | 6,15 | |
| Wing Span, m | 13,464 | |
| Wing Area, m2 | 61,6 | |
| Wheel base, m | 7,113 | |
| Wheel track, m | 3,638 | |
| Take-off weight, kg | max. (2 drop tank) | 46200 |
| normal | 41000 | |
| empty | 21825 | |
| Internal fuel, kg | 16350 | |
| Warload, kg | 4000 (3000) | |
| Power-plant | ||
| Engines | 2 Turbofan D-30F6 | |
| Thrust, kgf (kN) | max | 9500 (91) |
| in afterburner | 15510 (152) | |
| Performance | ||
| Radius of action, km | supersonic (M=2,35) | 720 |
| subsonic with drop tank | 1400 | |
| Range, km | operational | 2150 |
| ferry | 3300 | |
| Speed, km/h (M=) | max at ground level | 1500 |
| max at altitude 17500 m | 3000 (2,83) | |
| cruise | 2500 (2,35) | |
| Practical ceiling, m | 20600 | |
| Max g-load | 5 | |
| Take-off run, m | 950-1200 | |
| Landing run, m | 800 | |
| Armament | ||
| Cannon | GSh-6-23M six-barrel 23 mm | |
| Missiles AA | R-33 | 4 |
| R-60M | 4 | |
References and Credits:
- History and aircraft of Mikoyan design bureau / «Wings of Russia», 1999, CD-ROM /
- Aviatsia i Kosmonavtika №8.1999
- «Fighters» / V.Il’in, M.Levin, 1997 /