R-37 (K-37, Izdeliye 610)

The Vympel R-37 (NATO reporting name: AA-13 Axehead) is a Russian long-range air-to-air missile developed by the Vympel State Machine-Building Design Bureau. Designed primarily to engage high-value targets such as AWACS, tankers, and other C4ISTAR aircraft, it allows the launching platform to remain outside the range of escorting fighters. The R-37 was developed from the earlier R-33 (AA-9 Amos) missile, primarily for the MiG-31 interceptor, but has since been adapted for other platforms.

The R-37 program began in 1983 under the Soviet Union to create a long-range air-to-air missile (designated K-37, izdeliye 610) to replace the R-33 for the MiG-31M interceptor. The goal was to develop a missile capable of engaging targets at extended ranges, leveraging the MiG-31’s powerful radar. Development faced delays due to the Soviet Union's collapse, particularly because of disrupted cooperation with Ukrainian enterprises involved in the missile’s guidance systems. By 1997, Russia shifted to using only domestic components, leading to the modernized K-37M (R-37M). The missile was tested extensively, with a notable 1994 trial achieving a target hit at 304 km, and entered service in the 2010s.

The Vympel R-37 was designed to have a range of 300 km using a lofted trajectory and a maximum speed of Mach 6.

The usage tactic of this missile is to stay below the radar horizon of the AWACS with external radar support for target acquisition. With the range well estimated, the aircraft accelerates towards the target and climbs to maximize the missile's energy. The range increases to 350 km, appearing at the limit of the AWACS' range and then returns to hide again on the horizon. The missile is not detected during the climb and then dives. At 40-60 km, the missile turns on the sensor until it acquires the target, still diving at supersonic speed. The platforms do not have much time to react by maneuvering or evading. The tactic is difficult to counter due to the distance and speed of the aircraft and missile. The only warning may be the radar warning 30-40 seconds before impact. The reaction of the surveillance platforms will be the use of internal or external electronic interference systems, chaff and disposable towed jammers.

The base R-37 was not adopted for widespread service by the Russian Air Force, as focus shifted to the modernized R-37M. It was primarily a developmental platform.

More information:

• Wikipedia: R-37 (missile)
• Missilery.info: R-37 long-range aircraft missile (RVV-BD)
• GlobalSecurity: AA-13 ARROW / K-37/R-37 / RVV-BD
• Indian Defence Industries - R37M
• Military History Wiki R-37 (missile)
• TopWar.ru - R-37M long-range air-to-air missiles in Special Operations
• EurAsian Times - MiG-31 & Vympel R-37M
• Sistemas de Armas - R-37 (AA-13 ARROW)