Infantry fighting vehicles

An infantry fighting vehicle (IFV), or mechanized infantry combat vehicle (MICV), is a type of armoured fighting vehicle used to carry infantry into battle and provide direct fire support. The Treaty on Conventional Armed Forces in Europe defines an infantry fighting vehicle as "an armoured combat vehicle which is designed and equipped primarily to transport a combat infantry squad, which is armed with an integral or organic cannon of at least 20 millimeters calibre and sometimes an antitank missile launcher."

Infantry fighting vehicles are distinct from armoured personnel carriers (APCs), which are transport vehicles armed only for self-defense and not specifically engineered to fight on their own. Consequently, IFVs possess heavier armament than an APC, and the attached rifle squad fights from within the vehicle more often than in an APC. IFVs also often have improved armour and some have ports which allow the infantry to fire personal weapons while on board.

They are typically armed with a 20 to 40 mm caliber , a coaxial machine gun and sometimes anti-tank guided missiles (ATGMs). IFVs are usually tracked, but there are some wheeled vehicles too. IFVs are much less heavily armed and protected than main battle tanks, but when equipped with larger cannon or ATGMs may pose a significant threat to all but the heaviest armoured fighting vehicles.

The first mass-produced IFV was the West German Schützenpanzer 12-3 which served in the Bundeswehr from 1958 until the early 1980s. The SPz 12-3 mounted a 20 mm autocannon in a small turret and carried a half-squad of five armoured infantrymen.

Western powers were surprised when the Soviet Union paraded the BMP-1, in 1967. The BMP possessed a very low profile and was armed with both a 73 mm smoothbore gun and an AT-3 Sagger ATGM, making it the first combat vehicle with mounted cannon and missiles in addition to a mounted infantry squad. Its steeply-sloped front armour offered full protection against NATO's standard .50 calibre machine gun and partial protection against a 20mm Oerlikon autocannon both in a 60 degree frontal arc, while its armament posed a threat to lighter NATO APCs and even main battle tanks. Soviet infantrymen could thus enter a hypothetical engagement in a vehicle that possessed formidable fighting capability in its own right. This brought combined arms integration to the lowest tactical level.

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