Mechanized infantry

Mechanized infantry are infantry units equipped with armored personnel carriers (APCs) or infantry fighting vehicles (IFVs) for transport and combat (see also armoured corps). As defined by the United States Army, mechanized infantry is distinguished from motorized infantry in that its vehicles provide a degree of armor protection and armament for use in combat, whereas motorized infantry are provided with "soft-skinned" wheeled vehicles for transportation only. Most APCs and IFVs are fully tracked or are all-wheel drive vehicles (6×6 or 8×8), for mobility across rough ground. Some militaries distinguish between mechanized and armored (or armoured) infantry, designating troops carried by APCs as mechanized and those in IFVs as armored. The support weapons for mechanized infantry are also provided with motorized transport, or they are built directly into combat vehicles to keep pace with the mechanized infantry in combat. For units equipped with most types of APC or any type of IFV, fire support weapons, such as machine guns, autocannons, small-bore direct-fire howitzers, and anti-tank guided missiles are often mounted directly on the infantry's own transport vehicles. Compared with "light" truck-mobile infantry, mechanized infantry can maintain rapid tactical movement and, if mounted in IFVs, have more integral firepower. They require more combat supplies (ammunition and especially fuel) and ordnance supplies (spare vehicle components), and a comparatively larger proportion of manpower is required to crew and maintain the vehicles. For example, most APCs mount a section of seven or eight infantrymen but have a crew of two. Most IFVs carry only six or seven infantry but require a crew of three. To be effective in the field, mechanized units also require many mechanics, with specialized maintenance and recovery vehicles and equipment.