Armored Combat Vehicle [ACV]
An Armored Combat Vehicle [ACV] is a self-propelled vehicle with armored protection and cross-country capability. Armoured combat vehicles include armored personnel carriers, armored infantry fighting vehicles and heavy armament combat vehicles. The term "armored personnel carrier" [APC] means an armored combat vehicle which is designed and equipped to transport a combat infantry squad and which, as a rule, is armed with an integral or organic weapon of less than 20 millimeters calibre.
The term "armored infantry fighting vehicle" [AIFV] means an armored combat vehicle which is designed and equipped primarily to transport a combat infantry squad, which normally provides the capability for the troops to deliver fire from inside the vehicle under armored protection, and which is armed with an integral or organic cannon of at least 20 millimeters caliber and sometimes an antitank missile launcher. Armored infantry fighting vehicles serve as the principal weapon system of armored infantry or mechanised infantry or motorised infantry formations and units of ground forces.
The term "heavy armament combat vehicle" means an armored combat vehicle with an integral or organic direct fire gun of at least 75 millimetres calibre, weighing at least 6.0 metric tonnes unladen weight, which does not fall within the definitions of an armored personnel carrier, or an armored infantry fighting vehicle or a battle tank. The term "unladen weight" means the weight of a vehicle excluding the weight of ammunition; fuel, oil and lubricants; removable reactive armor; spare parts, tools and accessories; removable snorkelling equipment; and crew and their personal kit.
While tanks were employed by combatants in World War I, armored transport for foot soldiers did not become a reality until the eve of the Second World War. At that time, the German Wehrmacht and the US Army simultaneously developed the concept of mechanized infantry, and created armored personnel carriers (APC) to equip high-mobility units. As with its German counterpart, the American M3 "half-track" was a thinly-armored, open-topped vehicle. It provided protection from small arms fire and shrapnel, but the infantry squad remained vulnerable to shrapnel from air-bursts of artillery shells.
The mechanized infantry normally work as integral members of the “combined arms team” with armor. They travel in infantry fighting vehicles (IFVs) or armored personnel carriers (APCs) that enable them to keep up with the tanks. IFVs provide some ability to fire while on the move, but most of the squad dismounts to fight on the ground when assaulting or defending a position or clearing an area. Mechanized infantry therefore share many of the stressors of armor while having more logistical support (and logistical requirements) than other infantry.
Given the limitations inherent in its design, doctrine called for the APC would be employed as a "battle taxi." It gave troops a measure of protection en route to the objective, but the infantry were supposed to dismount to attack. In practice, infantry frequently declined to dismount in battle, preferring the [modest] protection of the truck. So in actual use, the half-track was often driven onto the objective, enabling nboard infantrymen to fight while mounted. Employed in this manner, the vehicle’s armament — typically a single, pintle-mounted, M2 .50-caliber heavy machine gun (HMG) — added greatly to the firepower of the squad. After World War II, a succession of full-tracked, armored personnel carriers — the M39, M44, M75, and M59 — were developed. None was a satisfactory response to Army requirements.
By 1960 the M113 APC [the "one-one-three"], with a hull of a special aluminum alloy, was light enough for parachute delivery, buoyant enough to swim without preparation, and tough enough to protect occupants from artillery shell fragments and rifle bullets. Troops are shielded from artillery air-bursts when the cargo hatch is shut on the fully-enclosed design (overcoming a significant weakness of the WWII half-track). The down side is that are unable to use their weapons until after they exit the vehicle, in keeping with the "battle taxi" concept.
Wartime practice overturned peacetime doctrine when the M113 was used in the Vietnam War. It did not take long for mechanized soldiers to realize that the APC was quite usable for mounted warfare; with the cargo hatch locked open, as many as four men could stand up in the opening to fire their rifles. Although they were then exposed to enemy fire, the risk seemed worth the benefits. The combat power of of the vehicle was tripled by installing pintle-mounted, 7.62mm machine guns on each side of the cargo hatch [the standard M113 had only a single .50-caliber HMG]. With armor shields added to the three machine guns, the gunners were well protected from small arms fire, and the configuration became known as the armored cavalry assault vehicle (ACAV).
While the ACAV performed capably in Southeast Asia, there was doubt that it would be adequate for high-intensity conflict. The ACAV conclusively proved the usefulness of mounted combat by the infantry, but it was also apparent that the exposed crew would be vulnerable to the nuclear, biological, or chemical (NBC) hazards in a war against the Warsaw Pact. In contrast, the Israeli Defense Force (IDF) apparently found the ACAV concept worthwhile. IDF armored personnel carriers were typically armed with three 7.62mm medium machine guns rather than the .50-caliber and two “seven-six-deuces” of the ACAV.
The M113’s minimal armor protection was easily defeated not only by the shaped-charge projectiles fired from recoilless rifles and hand-held antiarmor weapons like the RPG-7, but also by the bullets from 12.7mm and 14.5mm heavy machine guns. This happened numerous times in Vietnam, and to Israeli mechanized units in the Middle East. The IDF attempted to cope with this by attaching additional armor to many of their M113s. This reduced the severity of the problem, but did not eliminate it.
By 1963 US Army leaders recognized the limitations of the M113, and initiated a quest for a replacement. Nearly two decades later, after some false starts, budgetary difficulties, and program delays, the M2 Bradley infantry fighting vehicle (IFV) was born. In its original incarnation, the Bradley offered four major improvements over the armored personnel carrier: increased armor protection, superior cross-country mobility, greater vehicle firepower, and the capability for mounted combat by all of the onboard infantrymen. This last characteristic was fundamental to the IFV concept as developed by Russia, Germany, and the United States, for it allowed the infantrymen in the M2 (and M2A1) to fight from within the vehicle, under armor.
The Army later abandoned the concept of fighting mounted when it added, on the newer M2A2 and M3A2 vehicles, steel applique armor on the turret and hull, with extended side skirts that block the firing ports on the left and right sides. Apparently, the increased level of protection was deemed more important than the infantryman’s ability to fight from within the vehicle. This course of action seems to actually reduce survivability.
Squads and platoons move mounted whenever possible. This conserves the infantryman's energy and takes advantage of the APC's mobility and armor protection. When the infantry dismounts, the dismount team must do so rapidly. Both dismount and carrier teams must be able to react with little or no instruction from the squad leader.
The dismount team moves 20 to 30 meters away from the vehicle in the direction specified in the dismount alert (left, right, or rear). The men immediately hit the ground using the best cover and concealment available and face outward toward the enemy. As soon as the dismount team leader accounts for every man and gets oriented, he gives instructions for movement to accomplish the team's mission or to link up with the other dismount teams to form the dismount element.
Whether in contact with the enemy or not, the platoon leader makes every effort to dismount in a covered and concealed location. It may be possible to deploy the dismount teams without the enemy detecting the dismount. This adds to the dismount team's security and lessens the chance they will be engaged by surprise fire.
The notion that IFVs only need sufficient gun and armor to do battle with enemy infantry vehicles seems to ignore the lessons of history. As long as they have enough ammunition and time available, tankers have a strong tendency to shoot anything that can be considered a legitimate target, and that certainly includes IFVs. During Desert Storm, for example, 1st Armored Division tankers readily destroyed the many Iraqi BMPs that came into their sights,18 and there was at least one Bradley gunner who was forced by circumstances to use his 25mm gun to engage a T-55 tank.
A combined arms tank (CAT) would carry an infantry fire team, but with the combat capability and survivability of the main battle tank. So far, the closest thing to a CAT in the real world is the Israeli Merkava, an MBT that has sufficient internal space to transport a few foot soldiers, and a rear hatch that makes ingress/ egress practical when under fire. While the Merkava was not designed expressly to be an infantry-carrying tank, it has been pressed into service in that role during some of the fiercest battles in Lebanon. the vehicles, in most cases the tank crews.
It is a dictum of modern war that armor and infantry be employed as a team in battle. Infantrymen and tanks provide mutual support and protection. Tanks without accompanying infantry are vulnerable to enemy tank-killer weapons; infantry without accompanying tanks is vulnerable to small arms, machine guns and other direct-fire weapons. Infantrymen protect the tanks from the tank killers and the tanks engage enemy direct-fire weapons. Armor offensive tactics also envision armor employed in large formations, en masse, to overwhelm an enemy and make deep penetrations.