Mechanized Infantry

Mechanized Infantry is a type of Ground force that combines Infantry with some form of Armored vehicles whose primary purpose is to provide heavy fire support. The vehicles in a Mechanized Infantry unit may include heavily-armed APCs, IFVs, Tank Destroyers or even Tanks. All units in a Mechanized Infantry force are subordinated to the same Command Structure, which is responsible for coordinating their actions in support of one another.

While Infantry units in a Mechanized Infantry force are generally organized in the same way as any other Infantry, each vehicle has its own dedicated crew (Driver, Gunner and/or Vehicle Commander) who are not generally expected to dismount from their vehicle unless it is damaged beyond use. The vehicles are typically split into Vehicle Sections, which can be moved around the combat area to support whichever front is the most vulnerable to heavy enemy attack at any given time. The Infantry and vehicles usually move together, covering each other to effectively tackle any kind of threat they might face. Vehicles may temporarily be attached to a specific Squad to provide it with close support, but will more often remain flexible in their deployment. The Infantry is only rarely ordered to use the vehicles for transportation, if at all.

The types of vehicles used in Mechanized Infantry are heavily armed and armored compared to Motorized Infantry. IFVs are the most common in this role, as they are sufficiently armed to engage and destroy enemy heavy vehicles of all types, while also being largely impervious to enemy Small Arms fire. APCs are rarer in this role, as most models lack both weapons and armor. Tanks can also be used in Mechanized Infantry forces, providing less assistance against Enemy Infantry but more against heavy vehicles. Most vehicles in a Mechanized role are heavy enough to operate on their own when necessary, but will generally stick close to infantry to enjoy more protection against foot-mobile Anti-Tank Launchers.

Player-controlled Mechanized Infantry forces are rarer in ShackTac missions than pure Infantry or even Motorized Infantry. Scenarios involving Mechanized Infantry are typically offensive - attacking one or more objectives - and often involve a larger number of enemy heavy vehicles to challenge the friendly vehicles.

Concept
The origins of Mechanized Infantry can be traced all the way back to World War I, with Infantry hopping onto early Tanks for safe transportation across the battlefield, or following them closely in light Trucks. However, originally this combination was mostly impromptu, with no over-arching military doctrine or organization. After the war, with Tanks becoming ever more mobile, Motorized Infantry was incorporated directly into tank units: Trucks and light APCs were used to move infantry alongside tanks, providing the tanks with additional protection against enemy infantry attacks and providing the infantry some measure of protection while on the move. This method was perfected by the Germans for their "Lightning War" ("Blitzkrieg"), allowing such combined forces to attack and advance very quickly - encircling enemy positions and exploiting gaps in the enemy's defense. Other armies were not far behind in adopting these tactics.

Mechanized Infantry continued to develop during World War II, especially as APCs became better armored and started carrying heavier support weapons. However true Mechanized Infantry - more closely resembling the kind used in ShackTac - only emerged with the development of the Infantry Fighting Vehicle. A heavy transport vehicle with tank-like weapons and sufficient armor to protect its passengers against heavier attacks made it possible for infantry to ride into combat inside the vehicle, and then dismount to fight alongside it using combined-arms tactics.

Modern IFVs are exceptionally dangerous to both Infantry and enemy Armor. So long as friendly infantry are there to protect them against Anti-Tank Launchers, the IFVs can tackle pretty much any threat, including even Tanks and Helicopters. However the IFV suffers from the same vulnerabilities as most heavy vehicles do - a tunnel vision that makes it difficult to tackle multiple threats simultaneously. This means that the IFV becomes ineffective - or even endangered - when it strays away from its friendly infantry. It is the coordination between the IFV and its infantry that allows them to protect each other and multiply their power against enemy threats.

As a result, the units will move together at all times, often keeping a line formation where both types of units can engage enemies simultaneously. Infantry may move forward of the IFV to clear forests or urban areas where the vehicle would be more vulnerable; The IFV will rarely drive forward alone. In some cases, the IFV may take up a position overwatching friendly infantry as they advance, if it can find a position that has a good field of view over possible enemy approach vectors. As soon as the IFV becomes unable to protect the infantry, it will typically be moved up.

Both APCs and Tanks can serve in the same role as an IFV, with differences based on their armor and weapons. APCs have much less armor than an IFV, and must remain closer to the infantry at all times. They also have much less firepower against enemy armor, and will mostly assist with destroying enemy Infantry, APCs or other light vehicles, withdrawing quickly whenever a heavier enemy vehicle appears. Tanks, on the other hand, will mostly assist against enemy armor; They tend to take overwatching positions more frequently, to destroy incoming armor well before it can threaten friendly infantry.

Vehicle Types
The vast majority of vehicles used for player-controlled Mechanized Infantry in ShackTac are Infantry Fighting Vehicles. These vehicles have a good amount of armor (usually capable of surviving at least one hit from a Light Anti-Tank Launcher) as well as a heavy weapon of some sort. These are generally tracked vehicles, and also have the capability of carrying at least a Fireteam of friendly infantry as passengers.

Alternatively, both Armored Personnel Carriers and Tanks may serve as part of a Mechanized Infantry force - whether instead of or additionally to IFVs - with Tanks being slightly more common. Enemy forces encountered during the mission will often match this - with more light/medium vehicles attacking an APC-equipped force, or more IFVs and Tanks attacking a Tank-equipped force.

Note that these vehicles are occasionally encountered as their own, separate units (Vehicle Platoons or Tank Platoons) which are not strictly considered "Mechanized Infantry" due to the way they interact (or rather, don't interact) with friendly Infantry forces. The main difference is in organization, as explained in the following chapter.

Vehicle Weapons
Vehicles used in Mechanized Infantry typically carry at least one of the following weapons:


 * Heavy Machine Gun: An effective weapon for destroying Enemy Infantry. Also capable of destroying Trucks, Recon Cars, Armored Cars or with some luck even APCs. Helicopters are also somewhat threatened by HMGs. Many Mechanized Infantry vehicles carry an HMG as their secondary weapon; It is rarely powerful enough to be used as a primary weapon for such heavy vehicles.
 * Rotary Gun: A multi-barreled Machine Gun that fires bullets at an extremely high rate. Though the bullets are generally lighter than those of an HMG, the high rate of fire allows much better effect against Infantry and light vehicles, and stands a good chance of striking the vulnerable systems of a heavier target or rendering it immobile. This weapon is largely ineffective against Tanks, and may struggle to have any effect on IFVs. It can, however, shoot down aircraft rather effectively.
 * Autocannon: The most common primary weapon of IFVs, an Autocannon fires 20-30mm shells at a high rate. The shells can be Armor Piercing or High Explosive, and most vehicles can switch between these two types. Autocannons are very dangerous against any type of target, though they require some luck to defeat an enemy Tank.
 * Anti-Tank Guided Missile: Mostly carried by IFVs and some specific types of APCs, this guided missile poses a great danger to any enemy armored vehicle. Manually-guided in flight, an ATGM can track a target from a very long distance away, and is likely to destroy any target on impact. Skilled gunners can even use them to shoot down Helicopters. ATGMs are not effective against infantry, and come in very short supply.
 * Cannon: Tanks as well as some IFVs carry a cannon that fires heavy shells designed to penetrate enemy armor. A single hit is often enough to destroy any vehicle. Though High Explosive shells do exist, and can effectively destroy infantry, cannons are typically loaded with Armor Piercing shells to tackle enemy armored threats. Skilled gunners can take out Helicopters with this weapon as well, but the low rate of fire of a Cannon compared to an Autocannon makes this less of a viable option.
 * Automatic Grenade System: As its name implies, this weapon fires bursts of explosive grenades at a high rate. It can blanket an area with explosions, potentially destroying large clusters of enemy infantry. An AGS is also very dangerous against soft-skinned and lightly-armored vehicles. Repeated hits against armor can knock out subsystems or render a heavy vehicle immobile.
 * Surface-to-Air Missile: A few IFV models like the Linebacker are armed with a number of SAMs, which can track and destroy enemy Aircraft. This is a very effective weapon against such threats, but cannot be used against ground targets at all.

Organization
Mechanized Infantry is organized differently from either Motorized Infantry or a dedicated Armor force. In a Mechanized Infantry force, the Infantry is organized exactly the same as in pure Infantry Platoons, while the vehicles are assigned to separate Vehicle Platoons or Vehicle Sections which are subordinated to the same Command Structure. This allows the vehicles to operate independently of the Infantry, while maintaining a close coordination with the movements and disposition of the infantry force.

Each vehicle in a Mechanized Infantry force has its own Gunner, Driver and Vehicle Commander. Some vehicles only require two crewmembers, in which case the Gunner or Driver will also serve as a Commander. These players remain inside the vehicle so long as it is operational, and will only exit it for specific reasons such as observing the area or communicating with another nearby unit off the radio. These players are grouped together as a single unit, including its own Map Marker and Callsign. They are not expected to fight on foot under any circumstances other than if their vehicle is disabled or destroyed.

Mechanized vehicles are often given the callsign "Mike" (for "M", or "Mechanized"), followed by a number - e.g. "Mike One", "Mike Two", etc. The number is mostly just for identification, but may also indicate seniority on the chain of command, with Mike One having slightly greater authority over the other vehicles. The callsign "Sierra" may be used instead for lighter vehicles such as APCs, which require closer coordination with the infantry. Callsigns other than "Mike" and "Sierra" are occasionally used instead, especially for OPFOR units, and may include "Sickle", "Hammer", or others.

Vehicles may or may not be grouped together into Vehicle Sections or Vehicle Platoons, depending on the mission parameters. Vehicles are rather effective when fighting in pairs or groups, but if there are not enough vehicles in the mission to warrant this type of behavior, they'll be kept separate. In a Vehicle Section or Platoon, one of the vehicles (usu. "Mike One") will typically be assigned as a Leader, with its Commander coordinating the actions of all other vehicles of the same callsign. Otherwise, all vehicles are directly subordinated to the Infantry's Command, whether it is a Platoon Leader or Company Commander.

Mechanized vehicles may or may not have their own 148/152 long-range radio channel to converse with each other. They also listen to Platoon Net or Company Net for orders, and may transmit reports on that channel like Infantry Squad Leaders do. On these channels, the vehicles may be referred to collectively as "Vics", "Sierras" or "Mikes", as appropriate.

In cases where a vehicle or Vehicle Section needs to coordinate closely with one of the Infantry Squads, it may temporarily switch its 343 short-range radio to that Squad's channel. This allows the vehicle to keep track of the Squad's actions and movements, report targets to them, and receive targeting information from them. This coordination allows the vehicle to use the infantry as scouts, and can easily save a vehicle from destruction in case enemy infantry show up with Anti-Tank Launchers in close proximity. It can also more easily move together with the infantry, or move to defend them from a different angle if they spot a new batch of targets. The Infantry unit's Squad Leader may have slightly increased authority over the vehicle in such cases, since he typically has a better tactical understanding of the situation than both the vehicle's own commander and any other higher-level commanding officer.

Typical Structure
Mechanized Infantry Platoons and Companies can be structured in one of two primary ways: With the vehicles directly subordinated to the Squads, or with the vehicles directly subordinated to Command. The size of the ground force further determines who the vehicles are subordinated to.

Integrated Vehicles
In the "Integrated Vehicles" setup, each heavy vehicle or Vehicle Section is assigned to one specific Squad in the platoon. The vehicle is responsible for providing both fire support and transportation to the Squad it is assigned to.

This setup is more commonly used with APCs and light IFVs, as they often require close mutual support from the infantry to survive, reducing their autonomy. Such vehicles are usually very vulnerable to enemy Anti-Tank Launchers, IFVs and Tanks, often relying on the infantry to handle those threats.

Vehicles in this setup typically receive a callsign that starts with the name of the Squad they are assigned to support, followed by the word "Victor" (for "Vehicle") -- e.g. "Alpha Victor", "Bravo Victor" and so on. The vehicle's icon may be colored the same as the Squad's icons too.

Platoon-Level Flexible
In the Platoon-level "Flexible" setup, the heavy vehicles are considered a separate element to the infantry, and report directly to a Platoon Leader. The PLT will either order the vehicles around to support different Squads as necessary throughout the mission, or keep them as a cohesive Vehicle Section that is escorted by infantry on both flanks.

This setup is more suitable for heavier IFVs or even Tanks. Each vehicle is capable of significantly bolstering the firepower of any squad that needs its help, whether to defend a strong position, assault an enemy strongpoint, clear a road ahead, etc. The vehicles are tough and powerful enough that they do not always need close support from infantry, especially on open terrain.

Company-Level Flexible
This setup is unique to Company-level operations, which are rare to begin with. In it, an entire Tank Platoon, IFV platoon or mixed platoon is subordinated to the Company Commander, and is typically used as a powerful base of fire to support an Infantry Platoon's advance. The vehicles generally stick together as a single unit, covering the infantry from a commanding position as they advance. They may temporarily split up into pairs to cover a larger area (or multiple directions) as necessary.

The Company Commander has full discretion on repositioning the vehicle platoon to support any infantry unit as necessary, but the vehicles also have their own Platoon Leader who handles detailed tactical decisions. In this setup, the vehicle Platoon Leader role is normally given to the Vehicle Commander of the first vehicle in the platoon.

Mikes vs. Sierras
The two most common callsigns for Mechanized Infantry vehicles are "Mike" and "Sierra". The distinction between these is not simply cosmetic - it also quickly identifies the class of vehicle being used, and thus the best manner in which it should be used in conjunction with the infantry.

"Sierras" are "support" vehicles, typically heavy APCs or even Armored Cars. These vehicles are more vulnerable and/or carry somewhat lighter weapons. As a result, they are often used in very close proximity to the Infantry, and will rarely stray far from their side. In many cases, each Sierra or pair of Sierras might be assigned to a specific Squad, following them throughout the entire mission. Sierras are also typically faster vehicles, and are more likely to be used for transporting infantry from one position to another (though this is still somewhat rare). Due to the close coordination with infantry, it is more common to hear Sierras switching their radios over to the channel of a nearby Squad.

"Mikes" are true "Mechanized" vehicles, typically IFVs or even Tanks. Their heavy armor and heavy weapons allow them to behave more independently, often taking up positions further away from the infantry, or allowing the infantry to advance well forward of their position while the "Mike" watches over them from a commanding position. A Mike is also more likely to switch firing positions to tackle threats coming from different directions, assisting multiple different Squads during the course of a mission. Mikes are rarely if ever used to transport Infantry, if they can carry infantry at all.

Logistics and Engineering
Mechanized Infantry forces are much more likely to have a dedicated Logistics unit on the ground with them. This unit - called "Logi" - is responsible both for bringing ammunition to the infantry and vehicles, and for repairing the vehicles if they get damaged. In some ShackTac missions (particularly during the ArmA 2 era) a second Engineering unit is added specifically to provide repairs, while Logi handles resupply only.

Logi travels around in Trucks, allowing them to quickly cover a lot of ground, resupplying and maintaining an entire force spread out over a large area. In a Mechanized Infantry force, one truck is dedicated to rearming the heavy vehicles. It is necessary to park the truck right next to the vehicle, and then perform a special action to refill the vehicle's weapon with ammunition. There is no other way to resupply a vehicle. If the ammunition truck is lost, vehicles may be rendered unusable if they run out of ammunition (though they can still be used for transportation, where applicable). For this reason, additional ammunition trucks may be spawned back at base, if the Game Master (and the situation) allows this.

Repairing a damaged vehicle may or may not be possible, depending on the mission's configuration. In some missions, Vehicle Crews can repair their own vehicles to some extent. In others, only members of the Logistics/Engineering unit can do so. In yet other missions, a special repair vehicle is brought along by the Engineering or Logistics unit, and must be parked next to the damaged vehicle to repair it (same as rearming a vehicle, as explained above). In order to repair a vehicle, it must not be fully destroyed.

Tactics
A Mechanized Infantry force behaves, for the most part, similarly to a regular Infantry force; However the addition of heavy vehicles allows it to exert more firepower at specific points along the line, allowing for sudden powerful attacks or much strong defensive action. The vehicles also provide the potential for fast and relatively safe movement across longer distances, though this is only capitalized on in very particular situations.

Positioning and Movement
The position of Mechanized Infantry vehicles relative to the Infantry force follows a certain pattern depending on the type of vehicles present, the objectives of the mission, and the terrain itself. The mutual movement of infantry and vehicles to provide fire support and assistance to one another - if performed correctly - is what makes a Mechanized force so effective.

Lighter vehicles (usu. given the callsign "Sierra") typically remain very close to the infantry. The vehicle uses its support weapon to attack the same targets the infantry does - only more effectively. Even in wide-open spaces, the vehicle will rarely travel far from the infantry. Failure to keep up with the infantry can expose the vehicle to enemy fire, which can often cause its destruction.

Heavier vehicles, especially tanks, tend to keep a certain distance away from infantry. The vehicle usually chooses a path through more open terrain, giving it a wide field of view. This allows the vehicle to spot targets from further away, using its heavy weapon to engage them safely before they can pose a threat either to itself or to the infantry. Friendly infantry then "shadows" the vehicle on one or both sides, moving through forests or urban areas on the vehicle's flanks to clear them of possible threats. This sort of movement allows the vehicle to watch out for larger targets and provide fire support against enemy infantry, while making sure that enemy infantry with Anti-Tank Launchers can't come close enough to threaten it.

In places where this sort of wide-front movement is not possible (and especially when the vehicles move in a convoy along a road), the infantry typically screen the force by Taking Point, with the vehicles advancing closely behind them. The vehicles may stop at the head of a long stretch of road, to defend that road against possible enemy vehicles coming in the other direction, while the infantry sweep forward for enemy infantry ambushes. If a heavy target is encountered, the vehicles can move up to engage it while the infantry stop and hold the flanks.

Mounting
Most vehicles used in Mechanized Infantry are capable of carrying a number of passengers, typically a Fireteam or even a whole Squad. Nevertheless, this ability is rather rarely used in ShackTac except in very specific circumstances.

Armored vehicles can be used to tactically reposition an Infantry unit in a hurry. This is done when the infantry are urgently needed elsewhere, or have been left a significant distance behind the rest of the force. Instead of forcing them to march over a long distance to their new position, a nearby vehicle is sent to pick up the unit and ferry them over. This is easily the most common way Mechanized Infantry vehicles are used, when they are used at all. Because the journey is typically short and quick, BMPs (and occasionally Soviet-model Tanks) with slots for passengers riding on the hull may load passengers in those slots - something which is typically seen as excessively dangerous for long-distance travel.

A more uncommon use of armored vehicles for transport is Insertion, with the vehicles driving in a Convoy along a road towards their intended dismount point. Since this poses a serious risk to the infantry inside the vehicles, they will typically dismount as soon as any enemy opposition is encountered, and will rarely re-mount the vehicles again for the rest of the mission.

If a sufficient number of vehicles remains usable at the end of the mission, they can be used for a quick Extract. This is significantly faster than walking out of the combat zone, but the long journey inside the vehicle risks a sudden enemy anti-tank ambush that could kill the vehicle and its occupants in a single hit. The infantry may be forced to dismount if enemies are encountered along the way.

Notable Examples
Mechanized Infantry is fairly common in ShackTac. There is no need to mention every single occurrence of this type of setup. Instead, please include only "textbook" examples, as well as examples of deviations from the normal structure/rules outlined above.


 *  by Dslyecxi: Unusually for a Mechanized Infantry scenario, this mission starts with both the infantry and their APCs (BTR-90s) being air-dropped in by Transport Helicopters and Transport Planes. Multiple UAZs are dropped in as well, but the video shows that only Platoon HQ actually took one - with the Squads riding in (and on) the BTRs for transportation. The platoon is organized according to the "Integrated Vehicles" setup, with one APC per Squad. The initial lack of a Logistics unit quickly becomes a problem when two of the BTRs lose their wheels on the way to the second objective. The damaged BTRs are left behind, and later two BMDs are air-dropped in to replace them, along with a Logistics vehicle for an impromptu Logi team.


 *  by Dslyecxi: Features a mixed Integrated/Platoon-Flexible setup, with BMPs as "Mikes" and BTR-80s as Squad Vehicles. In the case of Charlie Squad, led by Dslyecxi in this video, the initial push was supported by one of each - both of whom switched to Charlie's 343 channel to coordinate with the Squad during the advance.