Notes: The original design for what was then known as the LVTP-7 dates back to the mid-1960s and the Vietnam War. First operational units reached the US Marines in 1971, and were then armed with a small cupola and an M-2HB machinegun. In 1986, upgrades began to replace that cupola with a larger turret armed with a Mk 19 grenade machinegun and the original M-2HB. There are two large hatches on the rear deck, and a power ramp in the rear with a door in it.

Notes: This is the next generation of amphibious assault vehicles, designed for the US Marines. The AAAV has heavier armor than the AAPV-7A1, consisting of welded aluminum alloy backed by ceramic and a Kevlar anti-spall liner. The AAAV is fully amphibious, capable of full off-road speed in water. The AAAV is not expected to begin equipping US Marine units until late 2013.

Twilight 2000 Notes: This vehicle does not exist.

Notes: Though development of what would become the AAVP-7 began in 1964, it was the first year of US involvement in Vietnam that really brought home to the Marines the shortcomings of the LVTP-5 series and the need for a better amphibious APC. The Marines quickly discovered that the LVTP-5 had a number of problems – it’s torsioelastic suspension, while it provided a comfortable ride over water and shore conditions such as rocks, sand, and reefs, was ill-suited for long trips and thus subject to frequent breakdowns. The LVTP-5 used the transmission and engine of the M-48 main battle tank – great for power, but not suited in the LVTP-5’s configuration; it could take a day of more to replace the power pack, and even routine service could require pulling out large amounts of the power pack just to get to the components to be serviced. Perhaps the greatest problem with the LVTP-5 as used in Vietnam lay with the fuel system; the tanks were under the floor, the engine ran on gasoline, and as the entire vehicle was lightly armored in the first place, even an antipersonnel mine explosion could sometimes turn the interior into a fiery slice of hell.

Because many of the LVTP’s problems were caused by improper employment of the vehicle, the Marines wanted something new that could take on roles Amtracs of the past could not. One of the first things to go was the torsioelastic suspension, replaced with a conventional torsion bar suspension on what was then called the LVTP-7 (later changed to AAVP-7). The armor protection was considerably upgrade, using the same 5083 aluminum armor that was used on the M-113 series. The engine chosen was a supercharged 400-horsepower 8V53T diesel truck engine with an HS-400 transmission; more importantly, the powerpack was a unified unit that could easily be lifted out of the vehicle in a matter of minutes with the proper equipment. The transmission was semiautomatic – it required no clutch, but still required gear selection on the part of the driver. The tracks were almost 54 centimeters wide for traction on soft sand as well as marshy conditions, and water propulsion was provided by two waterjets at the rear. Many other ideas were added, thrown out, or modified, and that, combined with political wrangling, meant that first deliveries of the LVTP-7 did not occur until 1972.

The LVTP-7 has a 3-man crew (driver, assistant driver, commander), and seated 25 Marines in the passenger compartment in the rear. The driver’s position is in the left front of the hull, behind the engine compartment, with the commander’s cupola behind and to the right of the driver. The assistant driver is on the opposite side of the hull from the driver, with a second set of driving controls. The officer or NCO in charge of the Marines in the rear has his own cupola to the rear of the driver’s hatch. The driver’s position as well as the OIC/NCOIC cupolas have seven periscopic vision block, and the commander’s cupola has nine; the front vision blocks at each position can be removed and replaced with an infrared night periscope. (There is no such provision at the assistant driver’s position.) In the rear ramp is a further vision block. In the passenger compartment, the remaining 24 Marines are seated in three rows of eight; all of the seats can be stowed away, clearing the compartment for cargo. The fuel tanks are in the walls of the vehicle. The commander’s cupola of the prototypes was armed with a 20mm M-139 autocannon and an M-73E1 7.62mm machinegun. The production versions, however, replaced these weapons with a single M-85 heavy machinegun with an 8x optical sight in a smaller cupola. An attempt was made on the prototypes to provide firing ports for the passengers, but these could not be squared with the need to maintain the watertight integrity of the hull. The rear deck has two large hatches, and the rear has a ramp with a door in it.

APC variants of the basic LVTP-7 include the LVTC-7 Command Vehicle. This version has provisions for up to seven radio antennas and a plethora of radios and communications equipment. The driver, assistant driver, and vehicle commander’s position are retained, but the cupola for the Marine troop commander is deleted and covered with an armored cap that is bolted on (though the vision blocks remain in place). As with the LVTP-7, the LVTC-7 vehicle commander’s cupola had a single M-85 machinegun, but in later production this cupola was unarmed so that other equipment could be stowed in the places that once held ammunition. In addition to the vehicle crew, the modified rear passenger area has a standard crew of one unit commander, four staff personnel, and five Marines to operate the communications equipment, assist the command staff, and perform other duties. There is a bench seat on the right side for these five crewmen; there is also a sliding mapboard and the communications equipment at this station. Various drawers, a folding table, and other ancillary equipment are also provided. Additional seats are found at the former troop commander’s position, at the front next to the unit commander’s seat, and at the rear of the vehicle.

Though the Marines expected to have the LVTP-7’s successor operational by the mid-1990s, delays, funding difficulties, and continuing research on the LVTP’s replacement considerably delayed its replacement (the ERV, which hasn’t yet been fielded). Therefore, in the early 1980s, a SLEP (Service Life Extension Program) was started, turning the LVTP-7 into the LVTP-7A1. This SLEP included replacement of the power pack and suspension, a new communications system based around the SINCGARS radio, upgraded protection, and a general overhaul of the vehicle. The engine was replaced by a 400-horsepower VT400 multi-fuel engine and a modified form of the old transmission called the HS400-3A1. The commander’s cupola was given an electric drive and the cupola enlarged slightly into a small turret with slightly-increased armor protection, along with eight smoke grenade dischargers. The shock absorbers were considerably upgraded, and shock absorbers were installed on the second set of roadwheels (where there had previously been none). Fuel tanks were replaced by flexible fuel bladders contained within the vehicle walls; these bladders are a bit further out from the passenger compartment walls and have self-sealing ability. The LVTP-7A1 was given the ability to lay a smoke screen by injecting diesel fuel into its exhaust. The assistant driver was given a night vision periscope. The bilge pumping system was given considerably more power. The LVTC-7 was given the same improvements and became the LVTC-7A1 (with the exception of the commander’s weapon station).

In 1984, during a vehicle and equipment designation change that affected many vehicles and equipment, the LVTP-7A1 was redesignated the AAVP-7A1. Any older LVTP-7s still in existence were redesignated AAVP-7. The LVTC-7 and LVTC-7A1 were redesignated AAVC-7 and AAVC-7A1 respectively. At this point, the commander’s weapon stations were replaced with small turrets equipped with both an M-2HB heavy machinegun and a 40mm Mk 19 automatic grenade launcher. Appliqué armor packages (designed by Rafael of Israel) were also devised for the AAVP-7 series, along with lugs for ERA; in addition, a steel mesh-type appliqué armor kit has been deployed on the AAVP-7A1. The bow plane was also modified to compensate for the weight and unbalancing effect of the appliqué armor when the AAVP-7A1 series is swimming.

Some interesting firepower upgrades were proposed for the AAVP-7A1. One of these was to replace the heavy machinegun with a 25mm M-242 Bushmaster autocannon, along with enlarging the turret. Another one (apparently seriously looked at) was to mount the turret of an M-2 Bradley on the AAVP-7A1. I have some stats for these below, but they never actually went past the conceptual phase.

The LVTP-7 and its descendants are typically called "Amtracs" or less commonly, "Gators" by their crews. Italy’s San Marcos Marines, Taiwan, Thailand, and Argentina are also known users of the LVTP-7 series.

Twilight 2000 Notes: In the Twilight 2000 timeline, virtually all of these vehicles are up to the AAVP/AAVC-7A1 standard in US use. Some other countries using them (such as Taiwan, Thailand, and Argentina) are using primarily LVTP/LVTC-7A1s and some LVTP/LVTC-7s. Some older LVTP-7s and LVTP-7A1s were refurbished early in the Twilight War and brought up to AAVP/AAVC-7A1 standards, but every so often (primarily in the Southern US) one may see an older LVTP/LVTC-7 in US hands. Italy’s San Marcos Marines are also known users of the AAVP-7A1. Perhaps 15% of the US Marines’ AAVP-7A1s are actually modified to the AAVP-7A1/25mm standard; these are called AAVP-7A2s.

Notes: Once the standard tracked amphibious carrier of the US Marines, the LVTP-5A1 is now used only by Chile, the Philippines, and Taiwan. It was designed shortly after World War 2 and was meant to provide invading Marines with protection during amphibious assaults. The vehicle is long and flat, and carries a large amount of troops and equipment. The troops access the vehicle through a large ramp in the rear, and the driver and commander have their own hatches. The commander has a cupola mounting a light machinegun in a hard mount. The troop compartment is actually large enough to carry a 105mm towed howitzer. 45 troops may be carried in an emergency, but all the troops must stand in this case.

Notes: When the Russian BMP-1 was first revealed to the West in 1967, it was a huge shock to NATO – they thought that the Soviets had a new class of armored personnel carrier that was easily better than anything they had, with armament that allowed the BMP-1 to defeat NATO’s APC and light armored vehicles and possibly even some tanks, as well as allowing their infantry to fight on an NBC battlefield. This was before some of the shortcomings of the BMP-1 were known; however, the essential point was clear – NATO’s "battlefield taxis" were no longer up to the task for most purposes. On top of that, it was clear that the M-113 series could not keep up with the speedy M-1 Abrams in the attack. Though most NATO countries were quick to follow up on the new concept of IFVs (Infantry Fighting Vehicles), the US took nearly 15 years of budget wrangling and infighting between the Infantry and Cavalry branches of the Army to field an IFV – the M-2 Bradley.

The original version of the Bradley, the M-2 (sometimes referred to as the "A0" version), was first issued to US Army troops in 1981 (though they were not considered operational until December of 1983). The most marked difference between the Bradley and previous US personnel carriers was its turret with its heavy armament. The Bradley uses a two-man turret, with the gunner operating a 25mm M-242 ChainGun (called the Bushmaster) and a twin TOW missile launcher contained in an armored box on the left side of the turret. The commander (called a "BC" by Bradley-mounted infantry, for "Bradley Commander") has no pintle-mounted armament on his hatch, as his weapon is considered to be the coaxial M-240C machinegun. The gunner also has controls for the coaxial machinegun, however, and the commander has auxiliary controls for the ChainGun (though not the TOW missiles). Both the gunner and commander have roof hatches with periscope-type vision blocks (the gunner has them to the left side, front, and about 30 degrees to the right side; the commander’s hatch is completely ringed with vision blocks), with no magnification. However, the gunner’s front periscopes are completely blocked by the head of his weapon sight in its armored box. The gunner has a 5x/12x image intensifier/thermal imager to use in conjunction with his gun/missile sight; the commander can also use this sight through an optical relay. The commander and gunner also have simple magnified reticle gunsights to take quick shots with the ChainGun or coaxial machinegun at close-range targets, and these simple sights can be used from an open hatch if necessary. Both also can share an auxiliary 5x telescopic sight. The commander’s and gunner’s hatches may be locked fully open (i.e. 90 degrees), or locked open to a little less than half that, letting them sort of peek outside with minimal exposure. The turret is capable of two rotation rates; 30 degrees per second is considered a standard rotation rate, but a high-speed 60 degree-per-second rate is also available. The turret can also be rotated manually, and the gun and coax elevated and depressed manually, in the case of electrical failure. Once a target is just about lined up, fine adjustments to the direction the turret is pointed can also be made if necessary.

The ChainGun and the coaxial machinegun can be elevated to +59 degrees (+57 on the M2A1 and later) and depressed to -9 degrees. They cannot be independently elevated or depressed. Both are stabilized for fire on the move, at a full clip. This was thought to be adequate when the Bradley was designed, though urban warfare in Iraq has shown that in the case of elevation, it’s not enough. Ideas were floated to try to increase the elevation, but the construction of the turret simply makes this impossible. (This has led to an experimental retrofit of an external M-249 SAW [see below], and BCs are sometimes seen with M-16s or SAWs in their hands, or even the excess M-231 port firing weapons that are have fallen into almost-complete disuse with the M-2A2 and later versions of the Bradley.) The M-242 is unusual for a vehicle-mounted autocannon in that it can be set for semiautomatic fire; two other fire rates are available for the M-242 – 100 rpm and 200 rpm. The M-242 is a dual-feed weapon, and the gunner may switch between belts with a simple flick of a switch (though for game purposes, and to simplify things, ammo from only one belt may be fired per semiautomatic shot or burst). The M-242 is electrically powered, but the M-240C coaxial is a variant of the standard M-240B infantry model, with spade grips and a sort of chute to vent the gasses of the fired rounds outside. The spent cases from the M-240C are caught in a bag attached to the machinegun; spent cases from the ChainGun are automatically dropped outside the turret through a slot forward of the "mantlet;" a rotating mechanism cycles during operation of the ChainGun and case "ejection" is part of this cycle. A pair of four-barreled, electrically-triggered smoke grenade launchers is found at the front of the turret, with one pair of launchers found on either side of the main gun and coaxial. Above these launchers are boxes which contain eight more grenades each. Originally, the Bradley could lay a thick, oily smoke screen by injecting diesel fuel into its exhaust, but with the change in the US military to a common fuel of JP-8 jet fuel, this capability has become superfluous, as injecting JP-8 into the exhaust won’t produce a smoke screen. Nonetheless, the Bradley still retains this capability (though today it is normally disabled).

The TOW launcher’s armored box is on the left side of the turret. It should be noted that while the box is armored, it is not as well-protected as the turret itself; it’s armor rating should be considered only 4 from the left side, and 2 from the front or rear. For firing, the box swings upwards to the side 90 degrees; about 10 seconds at a minimum are required by a good gunner to raise the launcher to firing position and take a shot. Though the TOW launcher box itself can be elevated to a significant degree and even depressed a little (+29 and -19 degrees), the TOW missiles cannot be controlled effectively in flight unless the launcher no more than +10 degrees and -0 degrees from being horizontal to the ground, due to the wire guidance of the TOW-series missiles for which the Bradley’s launcher is designed. (The M-2 Bradley TOW launcher is designed for TOW-1 series missiles.) Reloading of the launcher box is done by turning the turret to left a small amount (less then 5 degrees) and elevating the launcher box to its maximum elevation. Behind the turret on the rear deck is a narrow rectangular hatch that opens just enough for the crew or infantrymen in the rear to slide more missiles into the launcher box (i.e., one cannot stand up in that hatch and can just barely even peek out of it). If a TOW is in flight, the BC’s fire and turret rotation controls are locked in order to avoid a spoiled shot; the gunner also cannot rotate the turret if a TOW is in flight (though he can abort the TOW missile if necessary). After the TOW hits its target (or the gunner aborts), the guiding wires release from the launcher and fall off. It should be noted that the TOW launcher cannot be used on the move; the Bradley must be stationary in order to fire the TOW launcher.

The passenger compartment is for the most part in the rear of the Bradley, though two of the dismount infantrymen have seats on the left side of the turret. Though the entire passenger compartment is really cramped, those two seats are even more cramped. The rearmost passenger seat is in a particularly small space (one generally puts the smallest man back there), and that man is sitting with his back to the driver with only about a half a foot separating him from knocking heads with the driver. (When I was in mech infantry, this was often called the "die-in-place" seat…). In the M-2 Bradley, there are four more passenger seats; one on the left side facing forward, one on the left side facing to the rear, one on the left side facing to the rear, and one between those two facing to rear (generally used by the squad leader, who is also part of the dismount squad). The passengers in a "plain vanilla" M-2 have firing ports and periscopic vision blocks to allow them to observe outside the vehicle, with the exception of the center rear seat, which has only a vision block. While it is a bit awkward, the four troops on the sides of the M-2 version have to turn sideways in their seats (this is one reason the sliding wire stocks on the M-231 port firing weapons were quickly deleted). The passenger seats can also be folded up and stowed completely out of the way. In addition, effective fire is difficult from the firing ports unless the weapons are loaded with almost entirely tracer ammunition, as vision outside the vehicle is diminished, there are no night vision devices for the firing ports, weapon sights cannot be used, and there is a slight parallax error (the periscopes actually show a field of view about a foot above the weapon and are wide-angle lenses). The rear of the passenger compartment has an electrically-lowered ramp with a hydraulic backup, and an oval hatch is set inside the ramp on the right side. (This door has an interior lock as well as an exterior padlock; the padlock is primarily for use when the Bradley is parked in garrison to prevent unauthorized access.)

The driver is in the front right side of the vehicle, with the engine compartment to the left of him. Like all seats on the Bradley, the seats are (somewhat) padded to reduce crew fatigue, and the backrest can be folded down. The driver can enter his position from the passenger compartment, or through his overhead hatch. The driver’s hatch may be locked in a 90-degree open position or open about 30 degrees; when the Bradley is in combat, the hatch is normally closed or at the 30-degree position, as the 90-degree position blocks rotation of the turret. (The turret rotation system has an interlock which keeps the turret from rotating if the driver’s hatch is at the 90-degree position, in order to avoid bending the ChainGun’s barrel if it were to slam into the hatch while rotating.) As the driver’s hatch has as much armor as the rest of the top of the hull, it is too heavy to push open from a seated position (especially to a full 90-degree position). The hatch is therefore spring-loaded to a greater degree than the commander’s or gunner’s hatches.

The Bradley is protected by an aluminum alloy/steel laminate; for most of the vehicle, this armor also consists twin sections of armor spaced approximately 25mm apart to provide extra protection from HE-type projectiles. The floor of the Bradley has an additional centimeter of steel plate to increase mine protection. Track skirts with the same protection as the hull sides protect the sides; they hinge upwards for maintenance access. The M-2 version of the Bradley uses a Cummins VTA-903T diesel developing 500 horsepower; the suspension is exceptional for an APC, giving an unusually smooth ride. The M-2 version is also amphibious with preparation; about 15 minutes are required for an amphibious crossing, and requires the erection of a trim vane at the front and a flotation screen all around the vehicle.

Early experience with the M-2 revealed some shortcomings; this resulted in the M-2A1 being introduced in 1987 (though retrofitting of the central gas particulate NBC system for the driver, commander, and gunner began in May 1986). Improvements were made to the TOW missile system; these changes were primarily to allow use of the TOW-2 missile series as well as somewhat quicker target acquisition, and simplify construction and lower cost. (At first, replacement of the existing TOW launching box with a pair of non-moving launcher boxes, one on either side of the turret, was considered, but rejected as unnecessary). On the M-2 version, the turret bustle rack was angled inward; while this was ballistically more sound, it also seriously limited the storage space in the rack. The bustle rack on the M-2A1 was therefore given a square profile as well as enlarged. Ammunition storage in the bustle itself was also rearranged to allow more of the 25mm ammunition to be stored in the bustle instead of being distributed around the interior of the Bradley. Under-armor storage compartments were also added to the sides of the Bradley, though these were accessible only from the exterior of the Bradley and designed primarily for additional 25mm, 7.62mm, and 5.56mm ammunition storage. The storage for additional smoke grenades (for the grenade launchers) was removed from boxes just above the smoke grenade launchers on the turret to boxes at the rear of the vehicle on either side of the ramp; these boxes can hold a variety of mines, flares, grenades, or smoke grenades for the vehicle launchers. A thin layer of appliqué armor was added to the glacis and a small portion of the upper sides. In the interior of the M-2A1, the spall liner was improved, and a new fire suppression system was added inside the fuel tanks. The seating and stowage arrangement of the M-2A1 was rearranged, allowing for one more infantryman to be seated in the rear. The user of this seat does not have access to either a firing port or a vision block.

There had always been considerable controversy about the survivability of the Bradley. This controversy came to a head in 1984, when a series of live fire tests against M-2 versions of the Bradley were conducted. The tests were full of irregularities (for the most part in the proper combat loading of the Bradleys involved in the test), but eventually a live TOW shot against the side of a fully combat-loaded Bradley resulted in the vehicle being destroyed in a spectacular fireball. Development of the M-2A2 version of the Bradley (sometimes referred to as the Bradley II) dates to this point.

The changes from the M-2A1 to the M-2A2 were extensive, and centered around the fitting of heavier armor and lugs on the sides for reactive armor. In fact, the side armor was beefed up to the point that the sides of the Bradley were totally plated over. One immediate result of this extra armor was the loss of the side firing ports; their places on the hull were covered by the added side armor. (One vision block on either side was retained.) In addition, virtually the entire vehicle received increased armor protection – even the bustle rack was given an extra section at the rear – it can not only carry additional gear, but acts as a second layer of spaced armor. Internally, the interior of the M-2A2 was protected with an even thicker Kevlar spall liner of more modern design. The thickness of the armor on the front of the turret led to the deletion of the barrel jacket for the M-240C coaxial machinegun, and a slight redesign of the barrel extension for the M-242 ChainGun. Lugs for reactive armor blocks are found on the upper sides of the M-2A2 as well as on the glacis. These lugs can also mount bolt-on appliqué armor, bolt-on spaced armor, or the new slat armor if desired. The weight of the M-2A2 increased so much that it is no longer amphibious, and the trim vane and flotation screen have been removed. However, to cope with the increased weight, the VTA-903T was replaced with an upgraded version of the same engine, developing 600 horsepower.

Some smaller physical changes include retractable metal covers over the driver’s periscopes, along with a wire guard to protect the driver from wire and obstacles strewn across the Bradley’s path. Due to the changes in the frontal armor and the potential for the mounting of ERA, the design of the headlights was changed. Due to the loss of the side firing ports, the seating arrangement was again changed; on the sides of the passenger compartment, three troops sat on each side, and the "die-in-place" seat was retained. (Initially, this seat was to be removed and the dismount squad reduced back to six, but this decision was rethought.) The second seat on the left side of the turret was, however, deleted. Internal stowage, especially for the TOW missiles (and the infantry squad’s Dragons and M-136s) was again re-done (and again years later when the Javelin replaced the Dragon).

After operations in 1991’s Desert Storm campaign, several additions were made to the M-2A2 in response to crew wishes, new operational requirements and capabilities, and, unfortunately, the relatively high percentage of losses due to fratricide. This package of modifications was referred to as the ODS (Operation Desert Storm) upgrades, with such modified vehicles informally called M-2A2ODSs. Modifications included an improved, eye-safe laser rangefinder, the addition of a GPS system, an IFF system, thermal imaging for the driver, and a system to jam radio-guided and IR-guided missiles (regarded as only partially effective, but better than nothing). The missile jamming system consists of sensors to detect incoming missiles and automatically put out low-grade radio-jamming signals, launch flares and IR-defeating smoke grenades.

By 1995, operations during Desert Storm had been more fully evaluated. At the same time, the introduction of the M-1A2 Abrams III meant that the Abrams now had several important capabilities the Bradley lacked, and this led to the M-2A3 (sometime called the Bradley III). The largest change in the Bradley was internal; the Bradley was given computers and communications equipment to allow it to inter-operate with the Abrams III and the AH-64D Apache on the digital battlefield. The commander has a full flat-panel display/touchscreen and computer control; the gunner and driver have touchscreens of their own that display information appropriate to their roles. In the passenger compartment, mounted on a bracket that is against the turret basket but not actually attached to it (i.e., it does not rotate with the turret), is another large display to provide the dismount squad with information on the battlefield situation and allow them to plan, receive and provide updated information. Along with this capability, GPS and an INU (Inertial Navigation Unit) have been added. The M-2A3 has a computer (which has been steadily upgraded over time) to allow it to quickly receive, integrate, display, and send real-time battlefield information; commanders therefore (usually) know where their units are and their status; the Bradley is therefore a true counterpart to the Abrams on the digital battlefield. Rebuilding of existing Bradleys to the M-2A3 standard began in 1996, and by 2008 almost all Bradleys in the US Army inventory have been rebuilt to the M-2A3 standard.

Other improvements a CIS (Commander’s Independent Viewer), similar to the CITS of the M-1A2 Abrams III. The commander also retained the ability to see through the gunner’s sight. In addition, the thermal imagers were replaced with long-range FLIR systems more akin to those found on aircraft and helicopters. The M-2A3 has an automatic dual target tracking ability, and as the gunner’s sighted target is destroyed, the turret can be set to rotate automatically and the gun trained automatically on the commander’s sighted target. Fire control s also improved (the system called the IBAS – Improved Bradley Acquisition System), and boresighting is essentially automatic instead of requiring a stop and extensive adjustments. The gunner’s sight (the TAS – Target Acquisition System) has received particular attention in the fire control department. The main gun and coaxial machinegun is better stabilized and the ballistic computer improved (able to tap into, to a small amount, the primary computer of the Bradley). The TAS uses a 2^nd-generation FLIR and a day TV/image intensification device, with a digital zoom from 4x to 48x, and twice the field of view of the zoom sights of earlier Bradleys. The day TV/image intensifier sees in near-infrared as well visible light, making it usable even in heavy smoke, IR-obscuring smoke, and conditions of low thermal contrast where FLIR imaging would be of little use.

The turret roof of the M-2A3 has a thin layer of added titanium alloy armor, as Desert Storm operations revealed the turret roof to be the weakest surface of the vehicle. As an adjunct to the electronic IFF system, the Bradley accommodates special panels on the sides of the vehicle made of the special aluminum alloy. These panels, when viewed through thermal imagers or FLIRs of the proper wavelength, gives off a heat signature that provides a further deterrent to fratricide. The M-2A3 includes a special cooling system for the vehicle’s electronics, but experience in Iraq has led to low-power air conditioning to be fitted to the M-2A3 (and some M-2A2s still in service) to relieve the stifling heat that builds up inside the Bradley.

One of the newest members of the Bradley to be fielded is actually based on the FISTV version of the Bradley (the M-7, found in US Tracked Artillery Support Vehicles). This is the Bradley ACP (Assault Command Post), perhaps better known by its developmental name, the BCOTM Bradley (Battle Command On-the-Move). The ACP was first fielded in April of 2003, but at the time it was only an experiment – but a circumstance of the of combat during the Battle of Taji on 16 April 2003 dramatically demonstrated the ACP’s usefulness, as the pace of battle became to fast that 4^th ID’s DTAC could not arrive in time to set up and control the battle, and one ACP and a handful of other vehicles became the ad hoc DTAC for almost 18 hours.

The ACP is still considered a developmental vehicle, but more and more are in use in Iraq. They are currently found primarily at the Brigade HQ level and above, but plans are to eventually use ACPs down to Battalion level, and in a few other applications such as leaders’ reconnaissance. As a part of TAC-type units, the interior of an ACP is crammed full of computers, displays, radios and other gear necessary to rapidly display and control operations of a unit. In addition, the ACP has the same level of armor protection as a standard M-2A2, though the ACP has much less ammunition for its ChainGun, TOW launcher and coaxial machinegun. As there is only so much one can stuff into a Bradley, the ACP is usually accompanied in its duties by an M-1068 CPV version of the M-113. An ACP has approximately six times the computing power of an M-2A3, and information is displayed on three large displays that are linked via a KVM and can simultaneously accept input from the three operators, the on-scene commander, the M-1068 that accompanies the ACP, and higher headquarters via radio, using a special version of a standard Cisco-made router. The three large monitors can be swung to the sides to allow personnel to get in and out of the ACP. The ACP also has a Toughbook laptop with a secure wireless connection to the ACP. The ACP can be equipped with up to ten radios, though five or six are more common. An external receptacle allows the entire ACP to be connected to an external generator to power the huge amount of electronics without rapidly draining the ACP’s batteries. In addition, the electronics have two large UPSs to power them in emergencies or when generator switch-overs or maintenance are necessary. Needless to say, the ACP is definitely a cramped vehicle inside, but a commander can pretty much use an ACP to go wherever he needs to during a battle.

As a result of experience in Iraq, the Bradley’s designers have come up with the Bradley Urban Survival Kit (BUSK) for the Bradley, similar in concept to the TUSK for the Abrams tank. This kit consists of a number of large and small modifications that can be applied at the unit level, and largely grew out of informal modifications that were already being used by Bradley crews. One of these is a handheld 3-million-candlepower spotlight, which may be powered by a rechargeable internal battery or by the vehicle’s electrical system through a cable. In order to protect the crew and passengers from accidental electrocution if the antennas contact low-lying electrical wires (something I’ve actually seen happen in Korea), BAE Systems came up with antenna mounts that allow the antenna to be retracted with an electric motor (and a manual backup). In addition, a dome like-structure, consisting of a pair of flexible poles of a non-conductive material, can be mounted on the turret. (Bradley crews usually refer to this as a "tent," though it does not actually have any side panels.) These poles attach to the front, back, and sides of the top of the turret and meet at a 90-degree angle at the top, protecting against a lot of debris and wires that may hang across the road. Racks have been devised to give the crew and passengers extra external stowage for their gear on the sides and front of the Bradley; this not only cleans up the exterior stowage, but has the incidental effect of increasing the protection level of the Bradley (primarily by absorbing some small arms fire and pre-detonating shaped charge warheads.

One of the most interesting parts of the BUSK is CLAW. The CLAW (Commander’s Light Automatic Weapon) mount is still considered an experimental part of the BUSK (as of this writing in June 2008) and consists of a mount attached to the side of the CIV, so that the attached weapon (which may be an M-231 PFW, but is most commonly an M-249 SAW of any variety) is just above the CIV. The mount also allows for standard belt containers to be attached to the SAW. The weapon attached it a standard, unmodified version, so it may be easily unclipped from the CIV and used normally. The mount includes a mechanism to pull the trigger of the attached weapon, with a cable leading to the commander’s position that allows him to fire the weapon while buttoned up, and aim it using the CIV.

Twilight 2000 Notes: In Twilight 2000 pre-war active-duty US Army units, slightly over 60% of Bradleys are M-2A2s, with about a quarter of those M-2A2s being M-2A2ODSs. Most of the rest of the Bradleys in pre-war active-duty units are M-2A1s, but about 5% are "plain vanilla" M-2s and about 2% are M-2A3s. In pre-war Guard and Reserve units, Bradleys are almost half-and-half M-2s and M-2A1s, with about 10% being M-2A2s. The BUSK does not exist as such, though many of the BUSK features were added to Bradleys on an ad hoc basis. The M-7 ACP does not exist in the Twilight 2000 timeline.

*Floor armor for the M-2 and M-2A1 is 5; for the M-2A2, M-2A3, and M-7 ACP, it is 7. The turret roof of the M-2A3 has an AV 7.

Notes: By 2000, this famous veteran of World War 2 was long out of service in most countries, being actively used only by Yugoslavia, some South American countries, and in a reserve role in Israel and Lebanon. It was an attempt to provide an armored personnel carrier with the maneuverability and fuel efficiency of a medium truck and the cross-country capability of a tracked vehicle. The Half-Track was easy to make, but was a poor compromise between a truck and a tracked vehicle, not having the good attributes of either. In addition, it is open topped, providing no protections against air attack, airbursting munitions, or even a lucky grenade throw. They are easier to repair than a full-tracked vehicle, but not as mechanically simple as a full-wheeled vehicle. By 2000, most Half-tracks were being used as specialist vehicles such as weapon carriers, artillery tractors, ambulances, and logistics carriers, instead as APCs. There are doors on either side of the cab for the driver and commander, and a door on the rear of the hull for passengers. Over the commander’s position there is a ring mount for a heavy machinegun, and on each side of the passenger compartment there is a mount for a medium or light machinegun.

Notes: The M-4 C2V is a derivation of the M-2 Bradley chassis, designed to replace the M-577 in the command and control role. The M-4 uses a large, box-like enclosure fitted onto the back of the vehicle; the turret has been deleted, and the whole thing looks similar to the M-993 MLRS (which is also derived from the Bradley chassis). The M-4 has a 10-meter telescoping mast for its antenna system, which is able to simultaneously service 7 radios (included in the basic cost of the vehicle). The vehicle also has computers, map boards, a fax machine, and NBC protection.

Notes: This US armored personnel carrier was the predecessor to the M-113 series. It was an improvement over the M-75 APC used before it, but it is still a poor vehicle. The US Army replaced it with the M-113 in the early 1960s, but the M-59 is still used by Brazil, Greece, and Turkey. The M-59 uses two gasoline engines that are plagued by poor range, and the vehicle is amphibious only under ideal conditions. The only variant to enter production is a mortar carrier mounting an M-30 4.2" mortar.

Notes: This was one of the first US post-war APC designs, and also one if it’s first full-tracked APCs. It is a simple APC with a rectangular hull, topped with a ring-mounted machinegun. The driver is at the front on the left, with the commander to the rear of his position in the center. There are two large hatches on the rear roof for standing infantrymen, and two large doors in the rear of the hull. The gasoline engine severely limits the range, and the M-75 has no amphibious capability.

The last known user of the M-75 was Belgium, though these have since been replaced by the AIFV and M-113A2.

Notes: By the 1950s, the US Army already knew that their earlier APCs had essentially been failures; they were too big, too heavy, and too slow. The Army wanted APCs that could keep up with their main battle tanks of the time (the M-48 series and the then-projected M-60 series), and one that was amphibious, air-transportable, and if possible, air-droppable. Early prototypes of what would become the M-113, called the T-113, were ready for testing in late 1956, but revised requirements and new developments in aluminum alloy armor meant that the updated T-113E1 and T-113E2 prototypes did not begin their testing until October of 1958. Full production of the M-113, based on the T-113E2 prototype, began in January of 1960. The M-113 has since been upgraded and modified into scores of different forms; the M-113 series is regarded worldwide as one of the most adaptable platforms in existence. US crews typically refer to the M-113 series and most of its variants simply as "tracks."

The M-113 is basically a large armored box. There is a large overhead hatch designed for six of the passengers to stand with head, shoulders, and chest outside of it with their weapons (though I have seen as many as nine stuffed into that hatchway in actual use), and a hydraulic ramp at the rear with another hatch set into it on the left side. The ramp can be quickly opened by simply dropping it, or lowered more slowly by using engine power to help control the speed at which the ramp lowers. The handle to operate the ramp it to the rear of the driver, and it is the driver that is responsible for opening and closing the ramp under most circumstances. (The ramp is almost always opened in a controlled manner with the engine on, as without the engine on, the ramp will simply drop open once it is unlatched, which can damage the ramp’s mechanism. Without engine power, the ramp can be raised only with muscle power, taking 3-5 troops, and this can induce too much slack in the ramp cable.) The rear of the vehicle has no firing ports or vision blocks (though some very early examples of the M-113 had a vision block on the left and right sides of the passenger compartment), and is simply an open space with bench seats that can be folded and locked, a few storage compartments for ammunition and munitions like grenades, a shelf for a radio or two, and damn little other room for anything else other than the passengers. Perhaps distressingly, the fuel tanks of the M-113, M-113A1, and M-113A2 are inside the left wall of the passenger compartment, behind rather thin plates of metal. The M-113 also has a heater for the interior, fired by the vehicle’s fuel supply. At the center front of the M-113 is a small cupola for the commander; this is rotated by the commander simply unlocking the cupola and pulling him around in whichever direction desired. The cupola has periscopic vision blocks for all-around vision when buttoned up, and a platform with a seat that can be raised and lowered as necessary. The commander’s cupola also has a pintle mount for an NHT, NMT, or NLT-compatible weapon (most often the M-2HB); in addition, an adapter was made to mount a Dragon ATGM on the weapon mount, and there is also an adapter to mount a laser designator (these adapters are extremely rare). The driver’s position is in the left front of the hull; his hatch is above him, to the front and left of the commander’s cupola. The driver has vision blocks that cover everything except the rear and part of the right-side arcs, and the front one can be easily removed and replaced with a passive IR periscope. The seat for the driver can be raised and lowered so that the driver may drive with his head outside the hatch or buttoned up. The controls consist of a gearshift, a gas pedal, and a pair of tillers to steer and brake the vehicle using differential steering. (Driving an M-113 with the tiller system actually requires a surprising amount of upper body strength – if you don’t have it, you’ll develop it pretty fast.)

The engine of the original M-113 is a Chrysler 75M gasoline engine, coupled to an automatic transmission with four forward speeds and one reverse. A sore spot about the M-113’s power pack is the position of the exhaust – it is on the right front corner of the deck, and those standing in the troop hatch often get a bit queasy, if not outright sick to their stomachs, from the carbon monoxide in the exhaust. Many countries have taken the step of extending the exhaust pipe and running it downward to a position just above the tracks. The M-113 is amphibious with a minimum of preparation (the trim vane must be lowered to its swimming configuration, which takes no more than 15 seconds) – but the M-113 must already have rubber track skirts installed. These bolt onto the sides of the M-113 over the top part of the tracks; when the M-113 enters the water, an air bubble forms over the top of the tracks to give the M-113 the extra buoyancy needed for it to float. Propulsion is by the movement of its tracks. (These rubber skirts are easily torn up in normal field operations, and they are usually left in the motor pool.) The M-113 has a bilge pump that pumps water out of the engine compartment and from under the floor of the M-113. The M-113 used a flat torsion bar suspension, another thing that could lead to troops feeing beat-up and queasy by the time they reached the AO; I’m not the only one who has thrown up during a long off-road M-113 ride!

As stated above, the original M-113 used a gasoline engine, developing 215 horsepower. In the conceptual and prototype phases, there were to be two versions: a lighter version for use by airborne, cavalry, and scout troops, and a heavier one to be used as a general-purpose carrier in mechanized infantry units. After evaluation of both prototypes (the T-113E1 and E2 mentioned above), it was determined that the T-113E2 could meet both requirements, if FMC (the manufacturer of the M-113 at the time) could drop about 180 kilograms of weight. This was done by reducing the thickness of the rear armor and on the sponsons somewhat, but most of that weight was taken out of the floor of the vehicle. This short-sighted idea would have deadly repercussions in the future; the M-113 series is quite vulnerable to crew casualties from mine damage.

Evaluations of the vehicle which would become the M-113A1 began in June of 1959, even before the original M-113 began production. The primary thrust of the modifications was the replacement of the gasoline engine of the M-113 with a diesel engine, and also making the engine, differential, final drives and transmission into an integrated power pack that could be removed as a unit for servicing, or serviced as individual components. The exterior would remain largely the same as that of the M-113. The M-113A1 entered service in 1964.

The engine chosen for the M-113A1 was the General Motors 6V53, which developed 212 horsepower and offered much better fuel economy; the better transmission of the M-113A1 ensured that the speed remained the same despite the lower horsepower rating of the engine and the greater weight. This engine and the integrated power pack concept required a new transmission. Originally, the M-113A1 was to have the differential steering system and its tillers replaced by a more conventional steering yoke and brake, but the transmission that was first chosen for the M-113A1 proved to be unreliable, and modifications to this transmission also did not work out. Objections to the original transmission were also raised by the soldiers involved in testing, since it was a manual transmission. The transmission was therefore replaced with an updated version of the M-113’s original transmission, which unfortunately required that differential steering be used. The fuel capacity of the M-113A1 was also increased over the M-113; it was felt that larger fuel tanks could be put into the walls, since the fire hazard of diesel fuel was much lower than that of gasoline. Minor changes were made to improve the safety of the crew compartment heater. On the M-113, the same mechanism that provided crew heat also included ducts to heat the engine and the batteries in cold weather; on the M-113A1, a separate, temperature-sensitive mechanism heated the coolant before it circulated through the engine and also supplied heat to an exchanger in the battery box as appropriate.

The M-113A1 was considered extremely reliable mechanically and adequate as an APC. However, Vietnam revealed some deficiencies (other than the mine vulnerability). This resulted in the M-113A2, introduced in 1979.

The location of the radiator and fan on the M-113A1 tended to make the engine a bit hot, as dust and oil would build up on the radiator core. The positions of the fan and radiator were reversed to improve air flow, and the radiator itself replaced with a larger one with more coolant capacity.

The torsion bars of the suspension were replaced with stronger, yet more flexible ones; the increased travel capability of the roadwheels increased off-road performance. The idler wheel was replaced with a stronger one that was also raised about 50 millimeters to contribute to the increased off-road travel. The first, second, and rear roadwheels used improved shock absorbers that also helped increase off-road performance as well as smooth out the ride (a little…). The entire ground clearance of the M-113A2 was raised by 25 millimeters.

Perhaps the greatest change in the M-113A2 was in the power pack. The 6V53 engine was replaced by the turbocharged 6V53T, which develops 212 horsepower and has an improved cooling system. The transmission was also improved, with an additional forward speed. The M-113A2 also added neutral (pivot) steering capability, with the pivot steering handles being located at the front of the driver’s compartment above and in front of the tillers; however, most M-113A2s have them disconnected as it was found that the M-113A2 easily throws tracks under pivot steering, even when simply turning in place.

The M-113A2 also introduced a smoke grenade launcher kit; this consists of a pair of four-tube launchers mounted on either side of the front of the hull, above the fenders. Originally designed specifically for white or dark smoke vehicular grenades, these launchers were later modified to permit the use of colored smoke or IR screening smoke as well. The grenades are electrically fired, with a control box on the top of the wall of the engine compartment in front of the commander’s position.

The increased weight of the M-113A2 made swimming perilous; the tech manuals say that an M-113A2 has a freeboard of 14 inches when fully loaded, but in practice, the freeboard is typically 10 inches or less, and it is quite possible for M-113A2s to sink in even moderately choppy water. For this reason, normal practice is to leave all top hatches of a swimming M-113A2 open so that the occupants can quickly escape if the M-113A2 sinks. Several types of buoyancy cells were tried, ranging from the ones mentioned in the Mine Reduction Vulnerability Kit below to inflatable ones, but in the late 1980s, the amphibious requirement for the entire M-113 series was dropped, and the M-113A2 was to swim only in emergencies. Many units have not been even mounting the trim vanes on their M-113-series vehicles since the late 1980s.

Development of the M-113A2 continued. The transmission of the M-113A2 was eventually upgraded three times; in a way, the use of these improved transmissions was sort of a test program, for they would allow the use of a new version of the 6V53T engine called the RISE package that had improvements to power and the drive train. In addition, many M-113A2s had Kevlar anti-spall panels added to the interior. The M-113A3 would include the new transmission, the RISE package, and many other improvements. The M-113A3 was introduced in 1987.

The M-113A3’s engine develops 275 horsepower; in addition, the M-113A3 has what drivers have been wanting for a long time: a conventional steering yoke and a brake pedal instead of the differential steering and braking system. This greatly reduced driver fatigue. The passive IR periscopic sight was replaced with a thermal imager. An improved neutral steering system was fitted, restoring the pivot steer capability. Kevlar anti-spalling liners were fitted to increase protection for the occupants. Finally, the external fuel cells were made standard equipment on the M-113A3, also greatly increasing crew survivability.

The M-113A3 is not "officially" amphibious; buoyancy cells of the type listed below can be added to the M-113A3’s sides and to the trim vane, but swimming an M-113A3 is even more dangerous than swimming an M-113A2. Many appliqué armor kits have also been devised for the M-113A3 (see below), and any of these make the M-113A3 too heavy to swim.

Though the M-113 appeared in 1960, command, FDC, medical, and other specialist elements in mechanized or armored formations were still using M-59 APCs that used a plethora of ad hoc modifications. These ad hoc command vehicles had the same vulnerabilities and poor range of the M-59, and the electrical systems of the M-59 were often not up to the job they were given, particularly if the command vehicle carried a lot of communications equipment. The development of a CPC version of the M-113, designated the M-577, was given a high priority, and first issue began to US Army units in Europe in December of 1962.

The M-577’s most obvious difference from the M-113 is the raised roofline; behind the driver’s position, the roof has been raised by over 64 centimeters, allowing those inside to stand upright. The single fuel tank in the left side of passenger compartment was replaced by two fuel tanks, one in each side of the passenger compartment. These fuel tanks were mounted so that they extended down the sides of the compartment, and covered so that they formed a work shelf. Attached to these work shelves are folding wooden extensions (in two sections on each side; most M-577s I’ve seen have the front-most shelves removed, and some even have the left-side shelves removed entirely). The vehicle commander’s position was also radically changed; the M-577 has no commander’s cupola. Instead, the M-577 has a hatch in the roof that is about 25% larger than an M-113 commander’s hatch, making it large enough for large pieces of equipment (such as observation devices and designators) to be moved into and out of the vehicle from the top hatch. The commander’s seat has been removed; replaced with a simple folding metal stand. Contrary to the Twilight 2000 rule books, the M-577 does not have a mount for any weapon by the commander’s hatch or anywhere else on the vehicle. The commander’s hatch also has no vision blocks. The M-577 does have a bracket beside the driver for his M-16 or M-4, another bracket above the rear ramp (on the inside) that will hold an M-16/M-4, an M-60 machinegun, an M-240 machinegun, or an M-249 SAW. Below this is another bracket that will hold an M-16/M-4 or an M-249. (I discovered in Korea that either one will also hold an AKM or the South Korean K-1A1 or K-2 rifles.)

The passenger compartment has folding bench seats on either side of the passenger compartment (another feature normally removed by units; they get in the way). At the front of the raised roofline, to the right of the driver’s position and in the center of the front deck, is a metal box permanently attached to the M-577; this is designed for a 4.2kW gasoline-powered generator to power the electrical equipment without having to run the engine for long periods of time. To the rear of the driver’s position are brackets for a lifting davit to allow the generator to be put on the ground and dug in to cut down on the incredible noise the generator puts out. A 50-foot generator cable is provided to allow this, and a shorter one is also provided if the generator is to be run from its carrying position on the M-577.

Other items which may be found (depending on configuration and purpose) on the M-577 include a 3x3 cabinet with several drawers and a fold-out table; 3-5 folding metal chairs; a 1.2x1.8-meter map board that attaches to the right inner wall of the vehicle; and a variety of shelves (and ways to mount them) for the equipment the M-577 carries. An M-577 generally carries several radios; the one I worked out of in Korea had four SINGCARS radios, a medium-range AM radio, and a long-range AM radio. Inside the M-577 are both white lights and blackout lights to light up the interior. Though they may not all be used at the same time, there are mounts for up to five antenna aerials; in addition, a very-long-range antenna may be mounted on in the davit brackets. At the rear of the vehicle, on either side of ramp on the outside, are connections for four field telephones, two generators, and two pairs of conventional electrical outlets to allow other equipment to feed off of the M-577 (generally done only if the M-577 is itself feeding from a generator). An M-15 collective protection system, to which the troops inside the may hook their protective masks, can be mounted in the M-577, but is not standard equipment; this system is powered by the 4.2kW generator. An airlock system can also be attached to the rear of the M-577, but it is quite rare; it is also powered from the generator. Something that is standard equipment is a work area-extension tent and poles; these attach to the rear of the M-577, and add approximately 4x5 meters of enclosed workspace. When not in use, these stow in special brackets and lash-down points atop the ramp entrance. (Of course, the tent does make emergency moves a bit difficult…)

Other modifications paralleled to some extent those for the M-113. The M-577A1 brought the same power pack changes as the M-113A1, though fuel capacity remained the same as the M-577. The M-577A1 began issue in 1964. The M-577A2 likewise followed the same power pack and suspension improvements as the M-113A2, as well as adding the smoke grenade launchers. Issue of the M-577A2 began in 1979, with both new M-577A2s being built and earlier M-577s and M-577A1s being upgraded to the M-577A2 standard. The M-577A3 also included most of the improvements of the M-113A3; in addition, the 4.2kW gasoline-fueled generator was (gradually) replaced by a 5kW generator that could be powered by diesel of JP-8 jet fuel. M-577A3 issue began in 1994.

The M-1068 SICPS (Standard Integrated Command Post System) began as a modernized M-577A2, but with the advent of the M-577A3, the M-577A3 was made the base vehicle for modifications, and the resulting vehicle re-designated the M-1068A3. The interior of the M-1068A3 held two folding semi-bucket seats for the crewmembers, and the standard TC’s stand and the driver’s position. The M-1068A3 has a dramatically beefed-up electrical system to allow the use of the ATCSS (Army Tactical Command and Control System), with its multiple communications systems, computers, touchscreens, and ancillary equipment; the M-1068A3 also carries various other equipment in drawers and shelves similar to the other members of the M-577A3 series. The extension tent was re-designed (primarily to save weight) and also contains a lighting system for the tent.

Notes: In Vietnam, an attempt to increase the firepower and protection levels of M-113s, particularly those operated by scout units and those operated by the ARVN. This led to various ad hoc modifications (parts of which later became kits made by FMC), which were informally called ACAVs (Armored Cavalry Assault Vehicles). Though the ACAV appellation later became more-or-less standard, ACAV versions of the M-113 have never been official versions of the M-113, and do not have any special designation other than "ACAV" hung after the type of M-113 in question. ACAVs were typically used as scouts, convoy escorts, or to spearhead assaults.

The first ACAVs were vehicles of the 11^th ACR, based on the M-113A1. The first of these modified vehicles entered combat in 1966. The increase in firepower and protection for the gunners was considered astounding, but more importantly, it increased the confidence of the crew. These first ACAVs had an armored shield for the commander’s cupola and the M-2HB (with a cutout for hatch in the rear), and M-60 machineguns on each front corner of the rear deck hatch on pintle mounts. A lug for a pintle was also mounted on the inside of the rear deck hatch. These gun shields have an AV of 2. Crews often armed one of their members with an M-79 grenade launcher and a large ammunition supply inside the ACAV. Some ACAV crews mounted other weapons on their ACAVs that were compatible (or jury-riggable), such as Miniguns, extra M-2HBs, or the XM-175 or Mk 19 automatic grenade launchers. With the gun shield removed, the rear weapons mounts could also mount 75mm, 90mm, or 106mm recoilless rifles. Experiments were also done with reduced-sized Claymore mines (often called "Minimores") attached to the sides of the ACAVs (full-sized Claymores would damage the M-113’s hull). ACAVs were sometimes additionally protected by kits such as the Mine Vulnerability Reduction Kit (below) or bolt-on steel or aluminum plates; sometimes the crews took a cute from World War 2 vehicles and built frames for sandbags to protect vulnerable areas (sandbags on the floor of the ACAV were quite common). Telescopic, periscopic, or night-vision devices were sometimes added to the weapon mounts. The ACAVs would also be loaded with as much ammunition as possible, and typically carried only as many crew members as necessary to man their weapons.

After Vietnam, the ACAVs were converted back to their standard M-113 configuration, and largely seen only in museums. However, in Iraq, some M-113s have become ACAVs in all but name, and kits are available to convert the M-113s to "ACAVs," sometimes further bolstered by the P-900 armor kit (see below) or other appliqué armor.

In the late 1960s, a waterjet propulsion system was developed for amphibious operations. This allowed the M-113A1 on which it was tested to roughly double its swimming speed and greatly increase waterborne mobility. The waterjets were steered by vanes. Air was sucked in from the top of the waterjet modules and pushed out under the water level to form the jets. Ballast was added in the front to ensure stability. The waterjet system was, however, decided against by the Army. In game terms, adding a waterjet propulsion system adds 300 kg to the weight of the vehicle (which is subtracted from the M-113s cargo capacity) and adds $4000 to the cost of the vehicle.

One of the interesting and creative uses for older M-113s (mostly M-113A3s and M-113A2s modified with the M-113A3’s power train) is being done at the US National Training Center (NTC) at Fort Irwin, California. Designated the M-113 OSV (OPFOR Surrogate Vehicle), this vehicle is a VISMOD (Visually-Modified) that is altered in appearance, and to some extent mechanically and operationally, to resemble the BMP-2. Most of this is done with fiberglass, sheet metal, and Kevlar add-ons to change the appearance of the M-113. Atop the M-113 OSV is a turret partially made with components of a Bradley turret, but designed to look like that of a BMP-2. The turret is largely non-functional, but can rotate and has useable vision blocks, hatches, and night vision equipment. The VISMOD is imperfect – the M-113 is too short and tall to really make it look like a BMP-2 – but it does have the advantage of actually being able to carry an infantry squad, something that the previous BMP VISMODs based on M-551 Sheridans cannot. In addition, the M-113 OSV uses about half the fuel of a Sheridan.

Non-APC-type M-113-based vehicles will generally be found in the other appropriate sections of the site (generally Light Combat Vehicles or Engineer Vehicles), according to which country developed them. A large number of experiments with the M-113 chassis were also postulated and tested (particularly in the 1980s) these will (eventually) be found in the various "Best Vehicles that Never Were" sections of this site.

With the advent of the M-113A1. FMC also devised a folding windshield kit for the driver for use in cold weather or when swimming. (Quite frankly, I’ve never actually laid eyes on one of these, though I’ve seen it in tech manuals and pictures…)

Experience in Vietnam resulted in various modifications and special kits for the M-113A1. M-113A1s used in Vietnam often got bogged down in mud, swamps, and rice paddies; this resulted in a special kit called a Marine Recovery Kit. The kit consisted of a pair of capstans which were bolted onto the drive sprockets, and a pair of high-strength nylon ropes with hooks on one end and large ground anchors on the other. The capstans, once attached to the drive sprockets and the recovery ropes attached, could allow the M-113A1 to pull itself out of bogged-down conditions as the ropes wound around the final drives. Once the M-113A1 was extricated, it would be driven in reverse to unwind the ropes, and the kit was removed. The capstan was stowed beside the commander’s hatch and the ropes and ground anchors were stowed on the left side of the vehicle.

The external armored fuel tanks were also available by themselves at an add-on kit for the M-113A1 and M-113A2. (For the M-113A3 and A4, they are standard equipment.) The tanks have a 95-liter fuel capacity (same as the internal tanks), and add 408 kilograms to the weight of the vehicle. The M-113A1 and M-113A2 cannot use both the internal and external tanks at the same time (unless either the internal or external tanks are simply used as giant fuel cans).

As stated above, the M-113 series is very vulnerable to mines and IEDs, due to the relatively thin belly armor. This problem hit home in Vietnam, where M-113A1s were knocked out by mines on a regular basis, killing, maiming, and injuring thousands of US and ARVN troops. In an attempt to reduce this problem, FMC devised the Mine Vulnerability Reduction Kit. This kit included plates of extra belly armor (adds 1 point of belly armor to most of the vehicle, but from the commander’s position forward, the armor increase is 2). A set of armored fuel tanks were devised to attach to the rear of the vehicle on either side of the ramp, along with a revised fuel line system that did not go through the floor. The driver’s seat was improved to take up more shock, including a shoulder harness. In the rear of the vehicle, the ramp had an emergency release to help the passengers to escape if the ramp control behind the driver was not quickly accessible. As this kit (especially the added armor) weighs about 1 ton and unbalances the M-113, buoyancy cells were added to the trim vane and sides to allow the M-113 to be able to swim; without these cells, swimming is dicey at best. (These buoyancy cells would also make an appearance later on certain special versions of the M-113 series).

Appliqué armor of various types have been proposed, tested, or used by various countries around the world. Most of these armor upgrades are simple bolt-on plates of additional composed of various materials (mostly metals), including aluminum and aluminum alloy, steel, and titanium. Ceramics, carbon fiber composites, and even a variant of Chobham have reportedly been tested. (The US Marines in particular have been experimenting with M-113A3s with ceramic appliqué armor.) Some of this appliqué armor is reportedly capable of defeating up to 30mm rounds without causing an undue weight increase or performance hit. Bar armor for the M-113 similar to that of the Stryker series is also being tested by the US in Iraq. Due to a lack of information, I will not go into further detail in this entry; I have included this paragraph for informational purposes only.

For the M-113A3, FMC devised a comprehensive appliqué armor kit called the P-900 kit. This kit consists of large sheets of extra aluminum plate (or steel plate for the belly) that bolt onto the vehicle. The P-900 kit pretty much adds protection to the entire vehicle, including spaced armor for the hull sides, added armor for the fuel tanks, and an armored shield kit that helps protect the entire commander’s cupola except for the rear. (This shield kit is almost identical to that of the ACAV kit’s cupola armor.) This extra armor adds a lot of weight and does affect performance, though the added horsepower of the M-113A3’s engine helps in this regard. This is the reason for the extra line below for an M-113A3 equipped with the P-900 kit.) I have not heard of any M-113A2s being augmented with the P-900 kit; I don’t see why it couldn’t be done, (though weight would definitely be an issue), since the Israelis have a similar kit for the M-113A2.

The Israelis have long been adding ERA to their M-113s; other countries that field the M-113 are also using them or testing the attachment of ERA to them. On the M-113, ERA is typically added only to the sides of the vehicle; it has been seen on the front on some Israeli and US vehicles, but due to the design of the M-113, there is a great danger of injuring the driver or even the commander due to an ERA tile detonation. In response to that danger, armored plexiglas windshields have been devised for the driver and commander. The rules for adding lugs and ERA to vehicles are well-covered in the Twilight 2000 v2.2 rulebook.

It should be noted that most appliqué armor kits will not kit on the M-577 series. However, with the M-577A3 and M-1068A3, bolt-on appliqué aluminum plates were devised that will fit the M-577A3 and M-1068A3, and lugs for ERA can also be applied.

Twilight 2000 Notes: Virtually all M-113-series vehicles in service worldwide in the Twilight 2000 timeline will be M-113A2s, though in third-world countries and even some allied countries M-113A1s and even M-113s will be quite common. There will also be a decent number of what are essentially M-113A1E1s (developmental M-113A1s with the power pack, drive train and most of the suspension improvements of the M-113A2) in service due to upgrade kits; these can be treated as M-113A2 for game purposes. In the US inventory, M-113A3s and M-577A3s will constitute about 20% of the fleet, while about 3% of the M-113-based CPCs will be M-1068A3s.

ACAV-type vehicles will comprise about 15% of the M-113-type APCs at the beginning of the Twilight War; these will be concentrated in brigade and battalion-level scout platoons. As the war goes on, more ACAV-type vehicles will appear, using either kits or ad hoc modifications. The P-900 kit is a rare but available modification; the MVRK kit is almost unknown.

As with Sheridan-based VISMODs, the M-113-based VISMODs have sometimes been used for infiltration-type raids and reconnaissance against Mexican and Soviet positions in the American Southwest – almost always with operational weapons installed.

*The MVRK gives the M-113 equipped with a belly armor AV of 4 from the commander’s cupola forward. Behind that, the belly armor AV is 3.

**Belly and top deck armor AV for P-900 kit-equipped vehicles is 4.

***For ACAV ammo, the figures for all weapons except for the commander’s M-2HB and the Minimores is shown as if all three additional weapons are of the same type. The GM must "mix-and-match" the amount of ammunition in the basic load as necessary if different types of weapons are used.

Notes: This is a stretched version of the M-113A3. The MTVL (Mobile Tactical Vehicle Light) can be distinguished by its extra set of roadwheels (six pairs instead of five) and the additional armor on the hull. It has a more powerful engine to cope with the increased weight. They were built as a test concept, but United Defense LP is now aggressively marketing them to countries already using the M-113 series and unable or unwilling to switch to big and expensive IFVs. Variants include the MTVL-CP, the equivalent of the M-577 in this series; the fuel tanks have been moved to the rear to provide extra interior room and reduce crew vulnerability. The M-577A3 has one extra pair of roadwheels (six instead of five), and is nearly one meter longer. The M-577A3 has the 4.2kW external generator of the normal M-577 replaced with a tactically quiet 5kW generator that can be operated from within the vehicle and uses the vehicle's fuel supply. The vehicle is also equipped with a 10-meter telescoping antenna mast. Another APC variant is the MTVL-LC; this is a dedicated logistics version of the standard MTVL armored personnel carrier. In this version, the rear cargo area normally used for troops is open-topped, drop-rear, and drop-sided, and the vehicle mounts a cargo-handling crane with a capacity of 6 tons and a reach of 5 meters. The MTVL-LC is normally used to haul ammunition for towed artillery or for armored formations.

Twilight 2000 Notes: These vehicles were primarily used by US National Guard and reserve formations.

Merc 2000 Notes: These vehicles were popular as they offered more power and protection than an M-113, but were less expensive.