Australian M113A1 Mods

     Notes: The Australian Army began using the M113A1 in the mid-1960s; they first used them in Vietnam as part of the small Allied force that was helping the US effort in the Vietnam War. Early Australian M113A1s were stock, but were quickly outfitted in a manner similar to ACAVs (an M2HB surrounded by a light armor shield, and a pair of M60 machineguns on either side of the passenger compartment deck hatch equipped with gun shields to the front).  However, soon after the Australian Army began operating in Vietnam, they began modifying their M113A1s to better suit conditions, improve firepower, and improve crew and passenger protection.  For budgetary reasons, the Australians stayed with the M113A1 version as a base design; many Australian troops also felt that the M113A1 was good enough for their purposes and that buying the M113A2 version was unnecessary.  However, later Australian upgrades have made the base M113A1s into vehicles that are in most cases better than the M113A2 and with later upgrades, better than the M113A3.

     Australian soldiers were at first ambivalent about the M113A1.  But their philosophy is best summed up in the words of one trooper, who said, “A second-class ride is better than a first-class walk.”

Standard M113A1s

     The stock version of the M113A1 and the M113A1 ACAV’s statistics and some of the information about them is repeated below from the US Tracked APCs page.  Some of these vehicles also received a “belly armor” upgrade, similar to the added hull floor armor used on some US M113s.  The engine chosen for the M113A1 was a slightly modified form of the General Motors 6V53 diesel, which developed 215 horsepower (slightly more powerful than US M113A1s, which had 212 horsepower); the transmission of the M113A1 is also matched to the engine. The different engine and transmission gives the Australian M113A1 much better speed than the US version. The M113A1 has an integrated transmission and power pack.  The driver operates the vehicle with tillers and a gas pedal; braking is done by pulling back on both tillers at the same time, while steering is done by pulling on one or the other tiller to brake either the left or right sprocket and final drive.  The driver also has a couple of handles above and in front of the tillers; these are pivot steer handles, and allow the M113A1 to turn in place. The transmission is automatic.  The fuel tanks are in the walls of the passenger compartment, inside the armor envelope.  Australian M113A1s has a crew compartment heater as well as a battery pre-heater.  The forward vision block can be removed and replaced with an IR vision block; this device is normally strapped on the wall on the left side of the driver, and can only be used if the driver lowers his seat to be completely under armor.

     The Australians quickly added an ACAV-type configuration; unlike early US M113 ACAVs, the Australians largely used a purpose-built kit manufactured in Australia.  The commander’s M2HB machinegun is surrounded by gun shields, which are slightly heavier than those put on US M113 ACAVs (but unfortunately cannot be reflected by Twilight 2000 v2.2 rules; it would translate out to an AV of about 2.3).  The gun shields for the M60s mounted on either side of the passenger compartment hull deck hatch protect against hits from the front of the gun only and have an AV of 2.

     Some Australian M113A1s were equipped with extra hull floor armor, which adds 2 points of armor to the floor of the M113A1. These were usually not added to other Australian M113A1 versions, to hold down weight.  The Australians also followed the lead of some US units by lining the floor of the passenger compartment with sandbags.

 The M113A1 APC/LRV

     The APC/LRC (LRV for Light Reconnaissance Vehicle) first appeared in the late 1960s.  The APC/LRV is a standard M113A1, but modified with the addition of a one-man Cadillac Gage T50 turret, similar to that mounted on the V-150 Commando Armored Car.  This small turret has a hatch on top and is armed with one heavy and one medium machinegun.  The primary motivation behind the APC/LRV was to afford the commander better protection; the increase in firepower from the commander’s position was an incidental benefit.  The turret does take up a bit of room normally given over to passenger seats, reducing the amount of infantrymen or equipment that can be carried in the rear.  The T50 turret does not provide any night vision or enhanced vision capabilities for the commander, but it does have several vision ports and blocks.  As with earlier versions of the M113A1, additional belly armor was sometimes fitted to the APC/LRV.  The Viet Cong referred to this variant of the M113A1 as the “Green Dragon” in the Vietnam War, as they were sometimes beefed up with additional weapons around the rear passenger hatch, making the APC/LRV into sort of an “ACAV Plus.”

 The M113A1 FSV

     The FSV (Fire Support Vehicle) was at the outset designed to be an interim vehicle designed to provide heavy backup to Australian infantry, with a secondary role as a scout vehicle. It was replaced in the late 1970s by the M113A1 MRV (below). The Australians had begun withdrawing their British-designed Saladin scout cars from active service in the mid-1960s, and some of the turrets of the Saladins were mounted on M113A1s.  This gave the M113A1 a 76mm medium-velocity gun with its coaxial machinegun and another machinegun mounted on a pintle at the commander’s hatch.  Though the turret and ammunition for the main gun takes up most of the room in the former passenger space, there is room for a small dismount squad.  The FSV retained its amphibious capability, but only because of Styrofoam blocks and air space enclosed by light aluminum sheet that were attached to each side of the hull and the trim vane. Australian troops referred to the FSV as “The Beast.” Some 15 FSVs are still in working order (if not in service) in Australia.  Added belly armor was generally not employed, as the weight would have been very detrimental to performance.

The M113A1 Recoilless Rifle Carrier

     The Recoilless Rifle Carrier variant of the M113A1 was another interim vehicle, designed to supplement the FSV as a fire support vehicle.  It was a simple modification; am M-40A2 106mm Recoilless Rifle was mounted to left and slightly to the rear of the commander’s station, and manned by a crew that stood in the hatch on the rear hull deck.  The on-board ammunition was a modified Carl Gustav M2 ammunition box (typically plywood with thin sheet aluminum sides), but most crews of these vehicles carried more boxes of ammunition in the passenger area.  As with the FSV, the Recoilless Rifle carrier could carry a small dismount squad, but generally didn’t, to allow more ammunition to be carried.  The M2HB machinegun at the commander’s cupola was retained.  As they were stopgap vehicles, they were withdrawn from service soon after the Australians left the Vietnam War.

The M113A1 MRV

     After the Vietnam War, the Australians did not get rid of their M113A1s; in fact, they continued to modify and improve them (and heavily-modified versions are still in service today).  As the FSV was always considered an interim version, a new version was fielded by the Australian Army in the late 1970s.  It was essentially the same idea as the FSV, but used the turret of the Scorpion instead of the Saracen’s turret.  The Scorpion turret used the same caliber gun, but fired its ammunition at a higher velocity.  At first called the M113A1 FSC (Scorpion Turret), the name was later changed to the MRV (Medium Reconnaissance Vehicle, reflecting its intended primary role as a scout vehicle than simply an infantry support vehicle.  Other than the more powerful main gun, the Scorpion turret offered night vision for the gunner and commander, radiological shielding for the turret, more space for radios, and a laser rangefinder/ballistic computer combination.  The MRV also has a collective NBC system for the crew.  The MRV can also carry a small dismount squad.  Though the turret is not heavily armored, some appliqué armor has been added to the hull.  As with the FSV, the MRV requires flotation cells to be added to the sides and a special trim vane in order to swim, but it otherwise retains the amphibious capability. Suspension upgrades, engine upgrades, and some other improvements made for a lighter vehicle than the FSV, with an attendant slight increase in speed, maneuverability, and fuel economy.

     MRVs were later given upgraded armor on the hull floor by adding titanium plates to the underside of the vehicle.  This had a similar to the Vietnam-era belly armor upgrades, but was lighter in weight.

 The LAND 106 Project

     As early as the mid-1980s, the Australian Army sought to upgrade their still-useful M113A1s to a more modern configuration.  They did not feel that outright replacement was necessary; most of their M113A1 fleet had been well-taken care of and was still quite serviceable.  Unfortunately, the projected upgrade program ended up scuttled due to lack of funds, and the M113A1-based fleet continued to soldier on only with what money was needed to keep the fleet going.

     In 1996, the issue of upgrading the M113A1-based fleet was again taken up by the Australian government.  By this point, the Australian Army had 520 M113A1-based vehicles of all types.  This led to the LAND 106 project, which aimed to perform major upgrades on 350 M113A1-based vehicles, provide less-comprehensive upgrades on about 50 more, and produce some 50 more vehicles that would be essentially new-build vehicles.  Other M113A1s would be simply rebuilt to extend their useful lifetimes. Much haggling ensued, with little more than prototype and drawing-board work being done; it seemed for a while that LAND 106 would also fall by the wayside.  However, in 2007, the Australian Army finally received the funding it needed, and upgrade work began in earnest in 2007; this work is estimated to be finished between 2010-2013. Though a little of a budgetary hiccup occurred in 2008, the LAND 106 project is now back on track. When finished, the resulting vehicles will mostly be equivalent in capability to the M113A3, and more.  The overall series description for the most-upgraded variants is the M113AS series.  Complete prototypes appeared in 2004, Low-Rate Initial Production (LRIP) began in December of 2007, in order to conduct field testing; Full-Rate Production began in 2007, with initial deliveries beginning in November of 2007. 431 vehicles are scheduled for major upgrades, an additional 81 vehicles scheduled for lesser upgrades.  The upgrades are projected to keep the M113A1-based fleet viable until at least 2020.

 General Upgrade Characteristics

     The most comprehensive upgrades are to be done on the basic M113A1 design. Though work is being simultaneously carried out on several different upgraded versions, work started on the vehicle that would be called the M113AS4.  The M113AS upgrades the engine, transmission, driver controls, and armor, and also adds some new bells and whistles.

     The M113AS is equipped with a 280-horsepower turbocharged diesel engine, designed by MTU of Germany, and conforming to EURO 3 standards for exhaust, efficiency, and environmental concerns. This is coupled to an automatic transmission designed by Renk of Germany that maximizes the power of the engine.  The tracks and roadwheels are also replaced by designs that make the track and roadwheels stronger and lighter. The entire powerpack and drive train are lighter, more compact, and more reliable. The suspension itself is also improved for a better ride and off-round performance. The driver’s control tillers and gas pedal are replaced by a steering yoke and a conventional brake and gas pedal, though it is of more ergonomic design than those of the M113A3.  The pivot steering capability is retained.  The M113AS has additional protection in the form of aluminum and steel appliqué armor, with titanium plate reinforcement for the hull floor.  The interior of the M113AS also has additional protection, including a Kevlar anti-spall liner.  One constant complaint of M113A1 crews was vibration and noise (I can tell you from experience that both are extreme).  This problem has been partially solved with mats made from a special rubber compound that provides both shock absorption and noise abatement.  The mats are designed to fit each variant precisely, allowing them to stay in place with little fastening. The fuel tanks have been removed from the passenger compartment walls, to either side of the rear hull.  The amphibious requirement has been dropped.

     An interesting feature added to the M113AS series is a water distillation and purification unit, which can provide 20 liters per hour of drinking water from local water sources, including salt water.

 The Upgrades

     The M113AS4 may be considered the “base” upgrade, though in many senses none are really the base, and most versions of the M113AS have been upgraded simultaneously.  The M113AS4 is the basic APC variant, and the most numerous member of the LAND 106 program. This version is a stretched model, with six roadwheels on each side and 66.6cm of extra length.  Atop the M113AS4 is a turret designed by Tenix that is equipped with a heavy machinegun.  This provides much more protection than the previous commander’s station, as well as much better vision equipment. The turret has electric traverse and stabilization for its machinegun as well as an assist from a laser rangefinder and a ballistic computer.

     The M113AS3 is essentially the same, but is not stretched.

     The remaining members of these large-scale upgrades include a fitters vehicle, a light ARV, and a mortar carrier.  None of these will be discussed in this section.  However, three other versions exist, all based on the M113AS4: the M113AS4-AA armored ambulance, the M113AS4-ACV armored command vehicle, and the M113AS4-ALV armored logistics vehicle.

     These three variants of the M113AS4 are armed, but do not have the turret of the APC version of the M113AS4.  Instead, they have M2HBs at the commander’s station surrounded by gun shields.  The M113AS4-AA can carry up to 4 stretcher-borne patients or up to 8 seated patients.  It has all the usual medical supplies one might expect from an armored ambulance (the equivalent of 12 personal first aid kits and four doctor’s medical bags), but also has a defibrillator, four oxygen sets to assist patients in breathing, a refrigerator for perishable medical items, and a small heater to warm blankets and therefore assist in treating hypothermia.  The M113AS4-AA also has heating plates to cook warm meals or warm already-existing foods, and warm liquids, and a 30-liter water tank.

    The M113AS4-ACV is equipped with up to six radios (generally a mix of medium and long-range radios) and one very-long-range AM-based radio.  The vehicle has map boards, various supplies to issue orders and plot movements, a small-but-tough laptop computer, and-held observation devices (generally an image intensifier and a thermal imager, a laser rangefinder, as well as several pairs of binoculars), a small, 20-liter water tank, and various items for its command vehicle role.  The observation devices are included in the price below, but not specifically listed.

     The M113AS4-ALV – well, it’s essentially a large, armored, tracked truck, designed specifically to replenish troop supplies at combat positions.  As such, the cargo area is basically wide open, though it does have lockers on the walls to help keep supplies from flying around the interior while the vehicle is moving. It does not have troop seats; it is essentially a large open space surrounded by armor.  It does, however, have a small crane able to handle 2 tons to help load and offload supplies.

     Some other M113A1-based vehicles have had a lesser array of upgrades; for example, some MRVs have had an engine upgrade, along with a transmission change; some also have a modernized driver’s station.  Some of the M113A1-based vehicles now in Australian service are simply not slated for any upgrades and will eventually leave service.

     Twilight 2000 Notes: The Australians still had most of their modified M113A1s, though most were in storage, kept in usable condition.  Modified M113A1s that were modified to carry weapons like recoilless rifles no longer had their weapons, weapon mounts, or ammo racks mounted, though these items were kept separately and maintained at the same facility.

     Vehicles like the LRV and MRV were kept in active service, as were M113AS3 and S4-based M113s, Some half of the remaining weapons carriers were restored to their former duties, while the other half were refitted and turned into “stock” M113A1 APCs and M113A1 ACAVs.  Most of them were fitted with belly armor kits.  The LRVs and MRVs were refitted with their belly armor and hull floor upgrades, as they were not normally fitted in peacetime.  This work was done from 1994 to 1996.

*Hull floor armor for this version is 4.

**Hull floor armor for this version is 5.

***Up to eight seated or 4 stretcher-borne patients or personnel.