Attempting to modernized its extensively outdated armored corps consisting of World War 2-era M4 Sherman Medium Tanks and M3/M9 Half Tracks, the Argentine government sought new alternatives entering into the 1970s. Since the nation lacked the historical base needed for indigenous design and development of an expensive tracked vehicle program, they commissioned the German concern of Thyssen-Henschel (now Rheinmetall Landsysteme of Kassel, Germany) in 1974 for the task. Key to the Argentine Army requirement was development of a frontline Light/Medium class combat tank and an infantry fighting vehicle (IFV) utilizing the same chassis and powertrain to keep costs under control.
Thyssen-Henschel responded by outfitting the existing German Army Marder IFV for the roles - the combat tank to feature a full-sized traversing turret and large-caliber armament and the IFV to sport a more compact turret with autocannon and fighting compartment for passengers. The Germans - with Argentine input - developed three prototypes of each vehicle and these underwent extensive tests and trials while still in Germany. Upon successful completion of the tests, the vehicles were then shipped to Argentina to which the TAMSE (Tanque Argentino Mediano Sociedad el Estado) factory was established at Buenos Aires for serial production. Some 70% of the vehicle was Argentine with the remainder of components being German in manufacture with final assembly in Buenos Aires.
The initial Argentine Army order called for 512 vehicles (200 TAM tanks and 312 VCTP IFVs) to stock its inventory though budgetary constraints forced the order to be cut to 350 units and, even then, only 250 units were completed (150 TAM tanks and 100 VCTP IFVs). The Argentines designated the new combat tank as the "TAM" (Tanque Argentino Medium = "Tank, Argentine, Medium") while the IFV became the VCI (Vehiculo Combate Infanterie = "Infantry Combat Vehicle") with seating for 12 and armed with the Rheinmetall RH-202 20mm autocannon (the VCI designation was eventually evolved to become VCTP (Vehiculo de CombateTransporte de Personal = "Personnel Transport Combat Vehicle")).
From these developments, several major variants arose, each fulfilling desired combat roles within the Argentine Army and utilizing the chassis of the TAM tank though all seeing substantially limited production totals. This included the 155mm-armed VCA 155 (Vehiculo de Combate de Artilleria de 155mm = "155mm Artillery Combat Vehicle") mating the chassis of the TAM tank with the turret and gun of the Italian OTO-Melara Palmaria Self-Propelled Gun (SPG) platform, the VCRT Armored Recovery Vehicle (ARV) (sans turret) and the VCL (Vehiculo de Combate Lanzacohetes = "Rocket Launcher Combat Vehicle") TAM-based rocket projector vehicle with Israeli-designed launcher and rockets. A command vehicle - the VCPC (Vehiculo de Combate Puesto de Mando = "Command Combat Vehicle") is also recognized and based on the VCTP.
The TAM is a very conventional combat system and its Marder IFV origins are clearly recognizable in the chassis and hull sections. The hull sports a well-sloped glacis plate leading up to the hull roof. Sides are near-vertical with slight sloping while the rear panel slopes inwards as well. The turret is set at the rear of the design with extensive overhang noted. Unlike other frontline combat tanks, the TAM features its engine in a front right compartment more akin to modern IFVs. The turret is of a low-profile design with the gun barrel protruding out of the frontal panel as normal. Turret frontal and side panels are slightly sloped for basic ballistics protection. The running gear consists of six double-tired road wheels to a track side with three track return rollers featured (these sometimes shrouded by the optional saw-tooth side skirt panels for increased protection). The drive sprocket is at the front of the hull with the track idler at the rear. Armor is of steel construction and an NBC (Nuclear, Biological, Chemical) system is standard. The vehicle is crewed by four standard operating personnel including the driver (front-left hull), commander, gunner and loader (all in the turret, mid-hull section).
The TAM tank is powered by a German MTU-brand MB 833 Ka 500 series supercharged 6-cylinder diesel engine developing 720 horsepower at 2,400rpm. This allows for a maximum road speed of 46 miles per hour with an operational range of 580 miles. An optional external fuel drum can be mounted to the hull rear panel for an increase in operational ranges. The hull is suspended atop a conventional torsion bar suspension system which provides the needed cross-country travel qualities.
Main armament is centered around the turret-mounted 105mm FM K.4 Modelo 1L main gun (essentially the British Royal Ordnance L7A1 rifle tank gun series) which can be locked in place with an inverted Vee locking assembly during transport. This is supplemented by a 7.62mm coaxial machine gun next to the main gun. An optional 7.62mm machine gun is fitted at the commander's cupola as an anti-aircraft / anti-infantry deterrent. 2 x 4 electronically actuated smoke grenade dischargers provide a makeshift smokescreen for the vehicle and crew. There are 50 x 105mm projectiles carried as well as 6,000 x 7.62mm rounds of ammunition.
The TAM was introduced into Argentine Army service in 1983 and maintains an active presence in its inventory to date (2013). Production of initial batch models spanned from 1979 into 1991 which initially produced a batch of 150 TAM tanks and 100 VCTP IFVs while a second batch was ordered from 1994 to 1995 and this added 50 TAM tanks and 116 VCTP IFVs according to sources. A modernization program has since been undertaken in 2010 to bring the tracked family of vehicles up to modern fighting standards. The Israeli concern of Elbit Systems was handed the charge and key to the upgrades will including the fitting of a 120mm L44 series main gun (the Rheinmetall 120mm smoothbore) to help increase the tactical value of the TAM tank significantly. Modernization is expected to continue into 2013. The Argentine Army currently fields 200 TAM tanks and 216 VCTP IFVs (some of the latter being command tanks).
The TAM tank provides a solid combination of speed and mobility with adequate firepower and protection to meet the threats as posed by its neighbors in a potential war scenario. It is still outclassed by the latest generation of Main Battle Tanks around the globe but nevertheless fulfills a need at cost. Its chassis has proven reliable and modular in the grand scope of Argentine Army needs for both the short and long term and will continue to service the nation for a decade or more longer. Foreign interest in the German-Argentine product has been noted though there have been no buyers to date and this has inevitably forced the closing of the TAMSE factory in 1995.
The only notable combat deployment of TAM tanks was during the Yugoslavian was of the 1990s when Argentine TAM tanks were operating in the peacekeeping role under the banner of the United Nations.