Throughout the 1950’s until the 1970’s, the Italian Army had been using a variety of American surplus tanks, such as the M26, M47, and M60 and had even manufactured a large number of M60’s domestically under license. Despite various upgrade work on the M47 by OTO Melara, the tank was still outdated and the German Leopard was much better suited to Italian needs and wants. Several hundred Leopards ended up being used by Italy with some supplied directly by Krauss-Maffei and others built domestically under license.
At the same time, work was being carried out on a replacement, or cheaper export version with the ‘Lion’ project which ended at the prototype stage in the late 1970’s. By 1980, with the end of production of the Leopard in Italy, OTO-Melara still wanted to be able to offer a tank for export mainly to Middle-East nations – something expressly not permitted within the terms of the license from the Germans for the Leopard. With the Leopard and Lion manufacturing experience, it is no surprise therefore that the OF 40 possesses more than a passing resemblance to the Leopard 1A4 and does use some components from that tank, although it is not a copy. The German firm even sent engineers to examine the OF 40 in case it was violating their license but were satisfied that it was different enough.
The ‘Carro da Combattimento Medio OF 40’ was the product of the Italian consortiums of OTO Melara SpA (Societa Ligure Piemontese Automobili) of La Spezia, responsible for the bulk of the manufacturing, and Fiat (now Iveco-Fiat), responsible for the automotive components. This is the source of the name. ‘O’ stands for OTO Melara and ‘F’ for Fiat, while the ‘40’ relates to the weight; 40 tonnes. Although commonly referred to as a ‘Main Battle Tank’ (MBT), the sales literature from OTO-Melara categorizes the tank as a ‘Medium Battle Tank.’ The first prototype of the tank was completed by 1980 and very quickly passed trials and was purchased by the nation of Dubai. Deliveries to Dubai began in 1981.
OF 40 Mk.1 as advertised circa 1980. Source: OTO Melara
OF 40 Mk.1 Source: OTO Melara
The main armament is the OTO-Melara 105mm L/52 rifled main gun mounted in the turret with a semiautomatic falling-wedge type breech, spring recuperator and concentric buffer. This gun is not the same as the Royal Ordnance 105mm gun L/52 gun but it is very similar and the ammunition is compatible. Alongside this is a 7.62mm FN MAG coaxial machine gun, and a second 7.62mm FN MAG machine gun mounted on the turret roof for anti-aircraft protection (the location of which changed at least once during development) and a battery of 4 smoke projectors on each side of the turret. The 105mm gun can fire High Explosive Anti-Tank (HEAT), High Explosive Squash Head (HESH), and Armor Piercing Discarding Sabot (APDS) ammunition all fired electrically. The gun, being electro-hydraulically operated, returns to battery for reloading automatically after being fired. Other NATO compliant 105mm ammunition can also be used such as Smoke and Canister although both the commander’s sight and gunner’s sight only carry ranging scales for APDS, HEAT, and HESH.
Turret roof of OF-40 Mk.1 showing the commander’s panoramic sight and alternate position of the AA machine gun. Source: Orbis publications
The muzzle velocity for the APDS shell was 1,470m/s, 1,170m/s for the HEAT and 730m/s for the HESH, and the gun could be fired at a maximum rate of 9 rounds per minute. Elevation and depression for the main gun was from -9 degrees to +20 degrees. Maximum range the gun was sighted for is 6000 meters.
OF 40 Mk.1 during trials firing the 105mm main gun. Source: OTO Melara
Upgraded OF 40 Mk.1 as fitted with upgraded optical camera. Note the older (Mk.1) style rear stowage. In this arrangement, this Mk.1 was advertised as a Mk.2. Source: Janes
The coaxial machine gun could, if needs be, be used to assist in ranging as it would be matched ballistically to the main gun. Nineteen (19) shells for the main gun were carried in the turret along with 2500 rounds for the machine guns. A further 42 rounds for the main gun were carried in an ammunition rack in the front left of the hull. An additional 3000 rounds of ammunition for the machine guns were carried in the hull. An additional useful feature of the vehicle was that the commander could take over control of the gun with his own equipment. He could target, aim, and fire the gun independently of the gunner.
OF 40 Mk.1 in the desert Source: Squadron/Signal publishing
The turret was made from plates of welded rolled homogeneous steel armor plate using spaced armor in critical areas. The turret rotated on its ring on steel ball bearings and was capable of being traversed 360 degrees at a speed between 0.5 degrees per second up to 22.5 degrees per second.
OF 40 Mk.1 on display showing the angular hull form and rubber side skirts to good effect. Source: OTO Melara
The hull was made from welded rolled homogeneous armor steel with spaced armor in critical areas and with the crew compartment divided off from the engine area. The driver was seated in the front right with the ammunition stowed in the hull to his left.
The seven wheel stations each have double wheels and are connected via swing arms to torsion bars. Drive is delivered to the steel tracks by a rear drive sprocket and the rubber block track is carried on its return by 5 support rollers.
The first-three and last-two swing arms are fitted with telescopic dual action hydraulic shock absorbers and conical springs, preventing the wheels from deflecting too far and causing damage to the bar or arm. The OF 40 also features three separate braking systems, service, braking, and emergency, respectively.
The gunner is equipped with a laser range finder and a x8 optical telescope and the commander’s position is fitted with a panoramic periscope with an optional French SFIM VS 580-D stabilized sight for target surveillance and acquisition. Episcopes are also provided for the crew with 8 for the commander, 1 for the gunner, 2 for the loader, and 3 for the driver. An additional night driving sight is available for the driver.
The OF 40 is equipped with a licence built Fiat V-10 Diesel engine delivering 850 hp connected to a fully automatic gearbox with hydraulic torque converter. At maximum output, it delivers 295 kg-m of torque. The gears are electrically selected with options for 4 forward and 2 reverse gears. In the event of an electrical failure, a manual override can be used for second gear. This combination delivers a power to weight ratio for the OF 40 Mk.1 of 19.3 hp/t. The 1000 litres of diesel held onboard were sufficient for up to 600 km of driving on a road with a top speed of 60 km/h.
Rear view of OF 40 Mk.1 showing the arrangement of exhausts. Source: Janes
The hull was fitted with an automatic fire extinguishing system and an escape hatch in the floor. Nuclear Biological and Chemical agent filters and an overpressure system were fitted along with a fume extractor system for the crew. Bilge pumps were also fitted to ensure the tank could clear out any water coming into the hull.
OF 40 Mk.1 during trials on the climbing ramp. Source: OTO Melara
Coming down the ramp affords an excellent view of the hull of the OF 40 Mk.1. Source: OTO Melara
OF 40 Mk.1 during desert trials. Source: OTO Melara
The OF 40 was a capable tank, better than the basic Leopard 1, and free from any export problems. It was an ideal tank for Italy to try and sell. The OF 40 was offered for sale including some local production to Spain and Greece, and was demonstrated in Egypt too. Despite all these efforts and the interest it generated, only the Gulf nation of Dubai purchased any. No Mk.1 examples are known to be in service today as all Mk.1’s delivered were upgraded to Mk.2 status. Only 18 Mk.1’s were built and the Mk.1 is no longer offered for sale.
OF 40 Mk. 1 Main Battle Tank, specifications
|Dimensions||Length gun forward – 9.22m
Length gun rear – 8.11m
Width with track guards on – 3.51m, with armoured track guards off – 3.35m
Height to top of turret – 2.45m
|Total weight||43 tonnes maximum when fully laden for combat, 40t when laden for transport|
|Crew||4, commander, gunner, and loader, in the turret, and a driver in the hull positioned on the front right|
|Propulsion||850hp Fiat Diesel engine with automatic transmission delivering 19.3 hp/t|
|Suspension||Torsion bar suspension with hydraulic adjustment|
|Top speed||60 km/h|
|Operational maximum range||600km (road)|
|Armament||105mm L/52 rifled gun with 61 rounds, coaxial 7.62mm machine gun and 7.62mm anti-aircraft machine gun with 5500 rounds.|
|Armor||Rolled homogeneous armor steel + spaced armor|
Links, Resources & Further Reading
OF 40 Mk.1 Manual – Oto Melara April 1981
War Machine Magazine Vol.1 Issue. 1 1983
Modern Armor, Pietrangelo Caiti
Janes Armour and Artillery 1985
Illustration of the OF 40 Mk. 1 by Tank Encyclopedia’s own David Bocquelet