The M60 Patton is a main battle tank (MBT) introduced in December 1960. With the United States Army's deactivation of their last (M103) heavy tank battalion, the M60 became the Army's primary tank during the Cold War. Although developed from the M48 Patton, the M60 series was never officially classified as a Patton tank, but as a "product-improved descendant" of the Patton series. On 16 March 1959, the OTCM (Ordnance Technical Committee Minutes) #37002 officially standardized the vehicle as the 105 mm Gun Full Tracked Combat Tank M60.
The M60 was criticized for its high profile and limited cross-country mobility, but proved reliable and underwent many updates over its service life. The interior layout, based on the design of the M48, provided ample room for updates and improvements, extending the vehicle's service life for over four decades. It was widely used by the U.S. and its Cold War allies, especially those in NATO, and remains in service throughout the world today despite having been superseded by the M1 Abrams in the U.S. military. Egypt is currently the largest operator with 1,716 upgraded M60A3s, Turkey is second with 866 upgraded units in service, and Israel is third with over 700 units of Israeli variants.
During the Hungarian Revolution of 1956, a Soviet T-54A medium tank was driven onto the grounds of the British embassy in Budapest by the Hungarians. After a brief examination of this tank's armour and 100 mm gun, British officials decided that the 20 pounder was apparently incapable of defeating it. There were also rumours of an even larger 115 mm gun in the works. Hence there was a need to adopt a 105 mm gun, which emerged as the famed Royal Ordnance L7.
This information made its way to the United States, where the Army had been experimenting with a series of upgrades to their M48 Patton tanks. Most of these were relatively minor upgrades, and all of them retained the Patton's T-48 90 mm gun. Most experiments were concerned with improvement in armour and the introduction of a variety of autoloader systems and upgraded rangefinders. The British reports led the Army designers to choose the L7 for future work on their own tanks, and a somewhat hurried program to develop a platform for the L7 followed.
M60A1 tank of the U.S. Army maneuvers through a narrow German village street while participating in the multi-national military training exercise,REFORGER
In 1957, plans were laid in the US for a tank with a 105 mm (4.1 in) main gun and a redesigned hull offering better armor protection. The hull was a one piece steel casting divided into three compartments, with the driver in front, fighting compartment in the middle and engine at the rear.
The resulting M60 series largely resembles the M48 it was based on, but has significant differences. The M60 mounted a bore evacuated 105 mm main gun, compared with the M48's 90 mm (3.5 in), had a hull with a straight front slope whereas the M48's hull was rounded, had three support rollers per side to the M48's five, and had road wheels constructed from aluminum rather than steel, although the M48 wheels were often used as spare parts.
The improved design incorporated a Continental V-12 750 hp (560 kW) air-cooled, twin-turbocharged diesel engine, extending operational range to over 300 miles (480 km) while reducing both refueling and servicing. Power was transmitted to a final drive through a cross drive transmission, a combined transmission, differential, steering, and braking unit.
The hull of the M60 was a single piece steel casting divided into three compartments, with the driver in front, fighting compartment in the middle and engine at the rear. The driver looked through three M27 day periscopes, one of which could be replaced by an infrared night vision periscope. Initially, the M60 had essentially the same clamshell turret shape as the M48, but this was subsequently replaced with a distinctive "needlenose" design that minimized frontal cross-section to enemy fire and optimized the layout of the combat compartment.
The M60 was the last U.S. main battle tank to utilize homogeneous steel armor for protection. It was also the last to feature an escape hatch under the hull. (The escape hatch was provided for the driver, whose top-side hatch could easily be blocked by the main gun. Access between the driver's compartment and the turret fighting compartment was also restricted, requiring that the turret be traversed to the rear).
Originally designated the M68, the new vehicle was put into production in 1959, reclassified as the M60, and entered service in 1960. Over 15,000 M60s (all variants) were constructed.
In 1963, the M60 was upgraded to the M60A1. This new variant, which stayed in production until 1980, featured a larger, better-shaped turret and improvements to the armor protection and shock absorbers. The M60A1 was also equipped with a stabilization system for the main gun. However, the M60A1 was still not able to accurately fire on the move, as the system only kept the gun pointed in the same general direction while the tank was traveling cross country. It did however enable the coaxial machine gun to be brought to bear while moving.
In 1978, work began on the M60A3 variant. It featured a number of technological enhancements, including smoke dischargers, a new flash-lamp pumped ruby-laser based rangefinder (AN/VVG-2) that could be used by both commander and gunner, and an M21 ballistic computer, and a turret stabilization system.
M60A3 main battle tank moves along a street in Germany during Exercise REFORGER '85.
Late production M60A3s omitted the commander's cupola (Israel Defence Force armor doctrine required tank commanders to fight commander-exposed, and it was discovered that non-penetrating hits upon the vehicle could dislodge the cupola from its mount while the commander was in it). The remote-controlled M85 machinegun was relatively ineffective in the anti-aircraft role for which it was designed compared to a conventional pintle mount. Removing the cupola lowered the vehicle's relatively high silhouette. The cupola's hatch also opened toward the rear of the vehicle and was dangerous to close if under small-arms fire owing to an open-locking mechanism that required the user to apply leverage to unlock it prior to closing.
The M60A3 was phased out of US service in 2005, but it has remained a front-line MBT into the 21st century for a number of other countries.
While overall a less advanced tank than the M1 Abrams, the M60A3 did have some advantages over some M1 models:
- The M60A3 TTS had a better thermal imaging system than that of M1 tanks up into the 21st century, when many M1s were upgraded with newer 2nd generation systems.
- The M60A3 had an exterior phone for infantry to talk directly to the crew inside, though this feature was removed from most M60A3's in its later life. This feature was also installed on some M1 tanks with the TUSK upgrade kit.
- The M60A3's diesel engine had lower overall performance, but also it had lower cost, requires less maintenance, and better fuel efficiency.
- The exhaust temperature of an M1's turbine is very high, which makes it dangerous for infantry to take cover behind it. This is not the case with the diesel engine on the M60.
- The escape hatch located under the hull of the M60A3 is not present on the M1 Abrams making it more difficult for the crew to escape a battle-damaged Abrams or evacuate casualties than from an M60A3.
- The M60 series' M68A1 105 mm main gun fires a much wider variety of ammunition than the 120 mm smoothbore on the M1A1 series, because doctrine only required APFSDS and HEAT.
- The M60 series has instrumentation that allows indirect fire as ad-hoc artillery if needed by virtue of having a compass on board.