Many tanks can trace their design to an earlier vehicle, and there are often clear ‘families’ of tanks that have evolved through generations.
An excellent example of this is the American Cold-War era Patton family, which originated in the M26 Pershing, and ran through the M46, M47 and M48 before culminating in the long-lasting M60. The Tank Museum has an example of each of these in our collection and together they tell the story of over 40 years of tank development and service.
The Origin of the Pattons
The Patton family begins with the M26 Pershing, which entered service in 1945 and was used in small numbers in the closing days of the Second World War.
After the war the Americans stopped all tank development for three years, and manufacture for five. This meant the Pershing would be obsolete before any replacement was ready. An upgrade was implemented to bridge the gap.
This was named the M46 Patton. Around half the 2,202 M26s were remanufactured into M46s, and they were joined by 370 newbuild M46A1s.
The main change was a new, more compact, but more powerful, powertrain. The new engine would be the Continental AV-1790 (petrol at this point), along with an Allison CD-850 transmission. This, in some form or other, would be common to all the Patton family.
There are subtle, but clear differences between the two tanks. The most obvious is the fume extractor at the end of the M46’s 90mm gun barrel. In addition, the M26 has a centrally positioned exhaust coming out of the engine bay whereas the M46 has exhaust mufflers on the back of the track guards. It also has a small idler wheel behind the larger road wheels.
The M46 was never intended to be the US Army’s next tank. There weren’t enough of them and it would soon be outdated. Unfortunately, the replacement programme, called T42, ran into two problems. The first was delays with the vehicle due to mechanical issues. The other was the outbreak of the Korean War in mid-1950. The Army needed its new tank sooner, but it was going to take longer.
The result was a new member of the Patton family, the M47. This was explicitly intended to be a stopgap. It took the T42’s turret and fitted it to what was essentially the M46’s hull. The turret featured a more powerful 90mm gun and a new stereoscopic rangefinder. Together these would make the tank much more lethal.
The M47 was accepted in April 1952, less than two years after it had been ordered. Production lasted just over 18 months, with 8,576 built.
The T42 itself never came together and was cancelled in 1954. By this time the stopgap M47 had a more permanent replacement.
M48s and M60s
The M48 was perhaps the definitive Patton. The first pilot models were built in late 1951, deliveries began in mid-1952 and it was accepted by the Army in May 1953.
The M48 had much thicker armour than the M47, and it was easier to manufacture. Its 90mm gun was aimed by a more capable rangefinder than the M47’s, making the whole system much more accurate.
A major problem with all the Pattons so far had been inadequate cruising range, as little as 70 miles on the M48A1. The M48A2 of 1955 was fitted with the more compact AVI-1790 engine. This freed up space for almost twice as much petrol, increasing range to 160 miles.
In addition, the capable but challenging to use stereoscopic rangefinder was replaced with a coincidence model. In theory it was less accurate, but this was more than made up for by being far easier to use. The M48 was very successful, with 12,942 built up to 1959.
When it came to replacing the M48, the US Army considered two options. The first was to upgrade it with a diesel AVDS-1790 engine, siliceous cored armour and a version of the British 105mm gun called the M68.
The other was a completely new tank, the T95. Unfortunately, as with so many of the Patton’s intended replacements, the T95 had a laundry list of problems and in July 1960 it was cancelled. The upgraded M48 was adopted in March 1959, although it was given a new name – the M60 – and was, officially at least, never called Patton.
The easiest way to tell the difference between an M48 and the original M60 is from the front. The M68 gun has no T-shaped muzzle brake and the fume extractor is now halfway down the barrel. The front of the hull on the M60 has a flat nose with a straight front. This was because the siliceous cored armour needed to be fitted in flat panels. Ultimately, however, this armour was never actually adopted.
An M60A1 is much easier to spot. It has a redesigned turret with cutaways under the front. The turret was also longer, giving more internal space, and it had thicker armour.
The M60 was also considered a stopgap, but several 1960s replacement programmes, including, most famously, MBT-70, were failures and it was forced to soldier on. This meant that by the early 1970s they, and the surviving M48s, would need upgrading.
Upgrades and Replacement
Upgraded models of both the M48 and M60 would be introduced over the next decade, with enhancements to improve firepower and mobility.
The M48A3 introduced in 1963 was fitted with an improved fire control system and the diesel AVDS-1790 engine. This improved fuel efficiency and took its cruising range to 300 miles. From 1975 the M48A5 added the 105mm M68 gun as on the M60, and this served with second line units until May 1987.
The M60A1 saw a dizzying series of improvements throughout the 1970s. The Add-on Stabilizer, or AOS, which allowed accurate firing on the move, was followed by the Reliability Improved Selected Equipment or RISE package for the engine, then by the PASSIVE night vision equipment that replaced the infra-red searchlight. The addition of a laser rangefinder, a new fire control system and a thermal night sight resulted in the ultimate M60A3 TTS of 1979.
By this time the US Army had been able to develop a successful replacement – the M1 Abrams, and production of the “stopgap” M60 ended in 1987 after 28 years and 13,634 tanks.
After a final swansong in the hands of the US Marine Corps during the Gulf War of 1990-91, the last of the Patton tanks in US service were retired in May 1997.
