The American Heavy Tank T26E3 was standardized as the Heavy Tank M26 on March 29th, 1945. This stage was preceded by front line trials where the vehicle that the Americans spent so much time and effort building showed itself pretty well. Standardization was a green light for mass production. The end of the war limited the production volume to 2022 units, so the M26 never replaced the Medium Tank M4. It seemed that the end of production would herald in a new tank that had better armour and armament, but that was not the case. The first American post-war tank was the Medium Tank M46 or Patton, effectively a modernized M26.
Modernization instead of revolution
The Heavy Tank M26 (downgraded to a medium in 1946) was a good vehicle, but not without problems. For starters, the thicker armour still did not offer guaranteed protection from German tanks and SPGs. This could be observed in the tank's first battle, when the T26E3 nicknamed Fireball was knocked out by a Tiger tank. Essentially, the tank was protected from the 75 mm Pak 40, KwK 40, and StuK 40. Any larger gun could confidently penetrate its front armour. Another issue was the relatively low power to weight ratio, just 11.96 hp/ton even at maximum engine power. Nevertheless, the tank turned out to be rather quick (showing the highest average speed during off-road trials in the USSR), but also burned a record amount of fuel. There were also issues with the lifespan of the running gear, primarily the road wheels. These issues are rarely discussed in the context of the Second World War, but it was already present. The gumming and destruction of road wheel tired (the first one was destroyed after 753 km of driving) were also observed during trials in the USSR.
|A new medium tank concept designed by the Frederick C. Brecket commission, summer of 1945. The machine guns in turret blisters were later used on the Light Tank T37.
Essentially, the Americans ended up with a good medium tank on the level of the Panther with approximately the same mobility, equal in firepower, and with somewhat less armour. The Ordnance Department, much like the Soviet GBTU, wanted a tank with a more powerful gun and tougher armour. There were projects to modernize the M26 (T26E4 and T26E5), but also more radical ideas. One such idea was presented on June 20th, 1945, by a group from the Armored Medical Research Laboratory led by Frederick C. Brecket. This work was initiated by the AGF (Army Ground Forces), who wanted a medium tank concept that weighed 40.8 metric tons, had 152 mm of frontal armour and 76 mm of side armour. How Brecket's team was supposed to fit such a tank into the prescribed weight limit was a whole separate question. There were also questions about the armament. The Americans must have been impressed by German "fishing rods" and wanted something similar in the 76 mm caliber. Brecket's concept seemed quite odd and distant from reality.
|Comparison of the M26's power pack and the power pack with the Continental AV-1790 engine and CD-850 hydromechanical transmission.
Another commission's project ended in the same way. The War Department Equipment Board, better known as the "Stilwell Council", formed on November 1st, 1945. This commission could not offer anything concrete either. A tank is a combination of various components, and there was an issue with those. The most reasonable suggestion was to start with developing a new family of tank engines, since that was the weakest link at the time.
|Medium Tank M26E2, a test bed for the new power pack. Despite several breakdowns, the idea proved promising.
The biggest issue was with engines for prospective heavy tanks. Existing models were used as test labs. Several engines were tested and the Americans settled on the 810 hp air cooled 29 L Continental AV-1790. This engine belonged to a family of tank engines built at Continental. Various transmissions were also tested on heavy tanks. The Alisson CD-850-1 came out on top. The combination of the Alisson transmission and Continental engine proved itself on the Heavy Tank T30. The CD-850 transmission went through several revisions to make it more reliable. The power pack turned out to be much more compact than the one used on the Heavy Tank T26E3.
|The vehicle can be distinguished from a regular M26 by the mufflers, altered rear plate, and new engine deck.
|Medium Tank T40. A pilot series of 10 tanks was produced before the main Medium Tank M46.
|The rear of the tank changed again and a field telephone box was added.
|The tank with a Continental AV-1790 engine looked completely different from above.
|One of the first production Medium Tanks M46 at the Aberdeen Proving Grounds.
|The first production vehicles were put through intensive trials, much like the T40 prototypes.
|Cutaway of the M46.
|The M46 had a different rear hull than its predecessors. The three access hatches were round, whereas the older tanks had square ones. There were plenty of other differences, including the turret.
|A late production tank, likely already referred to as M46A1.
|M46 disembarking in Korea. This war was the cause of biggest turns of bad luck for the Patton.
|M46 from the 1st USMC Division.
|A tank from the 6th Tank Battalion that ended up in Kubinka in 1951, remaining there to this day.
|Diagram of the M46 tank's transmission. This was the most interesting part of the American vehicle for Soviet specialists. An equivalent system was later tested on the Object 266 tank.
|The M46 in tiger camo were the most famous tanks of the Korean War. These were good looking vehicles, but their combat effectiveness was more questionable.
|One of the variants of 18 inch spotlight installation on the M46.
|An engineering tank equipped with a bulldozer blade and protective netting around the turret.
|The Korean War was the only highlight of the M46's career. The tank was unlucky. The start of the war did not allow it to be built in large numbers or give it time to iron out bugs.
Retirement didn't treat these tanks well. 75 Pershings survive to this day, but only 21 M46 Pattons. The Korean War was the only conflict in which it was used. This war was, in many ways, responsible for the tank's disappointing career.