Most of us here should know about the M24 Chaffee, M41 Walker Bulldog and the M551 Sheridan however few know about how the US Army got carried away in designing light tanks in this time frame of the late 1940s to the mid 1950s.
First off I would like to discuss the “missing link” between the M24 and the M41, the T37. Most of you should know a little about the T37 by WoT. It is the source for the M24's upgraded turret, even though it is too large for the Chaffee's turret ring(the US did have plans to enlarge the T24/M24 turret ring though which would allow the T37's turret).
Now to discuss the T37. In Jan. 1945 the Army Ground Forces Equipment Review Board and the War Dept. Equipment Review Board both decided the M24 wasn't fit. They proposed a 25t vehicle that had superior firepower & mobility compared to the Chaffee. They called it the T37.
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Development began in 1946 and a pilot was produced in 1949. The T37 was split into 3 “phases”. Phase I was the turret and gun combination we see on the Chaffee in WoT. Phase II was mounted with a deadlier T91 76 mm gun(same gun as on the T71 LT) with a Vickers fire control system and became redesignated the T41 (direct precursor to the M41). Phase III was an autoloading variant which wasn't built due to the Korean War. Some more advanced features of the T37 such as the rangefinders, the FCS and autoloaders were never fully developed due to the war in Korea. In 1950 orders were given to Cadillac to produce 100 T41E1s which became the famed M41 Walker Bulldog.
The M41 Walker Bulldog itself was planned to be up-gunned before it was planned to be replaced. The T49 project saw the T41(the M41's prototype) transform into a 90 mm smooth bore wielding vehicle with a punch. This project was started in Jan. of 1950 to make sure the T41/M41 had enough firepower to deal with heavily armored Soviet Vehicles such as the IS series, since the 76 mm gun was perfect against T-34s.
The project was given the name T49. The gun was a low pressure weapon that fired fin-stabilized shaped charges. Very shallow rifling was added. The weapon was called the T132E1. These guns fired 3 shell types: HEP(High Explosive Plastic), HEAT, and HE. This was mounted in a new turret design.
Two T49s were shipped in May, 1954 to Aberdeen and remained there for a little over a year in tests. It was found satisfactory but the gun limited the types of ammo available. It was also deemed by the US to not be worth the time to develop. Speed was also decreased from the M41.
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Another up-gunning project for the M41 Walker Bulldog is likely to appear in WoT, this was a proposal by Cadillac to mount the M41 90 mm gun in the Bulldog in 1956. Expect this as the top gun. I might delve further into the M41 Walker Bulldog's development and history later on.
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In the beginning of the M41's production the US saw it as an interim design and immediate began programs to replace it.
A design from the Detroit Arsenal was the first of many proposals/prototypes. It was a 17 ton vehicle(as seen below) that had the same 76 mm gun as the M41. With a rear turreted design this proposal led the way for the L series of proposals. These proposals were created during the 1st Questionmark conference in April of 1952. I personally find the rear mount odd in American tanks due to the decrease in gun depression that goes with it, however they still seem to retain some of that comfort we all associate with American tanks. I would imagine -8 depression would be possible.
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L-1 had the same 76 mm gun and was the basic 17t design, varying little from the Detroit Arsenal 17t tank, it had ~250 hp engine. The L-2 was a variant using a larger T139 90 mm gun.
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The L-3 and L-4 had a similar layout but the hull was slightly different. Both used the T139 gun. A more powerful 440 hp engine was planned. Armor for the L-3 was the same as the M41. The L-4 had double those values.
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The L-5 and L-6 were T140 105 mm armed tanks. They had the same engine and armor as the L-3. A larger turret rings were used to accommodate the large T140 gun. Warning: This design is fugly.
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The Last of the L Series of vehicles to be proposed at the Questionmark Conference was the L-7. The L-7 was armed with the 76mm gun T91E3 in an oscillating turret. It weighed ~17 tons and, like most of the other concepts, its armor was equivalent to the M41's. It used the ~250 hp engine found on the L-1 and L-2. The L-7 was equipped with an autoloader.
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All in all the L Series was quite experimental. All had frontal engines and drives for the sake of crew protection. The front drive also allowed the vehicles to be shorter than rear drive designs. A unique features of the L Series were that external fuel were easily dropped in case of emergency, a grill system protected against napalm attacks and a .50 caliber MG was proposed which is eerily similar to the StG 44 Krummlauf was to be fitted in the turret.
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Do I expect these tanks in WoT? Well the T37 should be a tier 6 between the M24 and M41 in the future IMO; I have doubts it will though since it is very much like the Walker Bulldog. The T49 is tricky because of the smooth bore issue, I would doubt it will be in WoT unless they allow smooth bore guns. The L Series of vehicles should be in WoT too. I would like to think they would be good tier 6, 7 and possible tier 8 lights. Hope you'll enjoyed it and by the way there is a lot more US light tank prototypes to come among other things.
Source of information: Sheridan: A History of the American Light Tank vol. 2 by R. P. Hunnicutt.