Sunday, 25 October 2015

Red, White, Black and Blue, Part 2: In Search of the Game Changer

Part 1: http://ritastatusreport.blogspot.cz/2015/10/red-white-black-and-blue-part-1-pattons.html

Author: Ck16

(Above: M60E1)

Hello once again!

Welcome to part two of three articles covering the development of the American medium tanks of post World War II to the early 1960’s, and how this pertains to WoT. We continue off with the cancellation of the T54 project to find a way to mount a 105mm gun on a medium chassis. It had already been decided by the US that the M48 with it’s 90mm M41 was not enough for the modern battlefield and a successor was wanted, but it was still undecided what the identity of the next tank to serve the US Military would be. The gears would continue to turn and more developments were pushed forward to find the answer to the Medium tank “issue".



T95: The next step?

In June 1954 the program for a lighter and more powerful medium tank was launched under the designation 90mm gun tank T95 along with the T96 heavy tank. These tanks would incorporate many technical advances in armor fighting vehicles ranging from siliceous-cored armor to hyper-velocity smoothbore guns. The going was slow though due to all of the new innovations took time to fully be developed and the first vehicle would not be finished till May 1957. This variant was the T95E2 with a M48A2 turret on a T95 chassis. That August, the army started take a different view on their tank identification and wanted to narrow it down to two classes of tanks, Reconnaissance/airborne tanks and main battle tanks.

The belief of a main battle tank was that it would have the armor and firepower of a heavy tank able to perform the assault role and the mobility of a medium tank. The T95 in some variant was thought to be the future main battle tank for the US Army. With several developments of the T95 it was found out that the T96 heavy tank turret could fit on the T95 chassis. This eliminated the T96 program as the heavy hull was deemed unnecessary and brought both under the T95 program to create a universal tank. The T95 was produced in several variants each testing a different system of some sort. The major difference between many of them was the use of several different turrets and armaments with several studies carried out from late 1956 to 1957. The armaments planned for testing ranged from the 90mm M41, the British 105mm L7, and the 120mm T123E6(a derivative of the M58 on the M103). As well taking turrets from the original T95, M48A2, T54E2, and T96. All of these different set ups would receive a different designation as seen in the image below but not all of the concepts would be built due to budget and time issues.


(Above: T95 project chart)

The results of several studies on various armaments lead to plans to mount in a M48A2 turret the 105mm T254 that was based off the British 105mm L7 this resulted in a new designation 105mm gun tank T95E5. It was determined that the protection offered by the M48A2 turret was inferior to that of the T95 turret. To rectify this, a plan to mount the 105mm in the T95E1 was made, designated the T95E7. Before either of these variants could be produced however, the program came to an almost complete stop in early 1958. There was a belief that a more cost effective tank could be produced to meet the main battle tank role based and would be based off the M48 design. The reason for this over the T95, was that it would not give enough to be deemed a new full production vehicle. The program would continue for a few more years exploring new variants of the T95 with new engines but it was officially canceled in July 1960. (see [1] pg. 149 & [2] T95 program)

(Above: T95E7)

The Current situation

Step back for a moment and you may have noticed something by now, many of these developments of these tanks were from the late 1940’s to the late 1950’s and it was already clear the M48 was outdated compared to even tanks like the T54 series early on. To put this in perspective a bit to other tier 10’s in World of Tanks. The T-62 entered service in 1961, Leopard 1 came in 1965 when production started, and AMX-30B the first production vehicle was finished in 1966 along with the Chieftain (Mk.1) in the same year. Then there is the STB-1, the test bed for the Type 74, this was completed in 1969. The M48 as you can see is closer to the E-50 concept in age then to the other most recent medium tanks added and one heavy tank (planned) to the game. So what does that leave us with for options, well there is there is the option for the M60. Armored Warfare has it along with War Thunder now, so why not World of Tanks? The M60 entered production in 1959. . . But wait . . .this was used already by Wargaming, as the M60(A0) was given to the Clan War winners in the first campaign and is exclusively their tank now, so strike one! But does this kill an early production MBT for the American tree with a one and done?

XM60: The conception

There were some concerns after the British found out their 20 pounder and the current US 90mm at the time were not capable of penetrating a T-54 acquired during the Hungarian revolution in 1956. This lead to a huge push to get a better armed tank to the US troops in Europe as soon as possible. So with this “crisis”, concepts for the XM60 were thought up and presented to Ordinance. The concepts could be found to be equipped with several different armaments and turrets in the beginning. Ranging from a M48A2 turret with a 90mm M41 to a T95E6 turret armed with a 120mm T123E6 (see images below). Initial plans were pushing for the 120mm T123E6 in the T95E6 turret but before the final call could be made a test was to be held.



(Above: XM60 concepts top, XM60 turret mockup bottom)

M60: The compromise 

The final decision for the armament of the XM60 was to be made after a “shoot off” between several guns in use and being tested at the time. These were the 90mm M41, 90mm T208E9 (smooth bore),105mm X15E8, 105mm T254, 120mm M58 , and the 120mm T123E6. The testing would be held at Aberdeen in October and the results noted. Despite the T123E6 being originally sought out by Ordinance it was deemed to have a reload rate to slow to be effective due to the two part ammunition, and the 105mm T254 based off the British L7 design was chosen for the XM60 program.

 (Above: Different turrets trialed on the M48 chassis and comparison of various US tank guns)

The T254E2 would later be designated the 105mm M68 and placed in a slightly modified M48A2 turret requiring a larger ring for the new T9 commander's cupola and altered to allow the new gun mount for the 105mm. This would be mounted on the new hull design that no longer kept the elliptical nose and was replaced by a wedged shape. It was originally meant for a siliceous cored armor but plans changed and it was kept as cast homogenous steel. There were concerns as well about the fuel economy with the gasoline engine common in the M48, and this was replaced with a Continental diesel AVDS-1790-2 that put out 750hp as well as a new transmission. With these changes the XM60 was officially ordered on 11 December, 1958 but within months the project was pushed further along trying to deploy the 105mm M68 as soon as possible and come 16 March,1959 the project received the designation 105mm gun full track combat tank M60. The 1st pilot vehicle was finished 3 July, 1959. This was delivered to Aberdeen Proving Grounds but with out the new cupola. There it received a T6 cupola off one of the T95 test vehicles for a short while before getting the new cupola that would make it almost identical to the first production vehicles. After initial trials of the M60 concluded, M60’s began to see deployment with US Army-Europe by the end of 1960..The M60 would only be produced from 1959 till the October 1962, when greater prospects loomed on the horizon for the M60.([1] pg.157 - pg.167)

(Above: The M60 "Slick")

M60A1: The coming of a Savior!

Now jump forward a few years the XM60 program was finished up and now designated and in production as M60. But the original concept of the XM60 with the T95E6/7 turret was still desired to improve the M60 further. Thus M60E1 was officially ordered on 29 June 1961. But this program was already going on and was initially approved back in March 1960. Chrysler had fabricated three pilot tanks with the new turret installed on reworked M60 chassis. Along with some other changes to the hull, from general crew comfort features to hydraulic shock absorbers replacing the snubbers used in the first M60’s. These efforts would lead to the M60A1 officially classified on 22 October 1961. There were even further improvements to the hull, increasing the upper front plate from 3.67” (93.22mm) to 4.29” (108.9mm). With these changes, the production of the M60A1 started in 1963 and would last over 20 years with numerous upgrades and modification added. The M60A1 would serve in the US military up until the M1 Abrams series tanks were fully deployed, and upgraded M60A1’s even saw combat in the Persian Gulf during Operation Desert Storm with the US Marine Corps, achieving kill-to-destroy ratios similar to that of the Abrams. To American allies around the world and even today it remains in service. Many have been upgraded with modern technology but the base tank remains a symbol to its strength and versatility, being the American icon that was the backbone of the US Army’s armored divisions for decades.(see [1] pg.159-174)

 (Above: M60 left, M60A1 right)



Sources:

Hunnicutt, R. (1984). Patton: A history of the American main battle tank. Novato, Calif.: Presidio Press.
Hunnicutt, R. P. Abrams. Novato, CA: Presidio, 1990.

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