The M36 tank destroyer, formally 90 mm Gun Motor Carriage, M36, was an American tank destroyer used during World War II. The M36 combined the hull of the M10 tank destroyer, which used the M4 Sherman's reliable chassis and drivetrain combined with sloped armor, and a new turret mounting the 90 mm gun M3. Conceived in 1943, the M36 first served in combat in Europe in October 1944, where it partially replaced the M10 tank destroyer. It also saw use in the Korean War, where it was able to defeat any of the Soviet tanks used in that conflict. Some were supplied to South Korea as part of the Military Assistance Program and served for years, as did re-engined examples found in Yugoslavia, which operated into the 1990s. Two remained in service with the Republic of China Army at least until 2001. In 2010, the last Taiwanese M36 was preserved at Kinmen National Park.
The vehicle is also known by the nickname General Jackson, or just Jackson, named after Confederate general Stonewall Jackson, which was originally assigned to the vehicle by the Ordnance Department in November 1944 for publicity purposes, such as in newspapers, but does not appear to have been used by troops in the field during the war.The name was first used in newspaper articles describing the vehicle that were published nationwide beginning in early December 1944 and continuing into early 1945
Doctrine U.S. combined arms doctrine on the eve of World War II held that tanks should be designed to fulfill the role of forcing a breakthrough into enemy rear areas. Separate GHQ tank battalions would support infantry in destroying fixed enemy defenses, and armored divisions would then exploit the breakthrough to rush into the enemy's vulnerable rear areas. U.S. tanks were expected to fight any hostile tanks they encountered in their attack, but the mission of defeating massed enemy armored counterattacks was assigned to a new branch, the Tank Destroyer Force. Tank destroyer units were meant to counter German blitzkrieg tactics. They were to be held as a reserve at the corps or army level, and were to move quickly to the site of any massed enemy tank breakthrough, maneuvering aggressively and using ambush tactics (charging or chasing enemy tanks was explicitly prohibited) to destroy enemy tanks. This led to a requirement for fast, well-armed vehicles. Though equipped with turrets (unlike most self-propelled anti-tank guns of the day), the typical American design was more heavily gunned, but more lightly armored, and thus more maneuverable, than a contemporary tank. The idea was to use speed and agility to bring a powerful self-propelled anti-tank gun into action against enemy tanks.
Design
With the advent of heavy German tanks such as the Panther and Tiger, the standard U.S. tank destroyer, the M10, was rapidly becoming obsolete, because its main armament, the 3-inch gun M7, had difficulty defeating the thick frontal armor of the newer tanks past several hundred yards. In late summer 1942 American engineers had begun examining the potential of a new tank destroyer armed with a 90mm gun, and produced the prototype 90 mm Gun Motor Carriage T53, which placed the 90 mm gun in an open mounting at the rear of an M4 Sherman chassis. In August 1942, it was agreed to immediately produce 500 vehicles, with 3,500 more later. The Tank Destroyer Force objected, arguing that the design of the T53 was too rushed. The 90 mm Gun Motor Carriage T53E1 proved to be even worse, and the contract was canceled.
In October 1942, the Ordnance Department tested mounting the experimental 90 mm gun T7 into the turret of an M10 tank destroyer. General Andrew Bruce, head of the Tank Destroyer Force, objected to the project, favoring the lighter Gun Motor Carriage M18 'Hellcat', but was ignored. Mounting the 90 mm gun was straightforward, but the gun proved too heavy for the M10's turret, and a new turret was designed with power traverse, and a massive counterweight to balance the gun. The first two M36 prototypes, designated 90 mm Gun Motor Carriage T71 were completed in September 1943. Initially, a request for full production was denied as 90 mm guns were already being studied for use on tanks, but Army Ground Forces approved the project in October 1943, and tests began. The ring mount on the left side of the turret for the .50 caliber Browning M2HB antiaircraft machine gun was changed to a pintle mount at the rear. It was decided that production vehicles would use the chassis of the M10A1 tank destroyer, as the M10A1 had superior automotive characteristics, and significant numbers were available. After testing, an initial order for 300 vehicles was issued. The T71 was designated upon standardization on 1 June 1944 as the 90 mm Gun Motor Carriage M36.
Production
+Production of M36, M36B1, and M36B2Zaloga (2002) p21 Month M36 M36B1 M36B2 April 1944 25 May 1944 100 June 1944 120 July 1944 155 August 1944 100 October 1944 75 50 November 1944 290 93 December 1944 348 44 May 1945 10 50 Post-war 190 674 Total 1,413 187 724
After July 1943, the appliqué armor (add on armor) bosses on the hull side of later M10A1s were omitted as the armor kits were never manufactured. The M36 initially retained the M10A1's "stirrup" gun rest on the rear hull; crews were unhappy about the lack of a travel lock to hold the 90 mm gun in a fixed position when in motion, and many improvised their own from travel locks taken from tanks. A double-baffle muzzle brake was fitted to all vehicles after the first 600, beginning in early November 1944. A folding travel lock better-suited to the 90 mm gun was added to the rear hull at about this time. The gun itself was also modified with a better equilibrator and more powerful elevating mechanism.
As the initial contract was for 300 vehicles, General Motors' Fisher Tank Arsenal produced the last 300 M10A1 tank destroyers in January 1944 without turrets for immediate conversion to M36s, which took place from April to July 1944. The contract was later increased to 500 vehicles, as it was decided that existing M10A1s were also to be converted to M36s. The requirement was later increased to 600 vehicles on 15 May 1944. As it was found that the M10 tank destroyer had struggled against German tanks like the Panther and especially the Tiger during the Normandy campaign, the contract was increased to 1,400 vehicles on 29 July 1944. This caused problems, as only 913 of the 1,413 M10A1s that had been completed could be requisitioned from training units. Due to the lack of M10A1 hulls, it was decided to finish up the initial production run by mounting M36 turrets onto M4A3 Sherman hulls (which had the same engine as the M10A1) with the necessary internal changes; these were designated M36B1. The production of 187 90 mm Gun Motor Carriage M36B1 ran from October to December 1944. From June to December 1944, Massey-Harris converted 500 M10A1s into M36s. From October to December 1944, American Locomotive Company converted 413 M10A1s into M36s. The Army reduced the 1,400-vehicle objective for 1944 to 1,342 vehicles. 350 more conversions were scheduled for 1945; this number was increased to 584. A final batch of 200 M10A1s was converted by the Montreal Locomotive Works in May 1945.
The supply of M10A1s eventually ran out, so it was decided in January 1945 that M10 hulls would be used for all further conversions. American Locomotive Company converted 672 M10 hulls into the 90 mm Gun Motor Carriage M36B2 beginning in May 1945. A further batch of 52 M36B2s was completed by the Montreal Locomotive Works in May 1945.
Combat use
World War II
The first 40 M36s were not shipped overseas until September 1944, and entered combat in October 1944. The US First and Ninth Armies used M36s to re-equip tank destroyer battalions attached to armored divisions. The 703rd Tank Destroyer Battalion began re-equipping on 30 September 1944. The Third US Army used them to re-equip towed battalions. The 610th Tank Destroyer Battalion (Towed) began retraining on 25 September 1944.Yeide (2010) p175 The first tank destroyer battalion to receive the M36 in early September, the 776th, was in transit from Italy at the time and did not use them in combat until October 1944. By the end of 1944, seven tank destroyer battalions had converted to the M36; the M36 had mostly replaced the M10 by the end of the war.
The M36 was well-liked by its crews, being one of the few armored fighting vehicles available to US forces that could destroy heavy German tanks from a distance. An 814th gunner, Lt Alfred Rose, scored a kill against a Panther at 4,600 yards (4200 meters), the maximum range of the telescopic sight. However, the Panther's 82 to 85mm thick glacis platePanther tank's armor thickness chart could deflect shots at certain angles from the 90 mm gun at just 150 yards (137 meters). Testing done in December 1944 by the 703rd Tank Destroyer Battalion concluded that the M36's 90mm Gun would theoretically not be able to penetrate the frontal armor of a Tiger II at any range with the ammunition that was available to them. and that it was tactically viable to engage Panther tanks from the side.Yeide (2010) pp. 174-175Tiger II armor thickness chart
Korean War The M36 was used by the US Army in the Korean War. It could destroy any Soviet-made AFV encountered there. One postwar modification was the addition of a ball-mounted machine gun on the co-driver's side, as in many other armored fighting vehicles of the time. Due to the shortage of M26 and M46 tanks, the M36 became one of the preferred armored vehicles for U.S. Military Assistance Program transfers.Zaloga (2002) p.42
The M36 was classified as a tank by the Republic of Korea Army despite being a self-propelled gun. The South Korean army, which began the war without having a single tank, pushed for the creation of an armored unit and acquired the first six M36s for training in late October 1950. During the war, the South Korean Army received about 200 M36/M36B2s from the US, and operated 9 tank companies. Each company was assigned to the frontline infantry division, and each tank platoon, consisting of five M36s, was attached to an infantry regiment for fire support missions. South Korean M36s retained the latest updates such as the M3A1 main gun and turret top armor. These Korean War GMCs also installed machine gun ball mount for the assistant driver to fight against infantry. The M36 played a powerful role by direct firing at the enemy's position during the battle for high ground. Since it was operated by Koreans, command and communication between infantry and armored units were smooth, and it had a significant effect on boosting morale.
During the Battle of White Horse during 6–15 October 1952, the 53rd Tank Company, assigned to the 9th Infantry Division, contributed to the victory by bombarding the side of the enemy's offensive force and suppressing heavy weapons deployed on the enemy-occupied highlands. In the Battle of Betty Hill on 15–16 July 1953, the 57th Tank Company of the 3rd Tank Battalion provided direct fire support for a platoon defending the highlands overnight, which claimed the lives of 300 communist soldiers. However, the M36 had limitations for large-scale operations due to the equipment already being retired from the U.S. military: spare parts were scarce, and it was difficult to obtain further fully functional vehicles. Servicing became even harder because units were scattered around infantry units. Therefore, the Korean Army began operating in large numbers, forming three armored battalions in early 1953.
Indo-Pakistani Wars