M24 Chaffee
T17, M8, M8A1, T24, M24, M37, M19, M41, T77, T9, T13, T22, T23, T33, T42, T9, T6E1 and T31
Type:light tank.
Crew:5 men, sometimes reduced to 4.
Armament:one M6 75 mm gun; a coaxial .30 M1919A4 machine gun; a .30 M1919A4; a .50 M2; a 2-inch M3 smoke mortar. Shielding:minimum 10 mm; max 38mm. Dimensions:length:5.49m; width 2.95m; height:2.77 m.
Weight in combat order:18.4 t
Ground pressure:0.79 kg/cm2.
Mass power:12.2 hp/t.
Engine:2 water-cooled Cadillac 44T24 V-8 petrol engines, each developing 100 hp at 3,400 rpm. Performance:road speed:54 km/h; autonomy on the road:160 km; vertical obstacle:0.91 m; clear cut:2.44 m; ford:1.02 m without preparation and 1.98 m with preparation; Slope:60%.
Time in Service:Introduced in 1944 in the US Army. Supplied to many countries including Great Britain (small delivery Still widely used in 1977 France also used the chaffee 4 of them took part in the battle of Dien Bien Phu. Originally, the core of the "group combat light".
Compared to the light tank M5 of which it took the place, the M24 marked a certain progress. On two of the three points without which there is no good armor (firepower and protection), the M24 surpassed all the other light tanks of the Second World War; as for the third imperative, mobility, the machine was as exceptionally maneuverable as the M5. Its 75mm gun almost equaled the Sherman's and outstripped the armament of most medium tanks existing in 1939. Fundamental improvements to the hull and turret shape eliminated vulnerable angles, lowered the silhouette and gave to the shielding a better inclination. Today, everyone considers ease of maintenance to be a sine qua non for building a good tank; it has not always been so and yet the design of the Chaffee gave particular importance to the accessibility of the main assemblies.
The work leading to the assembly of a 75 mm on a light tank began almost at the same time as the project for a medium tank armed with the 75 mm. The T17 75 mm Howitzer Gun Motor Carriage, derived from the M1E3 combat car, was the first step in this direction and later when the need arose for a light tank with the same firepower as the M4 medium tank , the M8 Howitzer Motor Cardage was modified accordingly. Armed with the 75 mm M3, this variant received, although the thing was not quite official, the designation of M8A 1. This material mounted the chassis of the M5, very capable of enduring the fatigue imposed by the firing of the 75 mm, but the M8A1 version lacked the essential qualities of a tank.
The characteristics defined for the new light tank provided for the maintenance of the power unit fitted to the M5A 1, the improvement of the running gear, the limitation of the gross weight at 16.2 t, and armor with a maximum thickness of 25.4 mm and very pronounced oblique planes. The M5A1 light tank had been handicapped by the smallness of the turret which excluded the installation of the 75 mm. It was thought to make a light tank T21 but, with its 21.8 t this machine would have been too heavy. The T7 light tank was examined in detail by the Armored Force. But this machine had been designed to accommodate the 57 mm gun, at the request of the British army, and when the Armored Force asked for a 75 mm, the increase in weight resulting from this modification put the T7 in the category medium tanks. So much so that the standardization under the name of medium tank M7, armed with 75 mm, was accepted then canceled in front of the problems of logistics which inevitably brought the coexistence of two standard medium tanks.
In October 1943, the Cadillac division of the General Motors Corporation delivered pilot models of a vehicle to meet established specifications. Designated T24, this machine was considered satisfactory and 1,000 copies were ordered even before the start of the tests. In addition, an order was also placed for pilot models T24E1, retaining the power unit of the M18 tank destroyer, but this research was to be abandoned. The T24 mounted the 75 mm T13E1 gun (fitted with a T33 anti-recoil mechanism) as well as a .30 machine gun on a T90 mount. The very low weight of the piece was explained by its origin; it derived from the M5 aviation gun and its new designation, M6, simply indicated its use on tanks rather than on aircraft. The T24's twin Cadillac engines were mounted on rails for ease of maintenance - a feature present on the T7 light tank. Indeed, it was because the T24 and the M5A1 had the same power unit that Cadillac was chosen for the mass production of the T24, a cake that the firm nevertheless had to share later with American Car &Foundry and Massey-Harris. The torsion bar suspension of the M18 tank destroyer was used on the T24. It is often believed that this type of suspension was an invention of German tank builders, but in fact the American patent on the torsion bar suspension was granted in December 1935 to W.E. Preston and G.M. Barnes (the future General Barnes, head of the Service of research of the Ministry of Armaments until 1946). Five pairs of road wheels, 63.5 cm in diameter and rubberized, mounted on either side and a front sprocket drove the 40.6 cm tracks. The hull of the T24 was all wrought steel, reaching the maximum thickness of 63.5 rom on the frontal surfaces but, in less critical places, the armor was thinner to meet the criteria of the light tank; a large cover plate in the glacis could be removed to provide access to the controlled differential driving system. Dual controls were available to the driver and his assistant.
In July 1944, the T24 was standardized under the designation of M24 Light Tank, baptized “Chaffee” by the troop, and in June 1945, a total of 4,070 units had rolled off the line. Faithful to the concept of the Light Combat Group, the American manufacturers adapted to the chassis of the M24 other vehicles intended for specialized missions. A whole range of self-propelled guns and mortars were developed, one of the most interesting of which was the T77 Multiple Gun Motor Carriage. This machine mounted a new turret armed with six .50 machine guns on a barely modified standard M24 chassis; in a way, this vehicle heralded the current Vulcan anti-aircraft weapon system, also six-tube. The family also included two service tanks, the T9 and T13, and three tankers. The T22E1 and T23E1 were adaptations of the T22 and T23, which derived from the M5 light tank and are described under this heading. The T33 tanker, a later development, would become the Cargo Tractor T42 by adopting the (medium tank) engine and transmission with torque converters from the Hellcat. The T43 Cargo Tractor was a lighter version of the T42. A bulldozer adaptation, the T9, was developed and adopted under the designation of M4 but remained of limited use. Various buoyancy devices were tested, as in the case of the Hellcat, but none was generalized. Each of the families of machines assigned to the Light Combat Groups included an armored recovery vehicle and the vehicle compatible with the M24 series was the TRV T6E1, abandoned during research. While the M24 was still in the design stage, the Ground Force had hoped to be able to transport it by air. However, even for the lighter Locust, transport by C-54 required dismantling the turret. The appearance of the C-82 with its 10 t payload made it possible to consider transporting the M24 in two parts, but this method was far too expensive in time, labor and material. In addition, aircraft then under development would be able to carry vehicles the size of the Chaffee without prior disassembly.
After the end of hostilities, the Chaffee was used by many armies and saw fire in Korea and Indochina. This tank, at the height of the most diverse missions, also served as a starting point for a very diversified experimentation. This is how we tried the exchange of turrets with the French IAMX-13; moreover, at the Aberdeen test site, an M24 received the suspension of a 12 t German tractor, three-quarters tracked, but the off-road performance of this prototype was very disappointing. A 76 mm self-loading gun was mounted on a mock-up of the M24, but the project went no further. The T31 'anti-personnel' tank lined mines on either side of its hull to repel enemy infantry 'close combat' attacks and its experimental cupola mounted two .50 machine guns to increase the firepower available to the commander. tank. Many Chaffees remain in service around the world, including with the Israeli, Pakistani and Uruguayan armies. The Norwegian army transformed the M24 into a tank destroyer by giving it a French 90 mm high or low pressure; it designates this vehicle NM116