|
3-in Gun Motor Carriage M18 |
|
|
|
|
Whereas the MIO was produced for the tank destroyer battalions by converting an existing tank chassis (the M4A2), the Gun Motor Carriage M18 was designed from the outset for the tank destroyer role. Development began during 1942, and the first examples were ready during 1943. In service the M18 proved to be one of the best examples of the American tank destroyer concept. It was much smaller than the MIO and weighed only about half as much, but it carried a more powerful gun and was much faster, Indeed, the M18 was the fastest tracked vehicle to be used in action during World War II. The gun was the 76,2-mm (3-in) MIAI or M1A2, the latter having a muzzle brake. The MIAI gun was a development of the gun used in the MIO, but had a better allround performance and it was mounted in an open-topped turret. In appearance the M18 resembled a tank, and it did indeed have a 360° traverse turret, but its armour protection was much less than would be expected in a tank and the M18 relied upon its mobility and striking power to defend itself, The engine was positioned to the rear of the hull and was a radial air-cooled petrol engine with aviation origins that was powerful enough to give the M18 a good powerto- weight ratio to provide the vehicle with excellent acceleration and agility. Internal stowage was such that as well as carrying the crew of five men there was space for 45 76.2-mm rounds and a 12.7-mm (0.5-in) heavy machine-gun for local and anti-aircraft defence. In service with the tank destroyer battalions the M18 was given the name The M18 Hellcat had the distinction of being the fastest ofallAFVs used during World War II. Armed with a long 76-mm (3-in) gun, it was an ideal tank-hunting vehicle, but as with other vehicles of its type it generally lacked armour and was fitted with an open-topped turret. Hellcat. Despite their success in action the M 18s were gradually switched from the tank destroyer battalions as the enthusiasm for the exclusive tank destroyer concept dwindled, and by 1945 many M 18s were used by conventional armoured formations within the US Army. By then they were being used more and more as assault guns and conventional self-propelled artillery. The production run of the M18 lasted from July 1943 to October 1944, when it was obvious that the war was not going to last much longer. Between those dates 2,507 M18s were produced, some being completed without turrets as the M39 for use as high-speed troop or supply carriers. There was also a T65 Flame Tank based on the M18 with a much revised upper hull mounting a flame gun in front. The T88 Howitzer Motor Carriage was an attempt to mount a 105-mm (4.13-in) howitzer on the basic M18 and there were other attempts to mount a 90-mm (3.54-in) gun and turret on the chassis. None of these versions got past the experimental stage, a fate shared by many other trial versions of the basic M18 including a mobile command post, a utility carrier and an amphibious variant. Specification M18 Crew: 5 Weight: 17036 kg (37,557 lb) Powerplant: one Continental R-975 C1 radial petrol engine developing 253.5kW(340hp) Dimensions: length overall 6.65 m (21 ft 10 in) and hull 5.44 m (17 ft 10 in); width 2.87 m (9 ft 5 in); height 2.58 m (8 ft 5.5 in) Performance: maximum road speed 88,5 km/h (55 mph); road range 169 km (105 miles); gradient 60 per cent; vertical obstacle 0.91 m (36 in); trench 1.88 m (6 ft 2 in); fording 1.22 m (4 ft) Ml 8 Hellcats went out of production in October 1944 after 2,507 had been built. The Ml 8 was the only vehicle specifically designed for the US Army's tank destroyer role, and was a most successful combat vehicle capable of tackling all but the very heaviest German tanks.
|
