The M18 had a gasoline powered, 400 hp, Continental R-975 engine and it was capable of speeds of up to 88.5 km/h. It also had a crew of five men and it had a 3 speed forward, 1 speed reverse transmission. The M18 had torsion bar suspension system with five wheels on each side of the tank destroyer.
The armament consisted of an M1A1 76.2 mm main gun and a 12.7 mm Browning M2HB on top of the turret. The M18 also had a weight of 18,143.6 kg and a length of 6.35 meters. It could carry 624.5 liters, 45 rounds for the main gun, 800 rounds for the 12.7 mm machine gun, and it had a maximum range of 168.9 km. The armor was 12.7 mm in most areas of the tank including the sides and the frontal armor plate. It was a 6 mm thick in the underside of the vehicle and it was 7.9 mm at the top. Overall, the armor was hardly enough to deflect most enemy tank shells, meaning that speed was the Hellcat's largest advantage.
The T41 Armored Utility Carrier along with the M39 Armored Utility Carrier were turret-less M18s that were modified for transport purposes. The M39 could carry eight armed soldiers and it was defended by an Browning M2HB. The T41 was also used for carrying troops and supplies, but it was especially used for carrying artillery. The T41E1 was actually the M39 right before it had its name changed. Another variant of the M18 Hellcat was the T65 Flame Tank which as the name suggest was an M18 turned into a flame tank. It had the turret removed and had a modified hull so the flamethrower could be added. There were also many other variants that were proposed and rejected such as the T87 Amphibious Gun Motor Carriage.
One developmental variant existed. Ith mated the turret of an M36 Jackson and it's respective 90 mm M3 gun on the M18's chassis, in an attempt to improve the firepower. With the new turret brought massive weight and recoil issues, and despite this the "Super Hellcat" (as it was known post-war) was order by Army Ground Forces. The project was cancelled at the end of the war, and the order was cut.
The M18 Hellcat's first prototype was the T49 GMC (Gun Motor Carriage) and it featured a 57mm main gun. The next prototype was the T67 GMC and it featured a 75 mm main gun. The last and final prototype was the T70 GMC and it featured a 76.2 mm main gun. It was first accepted in 1943 and it appeared on the battlefield in 1944. The M18 Hellcat was produced by Buick and it was meant to be a more armored tank destroyer rather than the M10 Tank Destroyer or the M36 Tank Destroyer which was produced to late in the war.
Although the M18 was meant to have more armor than the M10 or the M36, it was still lightly armored considering it only had half an inch of armor. This is why it was susceptible to German Tiger or Panther tanks. M18s were used in the European Theater mainly by American tank crews, but they were not used in the Pacific Theater. By the end of the war, some 2,000 M18s had been produced and even after World War II M18s were being used by countries such as Yugoslavia.
- ↑ http://www.wwiivehicles.com/usa/tank-destroyers/m18.asp
- ↑ http://www.militaryfactory.com/armor/detail.asp?armor_id=250