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M50 Ontos (Thing)

1955 COLD WAR VIETNAM WAR

History

One of the most unique tanks of the Vietnam War period (1955-1975) was the M50 "Ontos". Its name means "thing" in Greek, and this little machine is aptly named, unlike any chariot I've seen before. The vehicle consists of three people in a compact sloping fuselage configuration with an overhead 6 x 106mm recoilless gun. The type was considered an air transport tank destroyer, but was better used in an anti-infantry role during the Vietnam conflict. The U.S.

Marine Corps became its primary user, and Allis Chalmers built 297 units from 1955 to 1957.

The M50 was originally born out of five T156 pilot vehicles, each armed with a recoilless rifle of a different caliber for testing purposes. Additional trials followed with 24 vehicles with standardized 106mm guns. The program then ended production of the pilot T156E2 model, which became the production-quality M50. The U.S.

Marine Corps first fielded their Ontos vehicles in October 1956.

Engineers tried to make the tank as compact as possible while maintaining the survivability of the crew. This involves the use of heavily sloping sides where the armor can be thinner but still provide the required ballistic protection. However, this reduced the interior space of the cabin, making conditions quite cramped for the three crew members.

Armor is only good for small arms fire and possibly artillery spray and stuff. The driver is seated on the front left with the engine on his right.

The weapon of choice for the M50 became the M40 recoilless rifle. This weapon appeared in the mid-1950s and was used extensively during the Vietnam War and beyond. It fires several types of 106x607mmR projectiles, including HEAT and HEAP ("High Explosive, Anti-Tank" and "High Explosive, Armor Piercing" respectively). It's designed so that recoil can be reduced by subtly venting the propellant gases during ignition. This creates a forward motion to counteract the gun's backward force - reducing recoil.

Therefore, no complicated recoil mechanism is required, and the structure of the weapon can be kept light. Designed for anti-tank purposes, the M40 was initially deployed as a land-based, crewed operating system with a maximum range of 6,850 meters.

HE and other anti-personnel munitions extend their tactical capabilities beyond pure tank warfare.

For the M50, six 106mm guns were mounted in groups of three on low turrets on either side of the upper hull. The top two rifle units are mounted side by side, the third is mounted lower. Combined with some rifles is the Remington M8C .50 caliber scout rifle for recoilless weapon training.

The machine guns are mounted on the two outermost guns (numbered "2" and "5" when collected from left to right counted from the rear of the vehicle) and the two innermost guns. These rifles are awarded with 80 rounds of .50 caliber ammunition. Towers have limited side and height values.

Use the scout rifle after the gunner's optical aiming. Combined, this provides a level of accuracy when the rifle is fired. Self-defense is provided by a .30 caliber Browning M1919A4 air-cooled machine gun.

The high position of the guns allowed the M50 crew to hide behind solid or earth walls for protection and still fire overhead. In addition, recoilless rifles retain their crew duty capabilities and can be quickly disengaged from the vehicle and operated as usual - ideal for arranging ambushes or otherwise supporting infantry.

18 x 106mm shells were brought on board for reloading.

The small car was originally equipped with a 6-cylinder General Motors SL12340 series petrol engine with an output of 127 hp at 1,800 rpm. The power unit is in a right forward fuselage arrangement that allows a split door arrangement to be surface mounted on the rear of the fuselage to allow the crew to enter and exit the vehicle.

Despite only 47 gallons stored in the internal fuel tank, road speeds hit 30 mph and a range of 150 miles. The engine works with an Allison XT-90-2 drivetrain and drives the vehicle via a front drive sprocket.

The three wheels are also in play, as are the low-to-the-ground chain idlers at the end of the chain system.

The M50A1 variant carries the original M50 production branding and introduces the Chrysler HT-361-318 V-8 gasoline engine, now mated to an Allison XT-90-5 transmission. Other distinguishing details include the addition of air intakes above the hull engine for air intake purposes. Access panels have been added to the gearbox for easier maintenance. The new engine increases power output to 180 horsepower.

The designation came as the new M50 standard, although only 176 of the original stock from 1963 to 1965 were converted to this.

Despite its design as a tank destroyer, the Ontos functions better as an anti-personnel weapon, firing high-explosive rounds at long distances. The North Vietnamese Army did not have a large field of tanks, so the M50 was of limited use as a dedicated tank destroyer, but it transcended its service life as a fire support system.

As a result, it didn't take long for an anti-infantry approach to be adopted.

In practice, the Ontos has proven that it can be a dangerous weapon in certain battlefield conditions, although it has several major drawbacks in combat vehicle operation. The hull has little armor except in confined areas, and its sloping nature only proves effective to a certain extent, with little protection from hidden mines or rockets.

In addition, the recoilless rifle had to be reloaded by a crew member from outside the vehicle, making him an unnecessary danger to both the environment and the battlefield. The internal fuel tank severely limits range, especially off-road on rough terrain.

Despite these limitations, users do seem to enjoy their little "stuff". The vehicle's compact size makes it truly portable through several measures including helicopters and rail vehicles. They can traverse softer terrain and narrow streets where heavier tanks cannot. It also has excellent maneuverability due to its small size and light stature, and is relatively low profile for a combat vehicle - difficult to train at enemy distance.

In a fire support role, the impressive six rifles became a godsend against enemy infantry cover, so much so that the NVA and Viet Cong troops feared and respected the small American machine.

Like all military vehicles, the Ontos ended its fleet in 1969 when the active fleet was retired. Beginning in 1970, M50s were shipped back to the United States and scrapped, while some lived longer as museum exhibits.