M56 Scorpion

1953 COLD WAR SELF-PROPELLED ARTILLERY VIETNAM WAR

• 1 History of the M56 Scorpion
• 2 M56 Scorpion Specification
  • 2.1 Basic
  • 2.2 Roles
  • 2.3 Dimensions
  • 2.4 Performance
  • 2.5 Performance
  • 2.6 Armor
  • 2.7 Changes

History of the M56 Scorpion

The M56 "Scorpion" SPAT ("Self-Propelled Anti-Tank") vehicle is an air-transportable all-track self-propelled anti-tank system equipped with a 90mm gun. The vehicle was specifically designed to provide U.S. paratroopers with a viable artillery component for their rather light weapons.

Paratroopers proved to be the norm during World War II, when all major parties used their speed and surprise to take key enemy positions ahead of the main force. Development of the M56 ensued during the Korean War (1950-1953), and from 1953 to 1959 the car appeared in 325 units from the General Motors Cadillac factory in Cleveland.

For the next decade, the M56 continued to serve in airborne battalions and infantry tank companies, demonstrating its compactness by air deployment/transportation by fixed-wing aircraft or precision landing by transport helicopters.

Based on the T101 pilot vehicle, the M56 fuselage structure is entirely welded and riveted aluminum. Its 90mm M54 anti-tank vehicle is closely related to the main gun armament of the M47 "Patton" (MBT) main battle tank. The vehicle is allowed to carry 29 x 90 mm projectiles. It was designed for a standard four-person combat crew, including driver, commander, loader, and gunner, and was powered by a 200-horsepower Continental A0I-402-5 gasoline engine.

This works with an Allison CD-150-4 drivetrain with two forward gears and one reverse. The suspension consists of torsion tubes placed on wheels 1 and 4 (4 wheels in total on one side of the fuselage), while a torsion bar system is installed on wheels 2 and 3. Speed ??on the road is around 28 mph, and range is limited to 140 miles. Vehicle operating weights range from 14,000 lbs to 16,000 lbs.

Unlike other armored fighting vehicles of the time, the M56 adopted a pneumatic tire arrangement, further reducing its combat weight.

An obvious shortcoming of the M56 design was that the crew was completely exposed to the harsh environment and severely exposed to the dangers of the battlefield, the only protection being the front fragmentation shield installed as part of the gun mount. The lack of a proper airframe layout allowed engineers to keep the M56 in a lightweight, portable design. The loader stood on a folding platform while reloading the weapon through the breech. The main gun has manual aileron and elevation functions for precise ranging.

On the left is the driver's seat with the associated control lever. Part of the gun shield was cut out of the windshield to allow the driver to operate behind some protection. The radio and the section chief sat to the right of the driver. This leaves room along the right side of the breech for the gunner and ammunition handler. Ammunition types range from the usual high-explosive (HE) types to the more advanced armor-piercing (AP) types.

The ammunition depot is located under the artillery floor and is accessible from a platform at the rear of the vehicle.

Despite the complete lack of aircrew protection, the system proved to be a formidable mobile artillery piece, especially for these lightly armed paratroopers. The car served with the legendary 82nd and 101st Airborne Divisions, and during the Vietnam War (1955-1975).

Designed with speed and surprise in mind, paratroopers carry all the tools they need for a lethal craft to jump from an aircraft ready for action into the battle below. The M56 gives these units a chance against armor while on the ground.

The M56s fought in Vietnam from 1957 to 1970, when they were withdrawn during the American retreat to Southeast Asia.

Aside from the open crew compartment, the M56 is not without its shortcomings. Its main gun has a maximum allowable range of 1,500 meters, and the recoil of the tank gun proves that the light chassis is not strong.

During firing, the front of the vehicle would bounce violently, pushing the rear to the ground. Not only did this hurt the occupants and chassis, it also improved the vehicle's positioning, raising smoke and dust and giving up previously hidden positions.

The M56 was eventually replaced by the M551 Sheridan air-dropped light reconnaissance tank with a more powerful 152mm main gun in a more suitable turret and hull configuration. Even with the arrival of the M551, the M56 Scorpion had limited service until the end of the Vietnam War, although it was later relegated to fire support rather than direct contact with enemy armor.

The M56 base chassis was also used in several other tracked US Army developments of the period, including the M50 "Ontos" recoilless rifle delivery vehicle.

After the official retirement of the M56 Scorpion vehicles and M551 Sheridan tanks, the US Airborne Division has essentially no self-propelled components in its inventory, a status that remains unchanged to this day (2014). All remaining M56 parts are either scrapped or enjoyed as museum props.

The M56 is also exported to Morocco, Spain and South Korea.

M56 Scorpion Specification

Basic

Roles

Dimensions

Performance

Performance

Armor

29x90mm bullet

Changes