M163 VADS

M163 VADS. The M163 Vulcan Air Defense System (VADS) was an American self-propelled anti-aircraft gun developed during the Cold War. Mounting a six-barreled Gatling-style cannon on a modified M113 armored personnel carrier chassis, it was designed to provide forward combat units with mobile, short-range protection against low-flying aircraft. The system entered service with the United States Army in 1969, serving as a key component of divisional air defense before being gradually replaced by the M6 Linebacker and the MIM-72 Chaparral missile system.

Development and design

The development of the M163 was initiated in the mid-1960s to fulfill a requirement for a mobile, radar-directed anti-aircraft gun to defend Armored cavalry and Mechanized infantry units. The project was led by the General Dynamics corporation, which integrated the existing 20 mm M168 cannon, a derivative of the M61 Vulcan used on aircraft like the F-104 Starfighter, onto the ubiquitous M113 armored personnel carrier. The fire control system centered on the AN/VPS-2 range-only radar mounted atop the gun, which provided automatic lead-computing for the gunner. This design emphasized rapid engagement of fleeting targets, with the cannon capable of firing standard M50 series ammunition at a high cyclic rate. The entire system, including the four-man crew, was housed within an open-topped, lightly armored turret, offering limited protection against shell splinters and small arms fire.

Operational history

The M163 first saw combat during the later stages of the Vietnam War, where it was deployed to protect firebases and convoys from attacks by low-flying aircraft like the Mikoyan-Gurevich MiG-17 and helicopters. Its most significant foreign combat use was by Israel during the Yom Kippur War, where it was employed against Egyptian Air Force and Syrian Air Force aircraft with mixed results, often used in a ground support role. The system also saw extensive action during the Lebanese Civil War with various factions. In U.S. service, it remained a frontline system through the 1980s, with units deployed during operations like Operation Urgent Fury in Grenada. Its final major conflict was the Gulf War in 1991, where it provided point defense for units like the 3rd Infantry Division before being rapidly phased out of the United States Army inventory in favor of missile-based systems.

Variants

The primary variant was the baseline M163, which entered full-scale production in 1968. An upgraded model, the M163A1, featured an improved AN/VPS-2 radar system for better reliability and accuracy. A proposed product-improved version, sometimes referred to as the M163A2, was tested with a new digital fire control computer but was not adopted. Several experimental upgrades were evaluated, including integration with the MIM-72 Chaparral missile launcher, which later evolved into the separate M6 Linebacker system. No major derivative vehicles were produced, though the chassis and basic concept influenced later projects like the M247 Sergeant York.

Operators

The primary operator was the United States Army, which fielded the system with units in West Germany, South Korea, and the continental United States. It was widely exported under the Military Assistance Program to allied nations including Israel, Egypt, Jordan, Morocco, Saudi Arabia, Taiwan, Thailand, Tunisia, and the Philippines. Several of these operators, such as Israel, subsequently retired their systems, while others like Taiwan and Morocco maintained them in reserve or secondary roles into the 21st century. Captured examples were used by various militias during conflicts in Lebanon and possibly Afghanistan.

Specifications (M163)

The M163 was based on the M113 armored personnel carrier chassis, powered by a Detroit Diesel 6V53T engine coupled to an Allison XTG-411-2A automatic transmission. Its main armament was the 20 mm M168 cannon, a variant of the M61 Vulcan, with a maximum rate of fire of 3,000 rounds per minute and a practical rate of 1,000–1,500 rpm. It carried 2,100 rounds of 20 mm caliber ammunition in three ready boxes. The AN/VPS-2 radar had an effective range of approximately 5,000 meters against aircraft-sized targets. The vehicle had a combat weight of 12.3 metric tons, a top road speed of 68 km/h, and an operational range of 480 kilometers. The aluminum armor provided protection against small arms fire up to 12.7 mm caliber.

Category:Self-propelled anti-aircraft weapons of the United States Category:Cold War self-propelled anti-aircraft guns Category:M113 armored personnel carrier variants Category:General Dynamics