M163 VADS Vulcan Air Defense System
The M163 is a self propelled variant of the General Dynamics 20mm M61 rotary cannon mounted in most US aircraft since the '60s used for air defense. Long the standard mobile light anti-aircraft gun of the US Army, the Vulcan's only limitation was that it could not cannot be used for night time operation. From 1984 many M163 were upgraded under the M163 PIVADS Product Improved Vulcan Air Defence System program. Modification include new linked digital fire-control computer with range-only radar, and adding the new APDS round which increases range to 2,600m. The ill-fated M247 SGT. YORK DIVAD (Division Air Defence gun) was born of the U.S. ARMY'S need for a state-of-the-art mobile Anti-Aircraft gun system to replace the ageing M163 20mm Vulcan A/A gun and M48 Chaparral missile systems. With the Mi-24 Hind attack helicopters of the Soviet Army being fitted with the longer range AT-6 SPIRAL Anti-tank missiles and twin barrelled 23mm cannon, and with the newer Mi-28 Havoc nearing deployment, it was obvious by the early 1980s that the M163 and M48 systems would be totally out-classed in any future conflict. The U.S. Army Air Defense Artillery (ADA) branch has retired its M163 Vulcan tracked and towed 20mm Gatling gun systems, replacing them with Avenger HMMWVs with Stinger SAMs.
M163A2 PIVADS Product Improvement Vulcan Air Defense System
Specifications
Name M163 Crew 4 (Commander, gunner,loader, driver) Combat Weight 27,478 lb Hull length 16ft 2 in Width 8ftn9 3/4 inch Hight 8ft 8 3/4 inches Ground Clearance 16 inches Track Width 15 inh Main Armamet M168 gun system consisisting of 6 x 20mm barrels grouped on a geared motor, firing 3,000 rounds per min . Range antiair 5,249 ft, ground 3,281 yards Sensors and Fire Control visual tracking and M^1A1 lead-computing gunsight. AV.VPS-2 radar supplies range and range rate, AN/TVS-2B night vision sight Armor 5083 aluminum amor, 12-38mm) antimine amor on the bottom Powerplant Detroit Diesel model 6V-53 215 HP water cooled 2 stroke V-6 disel engine, Allison TX-Automatic transmission with 6 forward/ 1 reverse gear Spension Subension can be locked down during firing Speed road 35mph, cross country 19mph, 3.6 mph in water 300 miles range Obstacle Clearence vertical 2 ft , trench 5ft, 6in , amphibious 
