Sergeant York Gun

M247 Sergeant York
A cutaway of the M247
Type	Self-propelled antiaircraft gun
Place of origin	United States
Production history
Designer	Ford Aerospace
Designed	1977–85
Produced	50
Specifications
Weight	54.4 ton
Length	7.67 m (25 ft 2 in) gun forward 6.42 m (21 ft 1 in) hull only
Width	3.63 m
Height	3.42
Crew	3
Shell	0.96 kg (projectile)
Caliber	40 mm (1.57in)
Elevation	-5° to +85°
Traverse	360°
Rate of fire	600 rpm
Maximum firing range	12.5 km
Main armament	2 × Bofors 40 mm L/70 (with 580 rounds)
Engine	Continental AVDS-1790-2D diesel 750 hp
Suspension	torsion bar
Operational range	500 km (310 mi)
Speed	48 km/h (road)

The M247 Sergeant York DIVAD (Division Air Defense) was a self-propelled anti-aircraft gun (SPAAG), developed by Ford Aerospace in the late 1970s. Based on the M48 Patton tank, it replaced the Patton's turret with a new one that featured twin radar-directed Bofors 40 mm rapid-fire guns. The vehicle was named after Sergeant Alvin York, a famous World War I hero.

The Sergeant York was intended to fight alongside the M1 Abrams and M2 Bradley in the U.S. Army, in a role similar to the Soviet ZSU-23-4 and German Flakpanzer Gepard. It would replace the M163 Vulcan Air Defense System and MIM-72 Chaparral, ad hoc systems of limited performance that had been introduced when the more advanced MIM-46 Mauler failed to mature.

Despite the use of many off the shelf technologies that were intended to allow rapid and low-cost development, a series of technical problems and massive cost overruns resulted in the cancellation of the project in 1985.

The first effective SPAAG in U.S. Army service was the all-manual M19 Multiple Gun Motor Carriage, which consisted of twin 40 mm Bofors guns based on the same chassis as used for the M24 Chaffee. When the M24 and vehicles on the same chassis were retired, the turrets were taken from the M19s, modified and mounted onto the M41 Walker Bulldog light tank chassis to produce the M42 Duster. While capable for the era it was designed in, by the time it reached widespread service in the late 1950s it was clear that it was ineffective against high-speed jet-powered targets. The Duster was completely removed from service by 1963, only to be re-introduced briefly during the Vietnam War when its replacement never arrived.