M42 Duster

Infobox Weapon
name=M42 Duster


caption=M42 in Yad la-Shiryon museum, Israel.
origin=United States
type=Self-propelled anti-aircraft gun
is_vehicle=yes
length=5.82 m
width=3.23 m
height=2.85 m
weight=24.8 t (loaded)
speed=72 km/h
vehicle_range=160 km
suspension=torsion bar
engine=6-cylinder air cooled gasoline
engine_power=500 hp (375 kW)
pw_ratio=22.2 hp/tonne
crew=4–6
primary_armament=M2A1 40 mm twin anti-aircraft gun
secondary_armament=1 x M1919A4 7.62 mm machine gun
armour=9–25 mm

The M42 40 mm Self-Propelled Anti-Aircraft Gun, or "Duster" as it is known, is an armored light air-defense gun built for the U.S. Army from 1952 until December 1959. Production of this vehicle was performed by the tank division of the General Motors Corporation. It used components from the M41 light tank and was constructed of all welded steel. The 500 hp, six cylinder, air-cooled, gasoline engine is located in the rear of the vehicle. A total of 3,700 M42s were built. The vehicle has a crew of six and weighs 22,500 kg (49,500 lb) fully loaded. Maximum speed is 45 mph with a range of 100 miles. Armament consists of fully automatic twin 40 mm M2A1 Bofors, with a rate of fire of 240 rounds per minute (rpm) and either a .30 cal. Browning M1919A4 or M-60 Machine Gun.

Although the M42 Duster was initially designed in the anti-aircraft role, it found great success when used in the Vietnam War against unarmored ground forces.

Development

During the course of the Korean War, the U.S. Army decided to phase out all vehicles based on the M24 Chaffee chassis, such as the M19 Gun Motor Carriage 40mm Anti-Aircraft, in favor of designs that utilized the chassis of the M41. Since the 40mm guns were still seen as an effective anti-aircraft weapon, the turret of the M19 was simply mounted to the M41 chassis with few changes except a partial redesign to accommodate the larger turret ring of the M41 and designated as the M42. Initially, aiming the 40mm guns assisted by a radar fire control system housed in a secondary vehicle of similar design but this idea was scrapped as development costs mounted.

ervice history

Production of the M42 began in early 1952 at GM's Cleveland Tank Plant. It entered service in 1953 and replaced a variety of different anti-aircraft systems in armored divisions. In 1956, the M42 received a new engine and other upgrades along with other M41 based vehicles, becoming the M42A1. Production was halted in Dec. 1959 with 3700 examples made during its production run. Sometime in the late 50s, the U.S. Army reached the conclusion that anti-aircraft guns were no longer viable in the jet age and began field a self propelled version of the HAWK SAM instead. Accordingly, the M42 was retired from front line service and passed to the National Guard with the last M42s leaving the regular Army by 1963.

Vietnam War

Unfortunately, the HAWK missile system performed poorly in low altitude defense. To ensure some low altitude anti-aircraft capability for the ever increasing amount of forces fielded in Vietnam, the Army began recalling M42A1s back into active service and organizing them into air defense artillery (ADA) battalions. Three M42A1 equipped ADA battalions were sent to Vietnam, the first arriving in late 1966.

Despite a few air kills early, the air threat posed by North Vietnam never materialized, and ADA crews found themselves increasingly involved in ground support missions. Most often the M42 was on point security, convoy escort or perimeter defense. The "Duster" (as it was called by U.S. troops in Vietnam) was soon found to excel in ground support. The rapid firing 40mm guns could devastate massed infantry attacks or sweep away guerrillas hiding in the jungle with equal ease.

Post Vietnam

The last M42A1 equipped ADA units left Vietnam in 1972 and the Duster was returned to the National Guard. The U.S. Army maintained multiple National Guard M42 battalions as a corps level ADA asset until the system was retired in 1988.

Variants

*M42
*M42A1: received the AOSI-895-5 engine (500 hp).
*Type 64: Taiwanese light tank variant produced by mating turrets of M18 tank destroyer onto M42 hulls.

External links

* [http://afvdb.50megs.com/usa/m42duster.html AFV Database]
* [http://www.mystae.com/reflections/vietnam/duster.html ADA Units in Vietnam]
* [http://svsm.org/gallery/M42 Photo gallery at svsm.org]