The U.S. Army’s M42 Duster grew from the wartime M19 Multiple Gun Motor Carriage, a self-propelled anti-aircraft gun introduced in 1944 with twin 40mm Bofors rifles. After the war, the Army replaced the M19’s M24 Chaffee chassis with the M41 Walker Bulldog chassis while keeping the 40mm turret, creating the M42 Duster in 1952. The change improved reliability and simplified supply lines, and 3,700 were built at GM’s Cleveland Tank Plant. Because production began in 1952, it missed the Korea War and instead served with armored divisions. In the late 1950s, the Army concluded that supersonic aircraft flew too fast and too high for the Duster, so it began replacing it with the self-propelled HAWK surface-to-air missile system and transferring M42s to the National Guard by 1963, although the 517th Air Defense Regiment kept some in the Panama Canal Zone into the 1970s. In Vietnam, poor low-altitude performance by HAWK missiles led the Army to recall the M42 to protect U.S. troops on the ground. Although it achieved a few early kills, North Vietnamese air attack never became a major threat, and the vehicle more often supported troops with direct fire. The North Vietnamese called it “The Fire Dragon” because of its heavy tracer and high-explosive fire. Mechanical problems, including drivetrain breakdowns and overheating engines that could catch fire, eventually led to its withdrawal from Vietnam. The rest of its service life was spent with the National Guard, and although the last M42s in U.S. service were retired in 1988, some nations still use them in small numbers today.