The Auto, also known as Machine Gun, is a recurring weapon in the 1940 series. It is usually represented by a rotating gun barrel icon.
The Auto is a simple, fast-firing weapon. In 1943: The Battle of Midway, it would fire for as long as the fire button was pressed, a mechanic which was ditched in later games with the introduction of charged attacks. It returns in 1941: Counter Attack, where it is renamed to Machine Gun, again as a fast-firing weapon. When charged, it fires a series of homing missiles. It's last appearance is in 1942: Joint Strike, where it is a temporary weapon only found in a few portions of the stages.