The M109, is an American 155 mm turreted self-propelled howitzer, first introduced in the early 1960s to replace the M44 and M52. It has been upgraded a number of times, most recently to the M109A7. The M109 family is the most common Western indirect-fire support weapon of maneuver brigades of armored and mechanized infantry divisions.
It has a crew of four: the section chief/commander, the driver, the gunner, and the ammunition handler/loader.
