Type of river boat

Swift Boat, US Navy; official designation: PCF-Patrol Craft Fast. 50' long, all aluminum construction, complement of 5 crewmen and commanded by one officer, usually a LTjg (Lieutenant Junior Grade).

Equipped with two diesel engines and three .50 machine guns; twin fifties in the turret, and one over and under aft. The aft .50 was mounted atop the mounted 81mm mortar (lanyard fired).

The Swifts operated within the US Navy's Brown Water Navy during the Vietnam War.