US Assault Support Patrol Boat

The Assault Support Patrol Boat (ASPB) (also known as the Alpha Boat), was a heavily armed and armored riverine patrol boat developed by the US Navy for use in the Mekong Delta, during the Vietnam War.

The first ASPBs arrived at Vung Tau, Vietnam 20 September 1967 and  were to act as escorts and provide protection for the slower Armored Troop Carriers (ATCs) of the Mobile Riverine Force during the troop transport phase of riverine assaults.

Due to their steel construction and armor, and  a top speed of 14.8 knots they performed escort, rapid response, and minesweeping duties. While the armament and embarked troop complement gave the boats a sizeable punch during hostile engagements.