The Armidale class' is a class of patrol boats built for the Royal Australian Navy (RAN). Planning for a class of twelve vessels to replace the fifteen Fremantle class patrol boats began in 1993 as a joint project with the Royal Malaysian Navy, but was cancelled when Malaysia pulled out of the process. The project was reopened in 1999 under the designation SEA 1444, with the RAN as the sole participant. Of the seven proposals tendered, the Austal Ships/Defence Maritime Services proposal based on an enlarged was selected. The first vessel, , commissioned into the RAN in June 2005. Two more patrol boats were ordered in 2005, bringing the class to fourteen.
The Armidales are longer and heavier than their Fremantle class predecessors, with improved seakeeping ability and increased range, allowing them to reach Australia's offshore territories. The ships are multi-crewed, with three ship's companies available for every two vessels; this allows the patrol boats to spend more time at sea without cutting into sailors rest or training time. However, during their early service life, there were problems with the fuel systems across the class, and a 20-bunk auxiliary accommodation compartment has been banned from use after toxic fumes were found in the compartment on at least two occasions.