Armidale Class Patrol Boat Sustainment

Armidale Class Patrol Boat, HMAS Maitland (foreground) in formation during Exercise Kakadu.

The Royal Australian Navy (RAN) operates 14 Armidale Class Patrol Boats (ACPBs).

The Armidale Class Patrol Boats (ACPBs) provide the RAN with an improved capability to intercept and apprehend vessels in a greater range of sea conditions than the earlier patrol boat classes, the Fremantle Class and the Attack Class.

The ACPBs are built by Austal Ships. They are constructed from marine grade aluminium alloys with a nominal design service life of 15 years. Aluminium alloys are particularly susceptible to fatigue cracking, thus it is very important to carry out life-of-type evaluation.

DST Group has developed a structural (finite element) model of an ACPB and analysed using finite element analysis tool MAESTRO. This involved becoming familiar with the hull, understanding the classification rules, and understanding the load cases of the ACPBs. 

The short-term aim of the model is to ascertain the boat's global structural response to it's loading condition and for DST to obtain a stronger capability in structural integrity measurement. 

DST has installed an onboard hull monitoring system on one of the Armidale Class Patrol Boats to measure ship motions, sea loads and the associated ship responses. The hull monitoring data provide validation to numerical prediction tools as well as provide direct operational advice.

These enable DST to provide advice to the RAN on the operational limitations of the vessels, improved management of the hull through inspections, maintenance and repair by identifying stress critical area, fatigue life estimate and corrosion.

Key information