First Australian frigate to complete AMCAP upgrade tests stability

The first Royal Australian Navy Anzac-class frigate to undergo the Anzac Midlife Capability Assurance Program (AMCAP) upgrade has completed the inclining experiment at Henderson Shipyard, Western Australia to test stability.

HMAS Arunta underwent the test after more than a year out of the water as part of the upgrade.

An inclining experiment is a test performed on a ship to determine its stability, lightship weight and the coordinates of its center of gravity. The experiment is applied to newly constructed ships greater than 24m in length, and to ships altered in ways that could affect stability.

The weight of a ship can be readily determined by reading draughts and comparing with the known hydrostatic properties. The ‘metacentric height’ (GM), which dominates stability, can be estimated from the design, but an accurate value must be determined by an inclining experiment.

The experiment involves positioning the ship in a still body of water and applying weights in varying configurations throughout the ship and measuring the list of the ship for each configuration.

The experiment that was performed on HMAS Arunta will be used as a basis for updating the trim and stability handbook for all future AMCAP ships.

The upgrade, being implemented by the Warship Asset Management Agreement (WAMA), includes significant improvements to major platform systems such as the communications center, and the replacement of the ship’s long range air search radar.

As explained, the replacement mast is taller and wider than the existing mast so that it can accommodate the new CEA L-Band radar system, while retaining the existing anti-ship missile defense radar capability. The new L-Band radar capability will be integrated into the existing combat management systems of the ships by SAAB Australia.

Arunta’s Marine Engineer Officer, Lieutenant Commander Leonard Woodman, said the inclining experiment is another important milestone for both Arunta and the Anzac Mid-Life Capability Assurance Program (AMCAP).

“The inclining experiment, while being a standard practice after a significant upgrade, has provided good data that will support all the ships that come after us on the AMCAP,” he said.

The AMCAP aims to remediate obsolescence issues and upgrades ship systems, positioning the Anzac Class ships for sustainment and maintenance of its warfare systems capabilities.

WAMA is an alliance consisting of the Commonwealth, BAE Systems Australia, Saab Australia and Naval Ship Management Australia.

Arunta is the first ship to complete the AMCAP upgrade and is scheduled to return to the fleet this year. HMAS Anzac, Arunta’s sister ship has already started upgrade work at the Henderson facility.