The White Ensign has come down for the last time on two of the RAN's warships, HMAS Rushcutter and HMAS Shoalwater.

The pair of 170 tonne inshore minehunters was decommissioned in a ceremony at their home base, HMAS Waterhen, on August 14.

The pair had been in reserve for some months.

A crowd of former members of their Ship's Companies, family members and senior naval officers attended the ceremony.

Their decommissioning marked the end of an Australian designed class of ship which was unique in hull form, construction materials and operational characteristics.

They were catamarans.

Rushcutter the first MHI, was built at the Carrington Slipways in Newcastle and commissioned on November 1, 1986.

Shoalwater was commissioned on October 18, 1987.

While designed for mine hunting operations in sheltered waters the ships also fulfilled a vital training role by maintaining practical mine warfare skills in the RAN.

This allowed the Navy to retain a core level of expertise on which to develop with the introduction of the Mine Hunter Coastal ships, the Huons.

The ships usually carried a ship's company of 13.

They were fitted with Atlas hull mounted sonar as well as two remote control mine disposal vehicles.

Two .50 inch machine guns were also carried.