HMAS Protector (ASR 241)

HMAS Protector (ASR 241) was a Royal Australian Navy (RAN) trials and submarine rescue ship. Built in 1984, the ship was initially operated by the National Safety Council of Australia as MV Blue Nabilla. She was purchased by the RAN in 1990 for use as a surveillance, training, and diving support vessel. During her military career, Protector supported the trials of the Collins-class submarines, and was involved in a search for the shipwreck of the World War II cruiser HMAS Sydney (D48). The ship was decommissioned and sold to Defence Maritime Services in 1998. Renamed Seahorse Horizon, the ship operates out of HMAS Creswell as a training vessel.

Construction
The ship was constructed by Stirling Marine Services in Western Australia, and was completed in 1984.

Operational history
She operated as MV Blue Nabilla for the National Safety Council of Australia until 1990.

The ship was purchased by the RAN on 18 October 1990, fitted with a LIPS dynamic positioning system, two Remotely Operated Vehicles and a recompression chamber. She was commissioned as HMAS Protector in November 1990. She supported the Collins-class submarine trials and acceptance process from 1992. On 10 June 1995, Protector was slightly damaged when a switchboard malfunction aboard HMAS Collins (SSG 73) caused the submarine to ram the trials ship. The vessel also performed in the surveillance, training, and diving support roles.

During 1997, Protector undertook a brief and unsuccessful search for the remains of the World War II cruiser HMAS Sydney (D48).

When Protector was decommissioned in 1998, she was sold to the RAN's support craft contractor, Defence Maritime Services, and remains in use as a training ship operating out of HMAS Creswell under the name Seahorse Horizon. In 2002, Seahorse Horizon took part in Exercise Dugong, laying and recovering mines.