HMVS Nepean was a second-class torpedo boat

Torpedo boat

A torpedo boat is a relatively small and fast naval vessel designed to carry torpedoes into battle. The first designs rammed enemy ships with explosive spar torpedoes, and later designs launched self-propelled Whitehead torpedoes. They were created to counter battleships and other large, slow and...

 constructed for the Victorian Naval Forces and later operated by the Commonwealth Naval Forces and the Royal Australian Navy

Royal Australian Navy

The Royal Australian Navy is the naval branch of the Australian Defence Force. Following the Federation of Australia in 1901, the ships and resources of the separate colonial navies were integrated into a national force: the Commonwealth Naval Forces...

. She was sunk on mud flats on Swan Island in Port Phillip Bay in 1912 after being stripped of equipment and machinery.

Design and construction

Nepean was one of several torpedo boats ordered by the government of Victoria

Victoria (Australia)

Victoria is the second most populous state in Australia. Geographically the smallest mainland state, Victoria is bordered by New South Wales, South Australia, and Tasmania on Boundary Islet to the north, west and south respectively....

 in 1882 to protect the colony from a possible Russian or French attack, and was built by John I. Thornycroft & Company

John I. Thornycroft & Company

John I. Thornycroft & Company Limited, usually known simply as Thornycroft was a British shipbuilding firm started by John Isaac Thornycroft in the 19th century.-History:...

, Chiswick

Chiswick

Chiswick is a large suburb of west London, England and part of the London Borough of Hounslow. It is located on a meander of the River Thames, west of Charing Cross and is one of 35 major centres identified in the London Plan. It was historically an ancient parish in the county of Middlesex, with...

.

Nepean was 67 feet (20.4 m) long, with a draught of 3.25 foot (0.9906 m), and a displacement of 12.5 tons. She was designed with a low freeboard

Freeboard

Freeboard may refer to:* Freeboard , the height of a ship's deck above the water level.* Freeboard , a six-wheeled skateboard designed to act like a snowboard....

, to minimise her profile. The boat had a maximum speed of 17 knots (9.3 m/s), which she would use to close rapidly with enemy vessels before attacking.

Fate

She was sunk on mud flats on Swan Island in Port Phillip Bay in 1912 after being stripped of equipment and machinery.