The colonial service Acheron-class torpedo boats were built by the Atlas Engineering Company at Sydney in 1879 for the New South Wales naval service. They were originally armed with a single spar torpedo, but this was replaced in 1887 with two 14-inch torpedoes. They were sold in 1902.

Design

The boats were designed 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:...

 to mount a single spar torpedo

Spar torpedo

A spar torpedo is a weapon consisting of a bomb placed at the end of a long pole, or spar, and attached to a boat. The weapon is used by running the end of the spar into the enemy ship. Spar torpedoes were often equipped with a barbed spear at the end, so it would stick to wooden hulls...

. They displaced a mere 16 tons and were 78 in 0 in (23.77 m) in length.

Construction

In 1877 the Government of the colony of New South Wales ordered the construction of two "outrigger" torpedo boats, in response to concerns about a possible threat from foreign warships. Tenders closed on 17 January 1878 and the winning contractor was the firm of Atlas Engineering Company at Sydney. Both vessels were launched in early 1879 and Acheron started her trials in Sydney Harbour on 1 March 1879.

Service

Neither of the boats ever left the confines of Sydney Harbour, and they were never used in anger. By 1885 they were in a state of disrepair and were docked at Cockatoo Island

Cockatoo Island

Cockatoo Island may refer to the following places in Australia:*Cockatoo Island, New South Wales in Sydney Harbour, New South Wales...

. In the late 1880s they were described as "Sydney’s third line of defence", after the naval artillery and the defensive mines. Both boats were refitted again in 1896.

Fates

On 1 March 1901 Acheron and Avernus became part of the Commonwealth Naval Forces. By this time they had become thoroughly outmoded and the Federal Government ordered their sale. In December 1902 Acheron was sold for £425 and Avernus for £502.

Acheron became Sydney’s quarantine boat, renamed Jenner, and was paid off in the late 1930s. In the mid-1990s a workboat of the Royal Australian Navy detected a long thin hull with her side-scan sonar, which was thought to be the remains of Acheron. On the other hand, after sale Avernus was abandoned on the shores of Rushcutters Bay

Rushcutters Bay, New South Wales

Rushcutters Bay is a harbourside eastern suburb of Sydney, in the state of New South Wales, Australia. Rushcutters Bay is located 3 kilometres east of the Sydney central business district, in the local government area of the City of Sydney....

 and in the 1940s was sunk for reclamation of land at Glebe

Glebe, New South Wales

Glebe is an inner-city suburb of Sydney. Glebe is located 3 km south-west of the Sydney central business district and is part of the local government area of the City of Sydney, in the Inner West region....

.

Ships

Name	Ship Builder	Launched	Fate
Acheron	Atlas Engineering Company	1879	Sold on 12 November 1902, transferred to NSW quarantine service, renamed Jenner. Paid off in the late 1930s
Avernus	Atlas Engineering Company	1879	Sold on 12 November 1902. Abandoned on the shores of Rushcutters Bay and sunk for reclamation of land at Glebe in the 1940s