HMAS Platypus (I)
Submarine Depot Ship
John Brown and Co Ltd, Clydebank, Scotland
Laid Down
14 October 1914
28 October 1916
Launched by
Mrs Fisher, wife of the Australian High Commissioner to the United Kingdom
25 March 1919
13 May 1946
Dimensions & Displacement
Displacement 3476 tons
Length 325 feet
Beam 44 feet
Draught 15 feet 8 inches
Speed 15.5 knots
Machinery 2 sets of triple expansion reciprocating steam engines, twin screws
Guns 1 x 4.7-inch gun
Battle Honours DARWIN 1942-43
HMAS Platypus (I) Badge

HMAS Platypus was built to the order of the Australian Government. After completion in March 1917 she passed to the control of the Admiralty until 25 March 1919 when she was commissioned into the Royal Australian Navy at Portsmouth, under the command of Commander Edward Boyle VC RN, as a Submarine Depot Ship for six J Class submarines transferred as a gift from the Admiralty to the Royal Australian Navy.

Platypus sailed from Portsmouth on 8 April 1919 and with the submarines in company proceeded to Australia via the Suez Canal, arriving in Sydney on 15 July 1919.

HMAS Platypus in company with the J class submarines J1, J2, J4 and J5
HMAS Platypus in company with the J class submarines J1, J2, J4 and J5.

In February 1920 Platypus proceeded to Port Phillip where a Submarine Depot had been established at Geelong. In May 1922 the Naval Board decided to abandon the policy of maintaining a Royal Australian Navy Submarine Service. The three J Class boats remaining in commission were paid off, and on 1 July 1922 Platypus proceeded to Sydney. On 12 July at Sydney she paid off as a Submarine Depot Ship and on the following day recommissioned as a Destroyer Depot and Fleet Repair Ship. Operating with the Fleet, mainly in home waters, she served in this role until 1929.

Meanwhile, in 1924, a Five Year Naval Development Programme had been approved by the Australian Government, which included the re-establishment of a Royal Australian Navy Submarine Service with a flotilla of six boats.

Some of HMAS Platypus' crew members in October 1926
Some of HMAS Platypus' officers in October 1926.  The officer on the extreme right is a naval chaplain. 

Two Royal Navy Odin Class submarines were initially ordered. Named Otway (I) and Oxley (I), the submarines reached Sydney on 14 February 1929. Platypus returned to Sydney from a cruise in Queensland waters the following day. She paid off on 31 March 1929 to recommission in her former role as a Submarine Tender.

HMAS Platypus with the J Class Submarines
HMAS Platypus with the J Class Submarines.

The reconstituted Royal Australian Navy Submarine Service suffered from the outset from the world wide naval retrenchments beginning in 1929. On 10 May 1930 Otway (I) and Oxley (I) were paid off into Immediate Reserve with provision for one day diving exercises per fortnight each boat. As a result it was decided to use Platypus as a Depot Ship at Garden Island, acting also as parent ship for the submarines.

Platypus paid off on 15 August 1929 and the following day commissioned as HMAS Penguin. In April 1931 Otway (I) and Oxley (I) were transferred to the Royal Navy.

Platypus continued in service as the Depot Ship at Garden Island, Sydney, under the name of Penguin until 26 February 1941 when she recommissioned as HMAS Platypus to resume seagoing service as a training ship.

In May 1941 she proceeded to Darwin. She was present in Darwin Harbour on 19 February 1942 when Japanese carrier borne aircraft made the first air attack on Australian soil. According to the official history of the Royal Australian Navy in World War II, ‘Platypus fought back hard, and though near-missed three times and with the lugger Mavie alongside her sunk escaped with damage in the engine room which immobilised her for some time.’

She remained in service as Base Ship, Darwin, until 1 January 1943 when she sailed for Cairns where she again served as Base Ship until May 1944.

At Williamstown, Victoria, on 12 June 1944, Platypus commenced a major refit and conversion of two of her four boilers to oil burning. The refit was completed in December 1944. On 5 January 1945 she left Sydney to proceed to New Guinea for service as a Repair and Maintenance Vessel.

Platypus operated in the Madang, Hollandia and Morotai areas until the end of November 1945, returning to Australian waters in December 1945. On 12 February 1946 she departed Melbourne for Sydney on her final sea voyage under her own power. Platypus paid off into Reserve at Sydney on 13 May 1946.

Platypus was sold on 20 February 1958 to Mitsubishi Shoji Kaisha Ltd, of Tokyo, Japan, for scrap. In June 1958 the Japanese salvage vessel Tukoshima Maru departed Sydney for Japan with Platypus and the former Bathurst Class minesweeper, HMAS Dubbo (I), in tow.

HMAS Platypus alongside the two Odin Class Submarines, HMAS Oxley and HMAS Otway
HMAS Platypus alongside with the two Odin Class Submarines, HMAS Oxley and HMAS Otway outboard of her.