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J7 Submarine

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Fighting WWI Submarine to Marina Breakwater

J7 Submarine
J7 Submarine
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The J7 Submarine at Sandringham Yacht Club is a unique visible feature of the marina, and is historically significant as one of the Royal Australian Navy's earliest submarines, predated only by the AE-1 and AE-2.


The J class of submarines was a seven submarine class developed by Britain's Royal Navy prior to the First World War in response to claims that Germany was developing submarines that were fast enough (22 knts) to operate alongside surface fleets. The rumours were actually false. Six J class submarines were completed during mid-1916, while a seventh entered service at the end of 1917.

The J class Submarine Number 7 was built in Devonport Dee and completed 11/1917. In that time the J class were the fastest subs in existence. Number 7 was the last J class submarine to be built.

Although larger and more powerful than previous British submarines, the J class could not keep up with surface vessels, and operated independently during the war. Between them, the submarines sank a U-boat, and heavily damaged two battleships, with the loss of one, the J6, to friendly shelling. They were equipped with a powerful long-range wireless they were ideally suited to reconnoiter in enemy water.

Following the war, the six surviving submarines were gifted to the Royal Australian Navy. When they arrived in Australia, they were all in poor condition. The boats were not refitted in England before being handed over and sailing to Australia, and had to undergo extensive refits. They were immediately refitted (from 1920) at the Garden and Cockatoo Island Commonwealth Naval Dockyards. The last one to be refitted was the J7 submarine in June 1922.

The ironclad Cerberus acted as a depot ship to the J Class submarines whilst they were stationed at Geelong.

The decision to scrap the J7 submarine came on the 16-Jan-1924 even though it was in fairly good condition after just being refitted. It was described as the last survivor of an obsolete class. She stayed in service for the longest period providing electricity for the Flinders Naval Depot.

She was towed from Cowes where she had been lying at anchor, to Melbourne by the tug Minah and broken up at Footscray. The J7 was sold to Morris and Watts Machinery Merchant in October 1929, who after dismantling the J7 sold it to the Ports and Harbors Department Melbourne and sunk her as a breakwater at Sandringham Yacht Club in August 1930.

Four subs, J1, J2, J4, and J5, were scuttled in the ship graveyard. Two were scuttled as breakwaters: J3 near Swan Island, and J7 at Sandringham Yacht Club.

See also, Australian National Shipwreck Database: J-7 Submarine,
Sandringham Yacht Club: J7 Submarine, and
Heritage Council Victoria: J-7 Submarine.

Latitude: 37° 56.683′ S   (37.944722° S / 37° 56′ 41″ S)
Longitude: 144° 59.600′ E   (144.993333° E / 144° 59′ 36″ E)

Datum: WGS84 | Google Map
Added: 2012-07-22 01:00:00 GMT, Last updated: 2019-03-23 02:17:08 GMT
Source: GPS
Nearest Neighbour: Sandringham Pier Breakwater, 101 m, bearing 88°, E
J-Class Submarine, 1820 ton.
Built: Dyfed, Wales, 1916.
Scuttled: 6 August 1930.

DISCLAIMER: No claim is made by The Scuba Doctor as to the accuracy of the dive site coordinates listed here. Should anyone decide to use these GPS marks to locate and dive on a site, they do so entirely at their own risk. Always verify against other sources.

The marks come from numerous sources including commercial operators, independent dive clubs, reference works, and active divers. Some are known to be accurate, while others may not be. Some GPS marks may even have come from maps using the AGD66 datum, and thus may need be converted to the WGS84 datum. To distinguish between the possible accuracy of the dive site marks, we've tried to give each mark a source of GPS, Google Earth, or unknown.

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