- Sinfield, Peter
- WWI operations, Early warships, RAN operations, Ship design and development
- RAN Ships
- HMAS Geranium, HMAS Marguerite, HMAS Mallow
- September 2004 edition of the Naval Historical Review (all rights reserved)
The first dedicated minesweeping vessels in the RAN made their appearance in Australian waters at the end of WW1 to sweep minefields sown by a German raider during the war, and subsequently served as surveying sloops.
On 8 June 1919 three grey ships steamed slowly up Sydney Harbour to Garden Island. Their mercantile lines and unusual names – Geranium, Mallow and Marguerite – seemed at odds with the White Ensigns fluttering from the gaffs of their mainmasts, but they were the first purpose-built minesweepers to serve in Australian waters.
The three vessels were Fleet sweeping sloops of the Flower class, built in England under the Admiralty’s Emergency War Programme. Despite the mine having been in service for nearly half a century and the lessons of the Russo-Japanese War a decade before, the Royal Navy had virtually ignored the need for minesweeping. When war broke out in August 1914, its total minesweeping force consisted of 10 converted torpedo gunboats and 13 requisitioned trawlers, but early losses (including the scout cruiser HMS Amphion just two days after war was declared and the new Dreadnought battleship HMS Audacious in October) quickly made the point.
In the first half of 1915 orders were placed for the first three types of the Flower class sloops (72 vessels in all), with all but a handful being launched by the end of the same year. Like the corvettes and frigates of a later generation, their speed of construction was largely due to the adoption of good mercantile practice (rather than the stricter Admiralty requirements) and the distribution of orders to smaller, non-specialist shipyards. The Acacia, Azalea and Arabis types had a displacement of 1,200-1,250 tons, around 265 feet in length, with a single screw and speed of 16-17 knots. Main armament was one 4-in in Mallow and Marguerite, and a 4.7-in in Geranium.
By the time the sloops arrived, the need for them was some two years old. In late June and early July 1917, the German commerce raider Wolf laid three minefields in Australasian waters – one off the northern tip of New Zealand, a second in the western mouth of Cook Strait (between New Zealand’s North and South Islands), and the third off Cape Howe (where the Victorian-NSW border meets the Tasman Sea). A mine from the latter field led to the loss of SS Cumberland early in July, and on the 17th of that month the Minesweeping Section of the Royal Australian Naval Brigade was established. On 8 October, the trawlers Gunudaal and Koraaga – requisitioned from the NSW Government and manned by the RANB – began the sweep off Gabo Island. One mine was swept on the 9th, and another three days later. Sweeping continued for nearly three months, during which time Gunudaal and Koraaga were joined by the trawler Brolga and the tug Cecil Rhodes. By 3 January 1918 a total of 13 mines had been found, but no more were discovered in the following five weeks and the sweep was abandoned on 12 February. Following further sightings, however, Gunundaal and the tug Champion conducted another sweep in September and October 1918. This was unsuccessful, but three weeks later a mine was destroyed off Moruya. .
After the Armistice, the Naval Board (ACNB) asked the Admiralty if more information could be ascertained from surrendered German charts. The response indicated two fields of 15 mines each, the northernmost of which had been laid off Cape Everard and the existence of which had, until that time, been totally unsuspected. Consequently, a further sweep was organised during January 1919, using the steamer Coogee and the tug James Paterson. Again this was unsuccessful, but a drifting mine was destroyed in the area a month later. Yet another sweep was ordered, this time conducted by the elderly Protector between 10 March and 4 April. No mines were located, but in June a drifting mine was washed ashore and exploded near Cape Everard.
In the intervening period, HM Ships Geranium, Mallow and Marguerite were on passage to New Zealand, to sweep the fields laid by Wolf off the Three Kings group and Cape Farewell. ACNB therefore requested that, on completion of this task, the ships re-sweep the Cape Everard field. This was done between the 8th and 20th September 1919 (for one mine), after which the ships sailed for Sydney and paid off on 18 October.
The three sloops were then presented to Australia, presumably as the nucleus of a local minesweeping force. However, Geranium spent eight years (1920-27) as a survey ship, carrying a Fairey HID seaplane during 1924. Marguerite was employed for nine and a half years on fleet and Reserve duties, but Mallow spent most of her RAN career in reserve, only being commissioned during 1924-25 for RANR training.
All three vessels paid off for the final time in the mid to late 1920s and remained in reserve until 1932. They were then handed to Cockatoo Island Dockyard to be stripped before being expended as targets off Sydney in 1935.