A naval trawler is a vessel built along the lines of a fishing trawler but fitted out for naval purposes. Naval trawlers were widely used during the First and Second world wars. Fishing trawlers were particularly suited for many naval requirements because they were robust boats designed to work heavy trawls in all types of weather and had large clear working decks. One could create a mine sweeper simply by replacing the trawl with a mine sweep. Adding depth charge racks on the deck, asdic below, and a 4-inch gun in the bows equipped the trawler for anti-submarine duties.
Armed trawlers were also used to defend fishing groups from enemy aircraft or submarines. The smallest civilian trawlers were converted to danlayers.
|“||The naval trawler is a concept for expeditiously converting a nation's fishing boats and fishermen to military assets. England used trawlers to maintain control of seaward approaches to major harbors. No one knew these waters as well as local fishermen, and the trawler was the ship type these fishermen understood and could operate effectively without further instruction. The Royal Navy maintained a small inventory of trawlers in peacetime, but requisitioned much larger numbers of civilian trawlers in wartime. The larger and newer trawlers and whalers were converted for antisubmarine use and the older and smaller trawlers were converted to minesweepers||”|
The Royal Navy ordered many naval trawlers to Admiralty specifications. Shipyards such as Smiths Dock Company that were used to building fishing trawlers could easily switch to constructing naval versions. As a bonus, the Admiralty could sell these trawlers to commercial fishing interests when the wars ended. Still, many were sunk during the war, such as HMT Amethyst and HMT Force.
In 1940, Lieutenant Richard Stannard was in command of the naval trawler HMT Arab when he won the Victoria Cross for his actions from 28 April to 2 May 1940 at Namsos, Norway. HMT Arab survived 31 bombing attacks in five days.
Some nations still use armed trawlers today for fisheries protection and patrol. North Korea has been notoriously known for its use of armed trawlers as spy ships. The Battle of Amami-Ōshima was an incident in which the Japanese sank a North Korean naval trawler after a six hour battle. Somali pirates have also commandeered trawlers and armed them for attacking freighters off of the Horn of Africa. The Action of 18 March 2006 is one example of pirate use of a naval trawler. The pirates used naval trawlers again at the Action of 30 March 2010 and the Action of 1 April 2010. One naval trawler was sunk and another was captured by the Seychelles Coast Guard and a U.S. Navy frigate.
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- Lund, Paul and Ludlam, Harry (1971) The Trawlers go to War ISBN 978-0572007683
- Lund, Paul and Ludlam, Harry (1978) Out Sweeps! - The Story of the Minesweepers in World War II. New English Library Ltd ISBN 9780450044687
- McKee, Alexander (1973) The Coal-Scuttle Brigade : The splendid, dramatic story of the Channel convoys. New English Library ASIN B000RTAX2Y
- The Trawlers go to War
- A/S Trawlers (uboat.net)
- Memorial site to a trawler skipper
- The Battle of Mesco Point
- The Dover Convoys