"flak ship" . "auxiliary patrol vessel" . "ASW trawler" . "HM Trawler ''Arkwright''" . "Anti-submarine trawlers" . "Armed Trawlers" . "trawlers" . . "anti-submarine trawler" . . "Royal Navy trawler" . "Trawler No 328" . "Trawlers of the Royal Navy" . "conversions of ships" . . . . "trawler" . "British armed naval trawler" . "HMT" . "Trawlers of the Royal Navy" . "trawlers of the Royal Navy" .