A typical armed trawler could carry a four-inch or twelve-pounder gun, Oerlikons, and depth charges despite being far slower than a purpose-built warship. Vessels acquired mainly for harbour defence were sent wherever operations required them. About 200 helped fill the escort gap during a Battle of the Atlantic in which the Allies lost 175 warships, so every usable hull mattered. The larger, 843-ton ocean-going type made only about twelve and a half knots, half a knot faster than Ayrshire, but officially carried more depth charges than an original Flower. Their numbers and weapons made these modest ships indispensable to convoy defence.
Notable Point · 18:13-20:38
Trawlers as the convoy war's mass escort force
Trawlers intended mainly for harbour defence became indispensable convoy escorts because the scale of wartime losses made hundreds of small vessels militarily necessary.