The Hill class looked remarkably like a fishing vessel but carried a 4-inch gun and roughly fifty-five depth charges. That load made the trawler dangerous to submarines even though the hull itself was a poor use of a torpedo. An attack would consume a valuable weapon, reveal the U-boat's position, and bring other escorts into the hunt. Although designed mainly for coastal service, some trawlers completed Atlantic voyages. Endurance figures vary because individual vessels had coal-fired or oil-fired machinery. Those crossings likely required extra fuel aboard, Royal Fleet Auxiliary support, or both.
Chapter · 11:03-13:37
Why a Hill-class trawler complicated a U-boat attack
A lightly armed trawler could deter submarines by carrying depth charges and making any torpedo attack costly, revealing, and strategically inefficient.