Frederick John Walker

Captain Frederick John Walker, known as "Johnnie," was the Royal Navy's most successful U-boat hunter of the war, personally responsible for the destruction of more U-boats than any other commander. Based in Liverpool, his 2nd Escort Group (later 36th) developed innovative "creeping attack" tactics that transformed anti-submarine warfare. His methods involved one ship maintaining sonar contact while another crept ahead at slow speed to depth-charge the submarine from ahead — a position from which U-boats could not detect the attack. Walker and his ships sank at least 20 U-boats. He died of a cerebral haemorrhage in July 1944, worn out by the strain of continuous operations. Liverpool gave him a public funeral, one of the largest in the city's history.