HMCS Baddeck and Convoy SC-48
	HMCS Moose Jaw and the sinking of U-501

The Submarine Threat

Fall 1940: prowling like wolves through the North Atlantic, German U-boats are hunting for Allied merchant navy convoys. As soon as a U-boat locates a target, she sends its coordinates to her HQ and start stalking her prey. Other U-boats in the area, notified by radio, zero in on the target. A pack is formed. The German submarines' low profile makes them almost invisible on the surface of the sea, while the towering shapes of merchant vessels and of their escort ships are easily spotted against the sky. When signal is given, at night, the U-boats attack. A first blaze lights up the sky: a torpedoed ship is sinking. While the escort ships try to intercept the attacker and rescue survivors, other submarines get closer and start firing; some may even be daring enough to slip through the convoy's columns. Attacking while on the surface allows U-boats to make full use of their speed and manoeuvrability. As soon as they are located, they dive and disappear in the deep.

German U-boat U-210 from HMCS Assiniboine during attack that let to its sinking 6 August 1942. Photo by G.E. Salter. Department of National Defence / National Archives of Canada, PA-037443.

This is the terribly efficient "wolf pack" tactic, developed by German Admiral Karl Dönitz. Between October 17th and 19th, 1940, seven U-boats attacked convoy SC-7 and sank 22 of its 34 ships. Dönitz's ambition was that no supply and equipment shipment should reach the British Isles by sea.

Ships and More Ships…

At sea, war starts as early as September 3rd, 1939, the very day that Great Britain and France declared war. On that day, the German submarine U-30 sank a British liner, Athenia, which was making for Montreal with 1103 passengers and 115 crew on board. There are 128 dead, including four Canadians. Public opinion is shaken by such a ruthless attack on the very first day. War at sea was to be expected as well as on the ground, but under the sea? Neither the public nor the Allies know yet that, actually, the overzealous commander of U-30 had exceeded his ordersÉ

At that time, the British Admiralty and the Royal Canadian Navy (RCN) are already working together to build a naval force that can keep the German war navy in check. Having learned from their WWI experience, they know how deadly U-boats can be. They are also well aware of the threat posed by conventional German warships. As a result, in the last days of peace, they have taken measures to ensure close cooperation and protect shipping routes by organizing merchant navy convoys.

Determined to preserve national sovereignty, the King government makes protecting Canadian shores its priority. But the RCN does not have enough ships to patrol Canadian coastal waters, let alone respond to the Royal Navy's request for assistance. Destroyers are bought from Great Britain, as well as merchant ships, to be converted into warships. War demands that Canada's shipbuilding industry be revived: in 1940 the government gives its approval for the construction of 90 small warships, the Flower-class corvettes and the Bangor-class minesweepers. The Royal Canadian Air Force (RCAF) also plays a role in protecting coastal areas and air patrols become more frequent. In 1939, forces at the Dartmouth Air Base are increased and airfields are constructed in Sydney and Yarmouth.

Building a corvette at Davie Shipbuilding in Lauzon, near Quebec City, April 1941. National Defence Image Library, PMR 83-1674.

Convoys: Danger Comes from the East

The first convoy, HX-1, sails from Halifax on September 16th, 1939, and reaches Great Britain safely. Merchant ships are still relatively safe when they leave North American harbours as Germany has only 24 short-range U-boats, based in the North Sea. Their hunting grounds are mostly the waters surrounding the British Isles. Canadian escort ships accompany tankers and freighters up to a point off the coast of Newfoundland, where the Royal Navy takes over.

A convoy of merchant ships assembling in Bedford Basin, Halifax, April 1941. Department of National Defence / National Archives of Canada, PA-105262.

Map: Convoy Route 1939

The situation will deteriorate, however, when German armies reach the shores of the Channel. In May 1940, an invasion of Great Britain becomes a definite possibility. During the summer of 1940, the Royal Navy must therefore redeploy its ships to protect British coasts and ensure the safe evacuation of troops across the Channel. As a result, it has to reduce the level of protection afforded to transatlantic convoys. With terrifying speed and efficiency, U-boats sink poorly defended merchant ships: while 200 ships were sunk during the first nine months of war, that number increased to 350 during the second half of 1940.

The RCN was also called upon to take part in naval action in the weeks leading to the fall of France. Four of its seven destroyers are sent to the British Isles to support the Royal Navy and, starting June 9th, 1940, HMCS Restigouche, Skeena, St-Laurent and Fraser shuttle across the Channel to evacuate the remaining Allied troops. The RCN suffers its first major casualties when HMS Calcutta accidentally rams Fraser. Not only is the Canadian destroyer out of commission, but 47 Canadian crew and evacuated British soldiers lose their lives.

After the fall of France in June 1940, the Kriegsmarine (German war navy) occupies French naval bases in Brest, Lorient and Saint-Nazaire. From these Atlantic bases, German submarines can now launch attacks on Allied convoys without having first to cross the North Sea and the Channel patrolled by the Royal Navy. As they did during the Battle of Britain, the British improve dramatically their anti-submarine warfare equipment and strategy, and multiply both air and sea patrols. As it becomes increasingly difficult for German submarines to venture into North Ireland waters - a favorite route for convoys reaching the British Isles - Admiral Dšnitz decides to shift the theatre of operations westwards, towards the centre of the Atlantic Ocean, an area that the Allies cannot protect as easily. This is where the wolf pack strategy was developed.

The Newfoundland Escort Force (NEF)

View from HMCS Chambly of the first flotilla of Canadian-built corvettes en route from Halifax to St. John's, Newfoundland, 23 May 1941. Department of National Defence / National Archives of Canada, PA-037447.

Casualties and material damage suffered by Canadians on account of U-boats during the winter of 1940-1941 are evidence enough that escort protection had to be reinforced and implemented all along the transatlantic route. In May 1942, the British Admiralty asks RCN Chief of Staff Admiral Percy Nelles, to provide convoy protection for the whole Western half of the North Atlantic. The Newfoundland Escort Force (NEF) is set up under Commodore L.W. Murray, with its HQ in St. John's where a new naval base is built.

The NEF benefits from US destroyers obtained by Canada in exchange for allowing the US to use Canadian ground bases and some of the first Canadian-made corvettes. Canadian and British ships assigned to the NEF sail from Halifax or Sydney to join fast (HX) or slow (SC) convoys off the coast of Newfoundland; they will escort them until near the coasts of Iceland, where Royal Navy escort vessels take over. NEF ships then make a stop at the Hafnarfjordur naval base, near Reykjavik (Iceland) to take in fresh supplies. On the way home, they escort westbound (ON) convoys to a point off the coast of Newfoundland, and then to St. John's.

Map: Convoy Route 1941

Despite all their efforts, their submarine detection systems and their armament, Canadian escort ships were definitively no match for U-boats. In the event that the ASDIC operator was able to locate a submerged submarine, two ships working as a team may have a chance to drop a depth charge close enough to cause some damage. A speedier tactic was to try to ram the submarine before she could dive.

Convoy attacked, apparently ship in rear of third or fourth column torpedoed. Increased to 140 revolutions (best speed) and closed to within 500 yards of convoy then opened searchingÉ
HMCS Baddeck and Convoy SC-48

I saw a submarine surface between Chambly and ourselves, which appeared to be stopped. The submarine made a series of "I'S" on a small lamp just abaft the conning tower. It got under weigh at this point, and I gave chase, opening fire with the 4-inch gun as soon as it was clear of Chambly...
Lt. F.E. Grubb, Commanding Officer HMCS Moose Jaw

Given the urgency of the situation, Canadian escort ships, including new corvettes, are launched as rapidly as possible, despite the lack of experience and training of their crews. All too often, they prove unable to intercept a submarine which slips away rapidly after an unexpected and devastating attack. Canadian sailors can only try to rescue as many survivors and save as many lives as possible. Already facing difficult living conditions, North Atlantic storms and the exacting demands of escort operations, these brave men cannot but feel helpless when ships under their protection are blown up before their eyes or when they see the lights on the lifejackets of shipwrecked sailors fade away into the night…