Juno Beach Centre | Canada in WWII
Events | The Canadians in Order of Battle
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Submarines attack in the St. Lawrence
HMCS Assiniboine and the destruction of U-210
Western Approaches Tactical Policy, April 1943

During the night of 11th to 12th May, 1942, the inhabitants of Cloridorme, a fishing community in the Gaspé Peninsula, were awakened by an explosion that shook up their houses as an earthquake may have done. Some lights could be seen out at sea, then vanished; in the morning, lifeboats drifted ashore. After several hours of searching, 111 survivors were rescued, seven men are missing.

The attack made the headlines and public opinion was alarmed. A threat that no one had dared mention until then, had just materialized: German U-boats in the Gulf of St. Lawrence; Nazi Germany threatening Canada from within. Public opinion demands an explanation and protests against censorship.

German submarine U-553, under Kapitänleutnant Karl Thurmann, lying in ambush in the Gulf's dark waters, had torpedoed two Dutch freighters, Nicoya and Leto. This first attack in the Gulf was to be followed by several others. The coastline affords many hiding-places for an ambushed submarine; in addition, the ASDIC (sonar detection) system is rendered useless by the fact that in the Gulf, water presents layers of contrasting temperatures. Between May and November 1942, 18 ships are sunk in the River and in the Gulf, including two RCN (Royal Canadian Navy) vessels. On November 9th, 1942, a German spy, Alfred Waldmar von Janowski, is brought to shore by U-518 in New Carlisle. Apparently lacking the required discretion, he was rapidly found out and intercepted by the police.

Consolidated Canso flying boats were flown by RCAF crews patrolling the Atlantic and the St. Lawrence coasts. Canso 9798 of 160 (BR) Squadron, RCAF, is shown during mercy flight in Newfoundland, 13 October 1944.
National Archives of Canada, PA-070818.

Defence measures are upgraded. The RCN sets up a convoy system to protect freighters and creates an escort force based in Quebec City, made up of smaller ships: Bangor-class mine sweepers, Fairmiles, and armed yachts. The Royal Canadian Air Force (RCAF) increases the frequency of its air patrols. 117 (BR) Squadron is detached from its Dartmouth base and three or four of Canso flying boats are sent to Gaspé to take part in the operations in the Gulf. Meanwhile, the other flying boats from 117 (BR) Squadron and several Hudsons from 113 (BR) Squadron monitor the eastern sector, at the entrance of the Gulf.

"The U-Boat was on the surface heading 240° moving at 8-10 knots. Pilot throttled back fully and dove, manoeuvering to attack from astern dead along track of U-Boat."
Attack on U-754 by Hudson 625 of 113 (BR) Squadron, July 31st, 1942

Some submarines were sighted but almost invariably managed to escape air and naval patrols. Only one, U-754, is destroyed by a Hudson from 113 Squadron off Nova Scotia on July 31st, 1942. The Canadian government does not seem to believe in the efficiency of these measures and responds to criticism without much conviction. The German perception of the situation was, however, quite different: having been often detected by Canadian patrols, the enemy overestimated the actual efficiency of the Canadian coastal defence. On debriefing to their Commander-in-Chief, Admiral Dönitz, German U-boat commanders present incursions in Canadian territorial waters as a major risk. As a result, in the fall of 1942, Dönitz decides to discontinue submarine warfare in the St. Lawrence. Unknowingly, Canada has won a battle against the enemy.

Unfortunately, that success was to have a tragic conclusion: expelled from the St. Lawrence River by Canadian patrols, U-69 cut across the route of the ferry linking North Sydney, Nova Scotia, with Port-au-Basques, Newfoundland. On October 13th, 1942, it surfaced under a moonless sky, and attacked the ferry, S.S. Caribou, unseen from her escort, HMCS Grandmère. At 0321 on the 14th, it fired on the ferry: Caribou sank so fast that only one lifeboat could be launched. Of the 237 persons on board, only 101 survived. All 46 crew members perished.

Restructuring the Escort Forces

For Canadians and their political representatives, German incursions into the Gulf were events of unprecedented gravity. Actually, this was nothing in comparison with the crisis facing Allied navies.

Until 1941, U-boats had stayed away from U.S. shores to avoid giving America a reason to join the war against Nazi Germany. But the December 7th, 1941, Japanese attack on Pearl Harbor resulted in direct U.S. military involvement: Admiral Dönitz was now free to attack unescorted freighters and tankers in U.S. territorial waters. At the end of December 1941 and in January 1942, Germany launched two attacks in the western half of the North Atlantic, a stretch of ocean where unescorted merchant ships were an easy prey. Two groups, one made of five Type-IX, long-range U-boats, and a second one of six, smaller, Type-VII submarines, were tasked with attacking all ships sailing from Sydney, Halifax, Boston, New York or Cape Hatteras, with an objective of destroying as many as possible. As a countermeasure, unofficial convoys were rapidly organized and available warships sent to protect them.

This shift to targets in North American waters forces the Allies to restructure their escort forces. In February 1942, the Newfoundland Escort Force (NEF) and the US escort forces are grouped under the common designation of "Mid-Ocean Escort Force" (MOEF). That force is comprised of 12 groups of six ships each (two destroyers or equivalent, and four corvettes). The five "B" groups (British) and the four "C" groups (Canadian) are based in St. John's, while the three "A" groups (U.S.) use the Argentia, Newfoundland, naval base. Convoys now follow a more southerly route and MOEF escort ships operate between St. John's and Londonderry, in Northern Ireland. Escort commanders are instructed to remain in close contact with their convoy to ensure protection at all times; rescuing imperiled ships or hunting down enemy submarines must never deprive the convoy of a needed escort.

Survivors of torpedoed merchant ship aboard HMCS Arvida, 15 September 1942.
Department of National Defence / National Archives of Canada, PA-136285.

Canadians also had to protect convoys destined to Murmansk and Arkhangelsk in the USSR. For the Third Reich had turned against its former ally, which it attacked on June 22nd, 1941; for months, nothing could stop the advance of German forces into Russian territory but the cold: the formidable Nazi war machine came to a halt with winter. There was still some hope to save Russia. Winston Churchill believed that Russia's resistance against the onslaught of German forces could only weaken the common enemy. As a result, he suggested to US President Roosevelt that the Allies unite with Stalin and supply communist Russia with all it needed to fight. That material - tanks, airplanes, trucks, jeeps, explosives, weapons, shoes, radios - had to be shipped from Loch Ewe in Scotland or from Reykjavik in Iceland to Murmansk or Arkhangelsk. The sea route to Murmansk was 1600 kilometres long and left a definite impression on the sailors who took it. During the short summer, the days were almost 24 hours long, which favoured German aircraft, ships and submarines. In the dark of the winter, the violent storms and the ice that built up everywhere on the ships were even more dangerous.

In February 1942, the Western Local Escort Force (WLEF) is also created to ensure protection of merchant ships between Halifax and the meeting point, off Cape Race, Newfoundland, where MOEF ships take over for the Atlantic crossing. As air and naval defence against U-boats along Canadian coats improves, German submarines move further south and, in March, ships need to form convoys for the Boston-Halifax leg of the trip as well.

"I closed U-boat to ram at full speed. He opened fire with all his guns and for about 35 minutes the action continued at a point blank range of about 100 to 300 yards. A second degree fire broke out…"
HCMS Assiniboine and the destruction of U-210.

With such a massive deployment going on, neither the RCN nor the RCAF have much time left for modernizing their equipment, or even ensuring regular maintenance. Repeated operations infringe on the normal rest periods of crews and training suffers as well. Resources are already stretched when, in the summer of 1942, U-boats start entering the Gulf of St. Lawrence to launch torpedo attacks.

The RCN Under Fire

Map: Ships Sunk

In the Atlantic, U-boats inflict major damages and casualties to Allied navies. The Kriegsmarine increases its submarine fleet and, in the fall of 1942, has some 200 U-boats (compared to 91 when the year started). Of those 200 submarines, more than a hundred operate in the Atlantic, of those some 45 are on patrol duties at any given time, while 60 are sailing towards or from their operation theatres.

Starting in September 1942, convoys leave from New York rather than Halifax, forcing merchant ships in Canadian ports to form smaller convoys from Saint-John in New Brunswick, Halifax and Sydney in Nova Scotia, and Newfoundland ports, until they reach the meeting point off Cape Race where they are integrated in larger trans-oceanic convoys. The WLEF is tasked with escort duties from New York to Cape Race, a distance of 1,800 kilometres, i.e. more than half the 3,300 kilometres separating Newfoundland from Northern Ireland. Several WLEF ships cannot sail the whole distance and must leave the convoy to refuel in Halifax while others take over.

Royal Navy and RCN destroyers and corvettes alongside Jetty No. 4, HMC Dockyard, Halifax, 16 October 1942.
Photo by Jackson G. Kempster. Department of National Defence / National Archives of Canada, PA-106063.  

These measures are effective and drive U-boats back towards the mid-Atlantic sector. In the fall of 1942, Germany nevertheless still has several advantages over the Allies: Allied aircraft do not have the range to patrol the whole Atlantic route from their Newfoundland, Iceland or British bases, leaving an unprotected area south of Greenland, the "black pit", from which U-boats benefit. Moreover, a recent modification to the Enigma encryption machine has made U-boat radio communications once again unexploitable by the British cryptological services, while Germany has broken the British Number Three Code, used for communications with convoys. The situation appears so desperate that in November 1942, Churchill creates an anti-submarine warfare committee, that he chairs himself. Admiral Sir Max Horton is appointed Commander-in-Chief of Western Approaches Command.

The safe and timely arrival of the convoy at its destination is the primary object of the escort. Evasion attains the primary object and should therefore be the first course of action considered. The object as laid down has been the subject of a good deal of criticism on the grounds that it is not offensive enough.
-Admiral Max Horton, Western Approaches Tactical Policy, April 1943.

The stern of HMCS Saguenay was blown off by the explosion of its depth charges after being rammed by a freighter on 15 November 1942. The destroyer could not be made seaworthy and was later used as a training ship.
Photo by John D. Mahoney. Department of National Defence / National Archives of Canada, PA-153500.

For Canadians, the situation keeps getting worse: the RCN has lost three destroyers in the fall of 1942: Ottawa, sunk by U-91 on September 13th; St. Croix, torpedoed and sunk by U-305 on September 20th; and Saguenay, damaged out of commission on November 15th, when her depth charges exploded after she was accidentally rammed by a freighter. In addition, Assiniboine must be dry-docked for an extended period of time following action against U-210 on August 2nd. The RCN's escort fleet cannot meet the demand. For lack of time, its ships are not as well maintained as those of the Royal Navy or the U.S. Navy, and mechanical breakdowns are more frequent. Crews suffer from fatigue, and lack experience and technical training.

The Western Approaches Command officers' opinion of Canadian escort groups is quite negative, as they are considered the less effective of all three allies. On December 17th, 1942, Churchill sends a telegram to King, asking that Canada take over the less dangerous Great Britain-Gibraltar route, which amounts practically to requesting Canada's withdrawal from the MOEF. The RCN staff is furious, and considers that Great Britain is - to a large extent - responsible for that state of affairs. The Royal Navy, while continually requesting additional support from the RCN, has not provided its Canadian counterpart with the state-of-the-art navigational equipment and armament found on its own ships.

Unfortunately events bring more misfortunes on the Canadian escort groups. Between December 25th and 29th, 1942, convoy ONS-154, under the protection of Canadian escort group C1, loses 14 ships to an attack by a large U-boat pack. C1 had only one destroyer, HMCS Saint-Laurent, as the second one was unable to get under way. Although it has gained in experience, C1 still lacks cohesion when working as a combat unit, a situation resulting from frequent changes of crew imposed by emergency situations. The RCN must face the fact that Canadian escort groups need more training.

At the end of 1942, the situation appears desperate. The Battle of the Atlantic is raging, the enemy seems invincible and casualties are mounting. And yet, within a few months, things will change dramatically.

Next: HMCS Assiniboine and the destruction of U-210