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The Sheep Dog Navy: Navy, Part 39

HMCS Arrowhead  off Nova Scotia, 1942. [PHOTO: LIBRARY AND ARCHIVES CANADA—PA136840]

HMCS Arrowhead off Nova Scotia, 1942.

Going To War With What You’ve Got

American entry into the war in December 1941 promised eventual allied victory: Churchill claimed he slept well for the first night in years when he heard of the Japanese attack on Pearl Harbor. But it would be at least a year—and more like two—before America’s potential could tip the balance. For the moment, the Allies scrambled to contain Japan’s astonishing advances in Asia and the South Pacific. Only the British and Americans had the aircraft carriers, battleships and cruisers capable of stopping them. Moreover, this had to be done while holding off the still powerful German and Italian fleets in European waters.

Not surprisingly, when Royal Canadian Navy planners looked at the prospects for 1942 they resigned themselves to a supporting role. But how the Canadian navy contributed to this ‘patch and fill defence’ was unclear. “Relieving the RN and USN of duties and the loan of ships,” an RCN planning document observed in January, “depends on circumstances outside the control of the RCN.” In the event, the only relief that the Canadian navy could offer its larger partners in 1942 was to take on a greater share of convoy escort duty in the North Atlantic. Up to this point, only Commodore Leonard Murray, the Newfoundland Escort Force commander—and perhaps a handful of others—had been prescient enough to see that the future of the RCN in the Second World War lay with the Sheep Dog Navy. By early 1942 the whole service was confronted with the idea that convoy escort and anti-submarine operations were likely to be its primary task for the foreseeable future.

It is fair to say that the RCN was not ready for this burden, and in retrospect 1941 looks like a lost year. Indeed, so far the RCN had never thought of the Sheep Dog Navy as anything more than a sidebar to its real ambitions to join in fleet actions. Corvettes were to be built, used and discarded. For example, the RCN was well aware in late 1940 that the British were modifying the original corvette design to adapt it to oceanic convoy duty. The RCN declined to follow their lead. At the end of 1940 only four Canadian-built corvettes were in commission, and only three more were in the final stages of fitting out or conducting trials. At least 70 others, still fully in their builders’ hands, might have been modified based on the latest British experience before they were commissioned. These changes included simply extending the forecastle to make corvettes more seaworthy and habitable, and rebuilding their bridges to carry heavier secondary armament. Fitting modern weapons and sensors like radar and improved asdic was more ambitious, not least because that equipment would have to come from Britain. In the Canadian case, this would also include installing a low-power electrical system to run the gyro compasses needed for modern asdic.

But in late 1940 the RCN’s corvette fleet—as designed—was perfectly adequate for the tasks envisaged for them. Most of the first 54 being built for the RCN were to be assigned to Canada’s system of defended ports, where their “jack-of-all-trades, master-of-none” character was ideal. The balance of the first RCN building program would be sent overseas to operate with the British, where it was assumed they would quickly find suitable work. The 10 corvettes building in Canada to British contracts were the RN’s business. The complex Canadian system of contracting for vessels also militated against substantive changes. Interposed between the navy and the yards lay the Department of Munitions and Supply that had to authorize all changes to the original contracts. This meant that RCN naval engineers could not simply visit a yard and ask that the forecastles or bridge wings be extended, or that a lower power system be installed.

So the RCN was content at the end of 1940 to leave its initial corvette program alone, and let it get to sea. That said, the RCN did adopt changes for the corvettes of its small 1940 program. The least obvious was the switch from Scotch marine boilers to water-tube boilers. The drum-shaped Scotch boilers held a massive amount of water, which was turned to steam by passing heat from the firebox through pipes that snaked through the standing water in the boiler. This provided a powerful and ready reserve of steam for short bursts of maximum speed—just enough for a sprint to catch a submarine. But maintaining steady and reliable cruising speed over long periods of time was problematic. The water-tube boilers adopted for the 1940—and subsequent—escort building programs saved space and operated more efficiently. In such boilers, the water passed through the firebox in pipes. The result was an ability to raise steam quickly, more reliable performance, less weight and significantly smaller boilers. Although the 1940 program saved space by adopting water-tube boilers, that space was not used for increased fuel storage—as it would be in mid-war building programs—and therefore increased range.

Minesweeping equipment lines the jetty, Halifax 1942. [PHOTO: G.A. LAWRENCE, LIBRARY AND ARCHIVES CANADA—PA106515]

Minesweeping equipment lines the jetty, Halifax 1942.

The first six of the 1940 corvette program were too advanced to change much else. They emerged in virtually identical form to the 1939 program ships, except for the deletion of minesweeping gear that dominated the quarterdecks of the first 54 RCN corvettes. With a large program of Bangor class minesweepers underway, the navy’s needs in this category would soon be met. However, the last 10 corvettes of the 1940 program had not yet been laid down by the end of the year, and so major modifications were possible with this group. These included a completely designed hull, with increased shear and flare forward, extended forecastle and an improved, and much higher, bridge. The result was a subclass of corvettes dubbed by the RCN Revised Patrols Vessels. These were the navy’s first corvettes specifically designed for open ocean work.

The other factor which complicated the RCN’s attitude towards its corvette fleet in early 1941 was that it simply did not expect to keep them very long. The only concession it made in 1941 to the long-term support of the burgeoning escort fleet on the east coast was the letting of contracts to build nine marine haul-outs ranging in capacity from 200 to 3,000 tons. None of these were ready before late 1942. As Admiral H.G.  DeWolf recalled many years later, the navy made no plans for the long-term maintenance, let alone modernization of its growing fleet of auxiliary vessels. In 1941, the Naval Staff expected the war to last perhaps two more years at most, and then the corvettes would be discarded. On Dec. 7, the Japanese changed the timeline.

What also confounded RCN planning for its burgeoning fleet of corvettes in 1941 was news received in December 1940 that the British were switching to a totally new kind of auxiliary vessel for the anti-submarine war in the North Atlantic, the twin-screw corvette. This was another design to mercantile standards, and therefore one easily built in Canada, and the RCN took an early interest in the design. It was 100 feet longer than a corvette, had a naval bridge, modern weapons and sensors, and a second propulsion plant. It was designed from the outset for work in the broad ocean, with a longer hull specifically tailored to handle the North Atlantic wave interval. It also had a much longer range, more than double that of the original corvette design. When Rear Admiral Percy Nelles heard of the new design, he recommended to the Admiralty that they resurrect the defunct naval term ‘frigate’ to designate the type, and the British agreed. The first British orders for frigates were placed in February 1941.

Under the circumstances, the RCN moved with commendable speed to adopt the frigate for ocean escort duty, but their efforts to get them into service were frustrated by things beyond their control. By April 1941 the RCN had enough information to start exploring frigate construction in Canada, and in May it committed itself to building only these larger vessels as its primary wartime auxiliary ship. Unfortunately, frigates were too long for the locks of the Great Lakes canal system, and so Ontario yards, which were building one-third of the corvette programs, could not be used. There were plenty of yards along the east and west coasts capable of building frigates, but by 1941 they were heavily committed. Yards in the Maritimes were wholly absorbed with refits and repairs, while the long slips in Quebec and British Columbia yards were under contract with the British Ministry of War Transport to build merchant ships.

In fact, the RCN’s plans for new ship construction in 1941 ran smack into a new, massive shipbuilding program for the British worked out by the Canadian government, the British and the Americans. The core of this program was 90 merchant ships to be built in Canada for the British and paid for by the Americans through lend-lease. The Americans were also prepared to pay for warship construction in Canada for the British, and the Canadian government—itself strapped for U.S. dollars—committed its ‘surplus’ productive capacity to meet the need. In 1941, the British Admiralty Technical Mission ordered 10 frigates, 15 of the new Algerine class minesweepers, 15 revised corvettes, and 16 anti-submarine trawlers in Canadian yards. As a result, the British 1941 naval construction program in Canada dwarfed that of the RCN. None of these British contracts could be easily set aside, nor could the British frigate contracts be expropriated for the RCN. The American money that funded them was crucial to Canada’s balance of payments with the U.S. Just as importantly, British expertise in the building of frigates was a welcome boost to Canadian shipbuilders who would ultimately build the same types for the RCN.

So it was not until October 1941 that the first 20 frigates were authorized for the RCN, a figure upgraded in early 1942 to 30. The RCN wanted to have its first 20 in service by March 1943, and had this happened, the story of 1943 might have been significantly different. But despite the intervention of the naval minister in the fall of 1941, and his plea that RCN construction should have precedence over merchant ships, the British program prevailed. The RCN was only promised five frigates by the end of 1943. As naval historian Gilbert Tucker observed, this meant that the first frigates entered Canadian service “three full years after word of the new design reached Naval Service Headquarters, and 21⁄2 years after the first orders had been approved by the Naval Staff.”

Commanding Officer H.G. DeWolf on board HMCS Haida, 1943. [PHOTO: HERB NOTT, LIBRARY AND ARCHIVES CANADA—PA141695]

Commanding Officer H.G. DeWolf on board HMCS Haida, 1943.

As a result, only a handful of RCN corvette contracts were let in Canada in 1941, and no frigates were ordered. The corvettes were simply a spillover of the 16 ships of the 1940 program. There was no “1941” corvette or frigate building program. In fact, the development of the RCN’s fleet stalled in 1941, caught between more corvettes than it thought it needed, an inability to move on quickly to the next class of wartime auxiliary construction, a government committed to balanced books and industrial development, and delays in acquiring the key components of a proper postwar fleet, primarily fleet class destroyers and cruisers.

For these reasons the RCN was also slow to modernize its existing fleet even as it became clear that its fleet of small ships—especially the corvettes—was unsuited for the kind of war it now fought. Although the British had largely abandoned corvette construction by this stage in favour of better designs, they nonetheless modernized their existing corvettes to make them better oceanic escorts. This group included the 10 British-owned, Canadian-built corvettes in Canadian service. By December 1941, HMCS Arrowhead, Bittersweet, Eyebright, Mayflower and Snowberry were in American yards having their forecastles extended and modern radar installed. Unfortunately for the RCN, Canada lacked the infrastructure and equipment to quickly modernize its corvette fleet at home. Nor would the government allow the work to be done in American yards, which would adversely affect Canada’s balance of payments.

The Naval Staff’s solution to this conundrum in early 1942 was to keep the ‘old’ ships steaming and build new ones designed for the new tasks. Although Naval Minister Angus L. MacDonald was opposed to building ‘obsolete’ warships, it was inconceivable that Canadian yards should stand idle as the global crisis deepened. As a result, in early 1942 the government authorized the building of “revised, improved endurance corvettes,” primarily in Ontario yards where the British had placed orders for similar types in 1941. They incorporated years of North Atlantic experience, from improved hull form, a naval bridge, pressurized boiler rooms, modern electronics and sensors, and a dramatically increased operating range as a result of additional fuel storage. In their time, these vessels would give yeoman service, and in early 1942 they were a sensible result of a policy that “every shipbuilding yard should be worked to capacity until we see light ahead.”

But, like the frigates, none of these revised corvettes would enter service for nearly two years. In the meantime, the RCN had to fight an ever expanding war with what it now possessed. If that was not bad enough, the expansion of the war in 1942 worked the Sheep Dog Navy to its limits. It filled in for the Americans in the northwest Atlantic as their destroyers drifted away to the Pacific and eased the burden on the RN, as it too responded to the global war. At a time when the RCN really needed to refit and adapt its fleet to the new demands placed on it, its small escorts were driven to the brink of collapse. The navy understood what it was doing: it knew that the RCN could not win the war. But it could make it possible for others to do so.

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