The Flower-class corvette HMCS Sackville was built by the Saint John Shipbuilding and Drydock Company in Saint John, New Brunswick, Canada. Laid down on 28 May 1940, the ship was launched on 15 May 1941 and commissioned into the Royal Canadian Navy (RCN) on 30 December 1941. Like all Canadian Flower-class corvettes, Sackville was named after a Canadian town (Sackville, New Brunswick) rather than a flower, as in the case of British corvettes. Sackville was one of 294 Flower-class corvettes built for several Allied navies during the Second World War, including 122 built for the RCN. These rugged, inexpensive little ships utilised proven, commercially-available machinery and were simple enough to construct in small Ontario, Quebec, New Brunswick, and British Columbia shipyards lacking any prior naval shipbuilding experience. With the explosive growth of the RCN after 1939, from a small force 3,500 officers and ratings and a fleet of a dozen vessels, the large number of Flower-class corvettes entering service were crewed largely by hostilities-only men of the Royal Canadian Naval Volunteer Reserve (RCNVR) and smaller numbers of men of the Royal Canadian Naval Reserve (RCNR). While the latter were civilian mariners with experience at sea, the RCNVR, by contrast, was composed of men with no prior maritime experience, many of whom were from inland parts of Canada and had never seen the ocean. By 1945, the RCN consisted of over 100,000 officers and ratings and more than 400 vessels, including the 122 corvettes.
HMCS Sackville's wartime service got off to an inauspicious start. After three convoy escort assignments in February and March, the ship's first captain was relieved of command due to poor performance and abusive conduct towards his subordinate officers. This led to the entire ship's company being broken up and reposted to other RCN ships and the trained crew of HMCS Baddeck, under Lieutenant-Commander Alan Easton, RCNR, being posted to Sackville on 6 April. Following workup training, on 15 May 1942, Sackville was assigned to the St John's, Newfoundland-based Escort Group C-3 of the Mid-Ocean Escort Force. Between May 1942 and July 1944, Sackville served with various escort groups of the Mid-Ocean Escort Force, tasked with shepherding merchant vessels across the Atlantic in support of the Allied war effort. These convoys generally comprised around 30 merchant ships, which departed Halifax and other East Coast ports approximately every three days for the hazardous 3,200 kilometre (2,000 mile) journey across the North Atlantic. Over the course of her wartime service, HMCS Sackville escorted 30 convoys comprising a combined 1,200 merchant ships, seeing only 13 ships torpedoed, of which nine were sunk. While the escorts would run down a suspected enemy submarine contact detected by Asdic (sonar), hunting submarines was never the priority and the escort forces' first objective was always the safe and timely arrival of the convoy at its destination. Later in the war, as the number of Allied anti-submarine vessels increased and new technologies and tactics were developed, dedicated groups of highly-trained anti-submarine warships unattached to any convoy would be deployed to hunt down and destroy German submarines.
HMCS Sackville's most notable convoy run was in early August 1942, when escorting the westbound convoy ON 115 between Northern Ireland and Newfoundland. Forming part of Escort Group C-3, Sackville was screening the convoy 400 kilometres (250 miles) east of Newfoundland when on 3 August she came across the German submarine U-43 on the surface. A starshell fired by Sackville forced the submarine to crash dive and the corvette proceeded to drop a pattern of depth charges over its last known position. The blast of the exploding depth charges blew the submarine to the surface briefly before it descended once again and limped back to port in France with heavy damage. The next day, Sackville forced U-704 to break off an attack and dive and, hours later, attacked U-552 on the surface. While an attempt to ram U-552 was unsuccessful, Sackville's 4-inch gun crew scored a hit at the base of the submarine's conning tower and a subsequent depth charge attack caused serious damage to the submarine, forcing U-552 to return to port. Sackville's attacks on these three German submarines played a critical part in allowing the 41 ships of convoy ON 115 to escape with only two losses.
From January to April 1943, HMCS Sackville was refitted in Liverpool, Nova Scotia. The work included the replacement of machinery, the removal of the ship's minesweeping gear, and the extension of the bridge wings to accommodate new Oerlikon 20mm anti-aircraft guns. Later that year, from 19 to 25 September, Sackville was part of Escort Group 9, tasked with escorting the combined convoys ONS 18 and ON 202 from Northern Ireland to Newfoundland. Attacked by a group of German submarines, the convoys suffered seven merchant ships torpedoed, of which six sank, as well as the loss of four escort vessels. Given such heavy losses, Escort Group 9 was disbanded and Sackville reassigned to Escort Group C-2. Interestingly, during the ONS 18/ON 202 engagement, Sackville was rocked by a nearby underwater explosion likely caused when one of the ship's depth charges detonated a German torpedo in the vicinity. The shock of the detonation damaged Sackville's No. 1 boiler, but the corvette remained in service on escort duties until heading to Galveston, Texas for a refit between February and May 1944. This refit involved the aftward extension of Sackville's forecastle in line with the Modified Flower-class design, as well as the fitting of a new bridge and Hedgehog anti-submarine mortar mounting, the relocation of the mast behind the bridge, the replacement of the ship's boats, and the addition of new electronics.
Following the 1944 refit and subsequent workup training in Bermuda, Sackville was assigned to Escort Group C-2 and shepherded convoy HX 297 to Londonderry, Northern Ireland in July 1944. During boiler cleaning in Londonderry, the full extent of the damage to Sackville's No. 1 boiler from the ONS 18/ON 202 action in September 1943 was discovered. When repairs were unsuccessful, No. 1 boiler was removed and Sackville was taken out of front line service. Although initially intended to serve as a training ship at HMCS Kings, an onshore officer training establishment in Halifax, the RCN decided to convert Sackville to a loop layer. The ample empty space where the No. 1 boiler once sat was ideal for storing coils of anti-submarine indicator cables which Sackville would lay across harbour entrances. With a pair of loop-laying cranes installed in place of her 4-inch gun, Sackville served in this capacity until paid off and placed in reserve on 8 April 1946.
While Canada's other Flower-class corvettes were scrapped or sold to foreign navies, Sackville was transferred to Canada's Department of Marine and Fisheries in 1952 and converted into an oceanographic research vessel. Her hull was painted black and all armament removed; in 1964, a laboratory was installed on Sackville's aft superstructure and in 1968 her bridge was enclosed. Sackville served as a research vessel until December 1982 when she was retired and acquired by the Canadian Naval Memorial Trust in October 1983. The Trust had not originally intended to acquire Sackville, instead having planned to acquire the former HMCS Louisburg, which had been sold to the Dominican Republic in 1947 and renamed Juan Alejandro Acosta; however, this vessel and another Dominican corvette, the former HMCS Lachute, were both wrecked by Hurricane David in August 1979, leaving Sackville as the only option for preservation. An extensive renovation project restored Sackville to her 1944 appearance and in 1985 the Government of Canada designated the corvette as Canada's Naval Memorial. In 1988, HMCS Sackville was designated a National Historic Site of Canada on account of her status as the last surviving Flower-class corvette. On 29 June 2010, in conjunction with the Royal Canadian Navy's 100th anniversary International Fleet Review, Queen Elizabeth II and the Duke of Edinburgh visited HMCS Sackville and unveiled a plaque marking her significance as a memorial to those who served and died at sea in service to Canada. The Canadian Naval Memorial Trust continues to operate HMCS Sackville as a museum ship berthed on the Halifax waterfront next to the Maritime Museum of the Atlantic during the spring and summer months. In the winter, Sackville is towed to the nearby Canadian Forces Base Halifax, home of the Royal Canadian Navy's Atlantic Fleet. Every year on the first Sunday in May, Sackville is towed to a location off Halifax's Point Pleasant Park, overlooking the harbour, to participate in ceremonies commemorating the Battle of the Atlantic.
Specifications: HMCS Sackville (K181)
Displacement: 1,170 tons (full load)
Length: 62.5 metres (205 feet 1 inch)
Beam: 10 metres (32 feet 10 inches)
Draught: 3.5 metres (11 feet 6 inches)
Propulsion: 2 x cylindrical Scotch Marine 'fire tube' boilers feeding one four-cylinder vertical triple expansion reciprocating steam engine generating 2,750 horsepower and driving one screw
Maximum speed: 16 knots (30 km/h; 18 mph)Range: 6,437 kilometres (4,000 miles) at 12 knots (22.2 km/h; 13.8 mph)
Armament: 1 x breech-loading 4-inch Mk IV gun; 1 x Quick Firing Mk VIII 2-pounder pom-pom anti-aircraft gun; 2 x 20mm Oerlikon guns; 4 x Mk II depth charge throwers; 2 x depth charge rails with 40 depth charges; 1 x Mk 3 Hedgehog ahead-throwing anti-submarine mortar system
Radar: Type 271 and Type 291
Sonar: Type 127D
Complement: 85 (6 x officers, 10 x Chief and Petty Officers, 69 x sailors)
Below: A visitors' brochure, circa 1990s.
Below: A 2009 visitor's brochure.
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| The sole survivor of 294 Flower-class corvettes built during the Second World War, HMCS Sackville is now a museum ship berthed at a wharf next to the Maritime Museum of the Atlantic in Halifax Harbour. Photograph taken 1 July 2009. |
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| A bow view of HMCS Sackville, showing the ship's relatively wide 10.1 metre (33 foot) beam. This wide beam was an element of the 1930s commercial whale catcher design from which the Flower-class corvette was derived and helped improve stability. Nevertheless, the rough weather and seas in the North Atlantic caused the corvettes to pitch and roll terribly, often leaving sailors seasick and their mess decks awash in seawater. |
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| The restored HMCS Sackville is painted in the 'dazzle' camouflage scheme used by warships on convoy duty in the North Atlantic during the Second World War. Such dazzle camouflage was designed to confuse enemy submarines as to the vessel's actual size, speed, and course. Note the crow's nest on the mast, in which a sailor would be positioned to help spot enemy submarines. Early versions of the Flower-class corvettes were rushed into service and often lacked radar, searchlights, radio telephones, gyro compasses, and even sufficient numbers of binoculars. As such, keeping station with a convoy or spotting enemy submarines and aircraft often relied on visual sighting by lookouts on the bridge and in the crow's nest. |
Photos below taken on 4 July 2009
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| Although built to the original Flower-class design, HMCS Sackville's current configuration reflects the two refits it received in 1943 and 1944. During the first refit, in January 1943, the minesweeping gear was removed and the bridge wings were extended to accommodate 20mm Oerlikon anti-aircraft guns. The second refit, carried out in February-May 1944, saw Sackville's forecastle extended further aft, the installation of a new bridge and Hedgehog mortar mounting, and the relocation of the mast to a position aft of the bridge. The extension of the forecastle to the aft end of the funnel significantly improved the habitability for the ship's company, as well as improved the vessel's stability and speed. |
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| Boarding HMCS Sackville via the gangway. The extended forecastle fitted during the 1944 refit is evident in this photo. The extension provided more enclosed living and working space for the ship's company, protecting them from the harsh conditions in the North Atlantic. |
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| A ceremonial life ring at ship's brow upon boarding. |
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| HMCS Sackville's brass bell, rung to mark the time. Aboard naval vessels, the bell was rung every half hour of a four-hour watch, with the bell rung once at the start of the watch and eight times at the end of the watch. |
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| Looking forward from the port side, abaft the funnel. The ship's Type 271 surface search radar, its radome resembling a lighthouse, towers over the bridge. The Type 271 was the first widely-used naval microwave-frequency radar, capable of detecting a surfaced submarine at approximately 4.8 kilometres (3 miles) and a submarine periscope at 820 metres (2,690 feet). While the British-designed Type 271 radar was introduced in 1941, Sackville and the other Canadian corvettes did not receive 271 sets until later in the war, once the British corvettes had been fitted. |
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| Sackville's wooden name board, with brass lettering. |
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| HMCS Sackville's honours board shows the single battle honour awarded to the ship, for her participation in the Battle of the Atlantic from 1942 to 1944. Between February 1942 and July 1944, Sackville escorted 30 east- and westbound convoys across the Atlantic as part of Escort Groups C-1, C-2, C-3, and 9 of the Mid-Ocean Escort Force (MOEF). |
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| Looking aft from Sackville's bow. The ship's breech-loading 4-inch Mk IX gun is on a raised platform in front of the bridge. The 4-inch Mk IX medium-velocity gun was introduced in 1917 as secondary armament on capital ships; however, the gun is best known as the main armament on the Flower-class corvettes of the Second World War, intended for use against surfaced submarines. The 4-inch Mk IX gun fired a 14.1 kilogram (31 pound) shell to a range of 10 kilometres (6 miles), with a rate of fire of 10-12 rounds per minute. The Mk IX's gun's elevation was between -10 degrees and +30 degrees. As the gun was not linked to the ship's radar and had to be aimed solely on the basis of visual sighting, it was not an accurate weapon, given the pitching and rolling of a corvette in the open ocean. Nevertheless, it could be effective in forcing an enemy submarine to submerge and potentially lose contact with the convoy it was attempting to attack. |
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| The forward-throwing anti-submarine Hedgehog mortar system mounted on the starboard side of Sackville's forecastle, just forward of the bridge. Developed by Britain and introduced on destroyers and corvettes from 1942, the Hedgehog fired up to 24 spigot mortars in a 30 metre (100 foot) diameter circular or elliptical pattern 230 metres (755 feet) ahead of the ship. Given the limitations of contemporary sonar systems, which lost contact as the ship moved over a submerged submarine and thereby provided an opportunity for the submarine to manoeuvre away, Hedgehogs allowed the attacker to maintain contact while firing a spread of mortars. Unlike depth charges the Hedgehogs only detonated on contact with a submarine's hull rather than at a pre-set depth. This made the Hedgehog more deadly than depth charges, which were reliant on causing damage via hydrostatic shockwaves; indeed, one Hedgehog was usually sufficient to sink a submarine. Each Hedgehog mortar weighed about 29.5 kilograms (65 pounds) and carried a 16 kilogram (35 pound) Torpex charge. They were effective to a depth of 400 metres (1,300 feet) and the Hedgehog mounting could be reloaded in about three minutes. Although seawater and spray in the North Atlantic caused technical problems with the Hedgehog's firing circuit and sometimes resulted in an incomplete pattern being fired, statistics compiled at the end of the Second World War demonstrated the success of Hedgehog: on average one out of every five Hedgehog attacks resulted in a kill, compared to fewer than one kill for every 80 attacks using depth charges. |
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| Inside HMCS Sackville's wheelhouse, where the ship's quartermaster steered the ship based on orders communicated from the bridge above via the voice pipes. The ship's wheel is flanked by speed and engine revolution telegraphs, while a compass stands forward of the wheel. |
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| The small Asdic (sonar) hut near the bridge and wheelhouse, where Sackville's Asdic operators would listen for the 'ping' returning from a sonar pulse hitting the hull of an enemy submarine. |
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| The view from Sackville's open bridge. A magnetic compass sits in the binnacle in the centre of the bridge, while various voice pipes lead down to the wheelhouse and Asdic hut. Open bridges, a common feature of British warships of the era, maximised visibility of the surrounding sea and sky but were miserably harsh places to stand a four-hour watch, being exposed to the bitter cold, mountainous seas, driving wind, and salt spray characteristic of the North Atlantic. In an era before electronic navigation aids, the corvettes often relied entirely on the magnetic compass and a sextant for celestial navigation to make their way across the Atlantic during convoy runs. In addition to the ever present threat from submarines, the inexperience of the Royal Canadian Navy Volunteer Reserve (RCNVR) sailors comprising the bulk of corvette crews meant that the captain spent most of his time on the bridge, taking brief naps in a cot in the wheelhouse below when able to do so. |
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| The 20mm Oerlikon gun on the starboard bridge wing. Designed by the Oerlikon company of Switzerland and introduced in 1939, this variant of the 20mm gun could fire 250-320 rounds of high explosive or semi-armour piercing ammunition per minute, with a range of 3-4 kilometres (1.9-2.5 miles). Although designed as an anti-aircraft gun, it was also used to attack nearby surfaced enemy submarines, both to compromise the watertight integrity of the submarine's hull and conning tower and to suppress enemy submariners attempting to man their vessel's deck gun. Sackville, like other early built Canadian Flower-class corvettes, was originally fitted with First World War vintage Lewis .303 machine guns firing small bullets incapable of penetrating the hull of a submarine. These were replaced on Sackville by the far more powerful 20mm Oerlikon guns in two single mounts during the January 1943 refit. |
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| Looking aft from the port bridge wing. HMCS Sackville's funnel sports a green maple leaf badge and the distinctive red-and-white 'barber pole' design that was adopted by the Royal Canadian Navy's Escort Group C-3 of the Mid-Ocean Escort Force in early June 1942. The barber pole insignia continues to be used by the Royal Canadian Navy to the present day, being painted on the funnels of all ships of the RCN's Atlantic Fleet, based at Halifax. The green maple leaf badge on the funnels of Canadian warships began informally during the Second World War and was formalised via a naval order in September 1944. In the post-war period, the green colour was switched to red for better contrast and a red maple leaf continues to be used on each side of the funnels of Canadian warships to this day. |
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| Looking forward along the starboard side of HMCS Sackville's upper deck. The two starboard Mk II depth charge throwers, each containing a depth charge, are visible, with spare charges stored on deck nearby. Sackville was fitted with a pair of Mk II depth charge throwers on each side, plus two sets of depth charge rails over the stern. The ship carried 40 depth charges, steel cylinders filled with 136 kilograms (300 pounds) of TNT and a pistol primer set to detonate the charge at a pre-set depth based on water pressure. With the firing of a cordite charge in the thrower, the depth charge was thrown 45 metres (150 feet) out from the ship's side. A typical pattern of 6-10 depth charges were fired during an attack on a suspected submarine. A drawback in the use of depth charges was that the attacking ship lost contact with the submarine as it sailed over the submarine's suspected position; and when the depth charges detonated, the disturbed water they created blinded the ship's sonar for up to 15 minutes, allowing time for a surviving submarine to escape undetected. Later in the war, as more anti-submarine vessels became available to the Allies, depth charge attacks were conducted by two or more vessels, with one standing off to maintain sonar contact while the others conducted methodical depth charging runs over the location of the submarine. |
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| A view forward along the starboard passageway inside Sackville's forecastle. The sailors' mess deck is at the forward end. |
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| The galley, in which meals were prepared. On a rotating basis, one man from each mess (4-8 men) would come to the galley to collect the food and bring it back to the mess decks to be eaten. |
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| The forward mess deck is now used to house displays on HMCS Sackville and her ship's company, with parts recreated to show how the sailors lived aboard. On the deckhead can be seen the black rails from which sailors slung their hammocks 18 inches apart. A hatch leads down to another mess deck below. On the right of the photo is a rack in which hammocks would be rolled up and stored when not in use. |
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| A display showing the mess deck as it would have looked during the war, with hammocks slung from the deckhead, wet clothing hanging on lines, and off duty sailors eating their meals at mess tables. Although a Flower-class corvette's crew was originally planned as four officers and 48 ratings, as more weapons and equipment were fitted to the ships and as convoy distances grew longer, the crew size increased, eventually reaching 85 or more. Such a crew size strained the limited accommodation space available in the small corvettes. |
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| Another scene of mess deck life. Sailors mend clothing, read, enjoy a meal, or relax with card games and cribbage. In rough seas, the ship would be pitching and rolling badly, causing seasickness, while seawater sloshed around the deck and condensation dripped from the deckheads. |
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| The captain's cabin, equipped with a bunk, desk, and sink. When at sea, the captain was usually on the bridge and rarely had the opportunity of a good night's sleep in his cabin. At the beginning of the war, a corvette's captain was usually a Lieutenant Commander or Lieutenant in the Royal Canadian Naval Reserve (RCNR), supported by RCNR officers who were deck officers or engineers on merchant ships in peacetime. However, as the number of new warships coming out of the shipyards increased and the need for crews soared, command of many new corvettes was given to officers of the Royal Canadian Navy Volunteer Reserve (RCNVR), comprising men with no experience at sea and often from inland parts of the nation who had joined the RCNVR for the duration of hostilities only. |
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| Looking down into the engine room, dominated by the four-cylinder triple-expansion reciprocating steam engine that generated 2,750 horsepower and drove Sackville at a top speed of 16 knots (30 km/h; 18 mph). Reciprocating steam engines were old technology by the Second World War, but they were reliable, economical, and within the ability of Canadian industry to manufacture, unlike the modern, complex steam turbine engines installed on larger warships. Reciprocating steam engines were also easier for newly-recruited RCNVR personnel with no prior maritime experience to learn to operate and maintain. The engine was fed by steam generated in two Scotch Marine 'fire tube' boilers in two separate boiler rooms forward of the engine room; Sackville's No. 1 boiler was damaged in a convoy battle in September 1943 and removed in 1944. The boiler rooms and engine room together consumed fully one-third of the space in the hull aboard a Flower-class corvette. |
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| A view over the stern of HMCS Sackville. A pair of depth charge rails were used to roll charges over the stern during an attack on a suspected submarine. The blue-topped cylinders atop the depth charge rails on the right are smoke floats that could be released from the ship to emit a thick, white, chemically-generated smoke screen to conceal a convoy from attacking enemy vessels or aircraft. The corvette could also generate a black smoke screen by injecting oil into its funnel or restricting air supply to the ship's boilers in order to cause incomplete fuel combustion and consequent smoke. |
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| The White Ensign, the flag of the Royal Canadian Navy between 1911 and 1965, flies from HMCS Sackville's stern ensign staff. |
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| A final view of HMCS Sackville, sole survivor of the 294 Flower-class corvettes built during the Second World War and now berthed on the Halifax waterfront as a museum ship and Canada's Naval Memorial. |
