ST. LAURENT Class
(DDH) destroyer escort
|ST. LAURENT Class|
These ships were the first major warships designed and built in Canada. They were some of the very first new designs to appear after the Second World War, and were among the most sophisticated. Known as 'Cadillacs', they had relatively luxurious crew accomodations. They were similar to the RN's contemporary WHITBY (Type 12) frigates, but relied more on American equipment than British.
Designed to operate in harsh Canadian conditions, these ships looked remarkably different from other warships of the time. They were built to counter NBC (Nuclear, Biological, and Chemical) conditions, which led to their rounded hull, continuous maindeck, and the addition of a prewetting system to wash away fallout and other contaminants. In addition, the living spaces of the ship were part of a 'citadel' which could be sealed against contamination for the safety of the crew. Other inovations included an operations room (CCR, or CIC in USN parlance) seperate from the bridge from which the captain could command the ship while in combat, 12 seperate internal telephone systems, air conditioning, and various other systems.
Built with the latest in radar and sonar systems, they were well-equiped to detect the presence of air, surface, and submarine targets. These sensors directed modern guns and ASW weaponry. The FMC 3"/50 Mk.33 was primarily an anti-aircraft weapon, of minimal use with surface targets. It was guided by fire control radars mounted right on the gun. The twin 3" gun mounts were open to the weather when the ships were first built, but fibreglass enclosures were later added. It remained in service with the Canadian Navy until 1998. Four ships of the class were also fitted with single 40mm Bofors mounts aft of the bridge, but these were later removed. Her ASW weapons included Y-gun launched homing torpedoes and two British triple-barrelled Mk.10 Limbo mortars, which launched projectiles forward and to the side of the ship.
With the advent of the nuclear submarine, however, it became apparent that even more efficient detection of submarines was needed to find submarines at greater distances than possible at the time. It was decided then to modernize the ships of the ST. LAURENT class to carry helicopters and the new SQR 504 Variable Depth Sonar (VDS). As a result, in the early 1960's all seven ships of this class were converted into helicopter carrying destroyers (DDH). In June of 1963, HMCS ASSINIBOINE was recommissioned after this conversion. This involved the removal of one of the Limbo ASW mortars and the aft 3"/50 gun to make room for the hangar and landing deck, the twinning of the single funnel, and various other improvements all over the ship. Activated fin stabilizers were added to reduce the ship's roll in heavy seas, as well as the Beartrap device which allows helicopter recovery in almost any sea state. One CH 124 Sea King helicopter was carried. The transom was altered drastically in order to allow for the placement of the new Canadian designed SQS 504 VDS. The VDS was instrumental in extending the range of the ship's sonar, then limited to about 2000 yards, and was in essence a complete sonar set that could be lowered by cable to great depths behind the ship.
In the late 1970's and early 1980's, the 6 newest members of the class underwent a refit intended to extend the service lives of the ships, called the DEstroyer Life EXtension program (DELEX). The ships were initially intended for only 25 years of operation, and it had become apparent that they would not be replaced until they were nearing 35 to 40 years of service. For the ST. LAURENT class, DELEX meant that the electronics for both radars were upgraded with solid state replacements and hull and machinery repairs were undertaken so as to allow safe operation for up to another 15 years.
The ST. LAURENT class served as the basis for another 11 ships, in two different classes, whose design differed only slightly. All were named after Canadian rivers, though many shared names with Second World War destroyers.
ST. LAURENT herself, however, paid off early in the 1970s during the RCN's manpower shortages. Differing slightly from her sisters in her machinery, she never returned to service or underwent the DELEX refit, and was towed away for scrap in 1980. During her tow to Texas, she passed through the tail end of a hurricane, and sank after taking on water.
Between October of 1981 and May of 1982, FRASER underwent her
DELEX refit, and partly became a test ship for new equipment. In 1986
fitted with the SQR 19 towed array sonar as well as new towed array
processors as part of the ETASS program. This combination of sonar
are now fitted to the new HALIFAX class frigates as the CANadian Towed
Sonar System (CANTASS). In 1987, she tested the SLQ 25 Nixie towed
decoy, which was also fitted to the HALIFAX class ships as well as
of the IROQUOIS and ANNAPOLIS classes. Also tested was the URN-20A
(Tactical AirCraft Navigation) beacon, which was mounted on a large
lattice mast between the funnels. In 1988 and through to 1989, she was
first ship to operate a HELTAS (Helicopter Towed Array Sonar) Sea King
helicopter later crashed, and was not replaced). On October 5, 1994,
made her final sailpast in Halifax after steaming over 900,000 miles
her career. She was the last ST. LAURENT class destroyer to leave
FRASER was purchased in 1997 by the Nova Scotia Artificial Reef Society
(the same group which sank SAGUENAY outside Lunenburg Harbour), to be
into a museum alongside in Bridgewater, NS. To date (2005), she is
not open to the public.
(click on thumbnail for bigger image)
Barrie, Ron and Macpherson, Ken. (1996). Cadillac of
Destroyers: HMCS ST. LAURENT and Her Successors.
Steed, Roger G. (1999). Canadian Warships Since 1956. Vanwell Publishing Ltd. St. Catherines, ON.
Jane's Fighting Ships, Various Editions
Conway's All The World's Fighting Ships, Various Editions
With information from the files of Mike Potter.
ASDIC, RADAR, and IFF
Systems Aboard HMCS HAIDA website by Jerry Proc.
Correspondence with M. Healey.
Back to the Canadian Navy - Postwar Fleet