During the thick of the fighting of World War 2 (1939-1945), British authorities and local industry looked to strengthen naval strength in the region, resulting in the authorization a new light-class aircraft carrier that could be built at civilian shipyards at-speed. These came to be know by the encompassing name of "1942 Design Light Fleet Carrier". They were dimensionally smaller than true, frontline Royal Navy (RN) types but ore capable than escort carrier designs - while carrying a healthy complement of combat aircraft into battle.
The Road to the Bonaventure
The Colossus-class was drawn up for this very requirement and the group was planned to number sixteen total warships. However, eight were completed to the design standard and a further two of the class existed as "maintenance carriers" for their part. Another five ships were committed to the related Majestic-class. Not all were made available before the end of the war arrived in 1945.
HMS Powerful was the sixth of six Majestic-class ships and constructed by the specialists at Harland & Wolff. her keel was laid down on November 27th, 1943 and the vessel was launched (partially completed) on February 27th, 1945 as the war in Europe and the Pacific was still being decided (ending in May 1945 and September 1945, respectively).
With the end of the war, there was no desperate need to add any more costly warships to the British stable so construction on Powerful was suspended for the foreseeable future. She lay in this state until work was restarted in 1952 after her incomplete hulk was secured by the Royal Canadian Navy (RCN) to operate under the new name of "HMCS Bonaventure" (selected, on the basis of cost, to succeed HMCS Magnificent in same role). Before she was commissioned for service with the RCN, her design was largely revised to a new fighting standard, one intended to combat the new threat in the East - the Soviet Union.
HMCS Bonaventure Walk-Around
Changes to Powerful included an all-new, modern island superstructure with American radar fitted to a lattice-style mast work. Equally-modern jet-powered fighter aircraft would be launched from her deck by way of a steam catapult and recovery via arrestor wire. Launching was aided by a new 8-degree angled section of deck over the forecastle/bow. Landing would be aided by a stabilized mirror-based landing sighting system. As enemy aircraft remained a primary threat to surface ships, local defense would be handled by 3" (76mm) Anti-Aircraft (AA) guns set in four twin-gunned mountings positioned along the sides of the upper hull for maximum protection. Beyond this, any accompanying ships and submarines would be used to protect the vessel.
Her initial aircraft inventory included the American McDonnell F2H "Banshee" jet-powered fighter also being employed by the United States Navy (USN). This twin-engine jet was only exported to Canada and total production of all marks ended at 895 units before the end. The last flew under the RCN flag in September of 1962.
Onboard systems included the AN/SPS-10 series surface-search radar along with the AN/SPS-12 air-search radar fit. The crew numbered 1,200 under standard operating conditions but this could be pressed to become 1,370 under wartime conditions as needed. Power was from 4 x Admiralty 3-drum type boiler units feeding Parsons single-reduction geared steam turbines outputting 40,000 horsepower to 2 x Shafts astern. Maximum speed in ideal conditions could reach beyond 24 knots. Dimensions included an overall length of 630 feet, a beam of 112.5 feet, and a draught of 24.5 feet. Displacement reached 16,300 tons under normal load and up to 20,320 tons under full load.
Her overall arrangement was traditional with the island superstructure set to starboard side, though positioned slightly ahead of midships. The remained of the exposed surface space was used for the flight deck which incorporated a hangar elevator between midships and the stern.
The reborn Powerful - now HMCS Bonaventure - was commissioned on January 17th, 1957 under the fighting motto of "Not For Us Alone" and assigned Halifax, Nova Scotia as her homeport. Up to sixteen Banshee fighters (F2H-3 production models) initially made up her direct-contact air arm but these were only fielded as such until 1961-1962 - at which point the air arm converted to an all Anti-Submarine Warfare (ASW) role consisting of fixed-wing and rotary-wing aircraft types. Included in the carrier's inventory were Grumman CS2F "Tracker" aircraft (added in 1959) and HO4S-3 "Whirlwind" helicopters, both equipped with ASW gear. With the loss of the Banshee force, this inventory became eight Trackers and thirteen Whirlwinds. In time, the Whirlwinds were succeeded by the Sikorsky CHSS-2 "Sea King" helicopter in same role. This resulted in modifications to the ship in 1963 to accept the new helicopters.
The vessel conducted various voyages and NATO-related exercises for her time at sea (including forming part of the allied Western force during the "Cuban Missile Crisis" (October 1962). From 1966 until 1967, the warship was given her final major refit and this consisted of upgraded the old American radar system to that of Dutch design. Two of the forward AA gun emplacements were deleted for better balance at-sea and the mirror landing aid was switched to a Fresnel system. Internally, various sections were improved regarding aircraft management and radiation protection (nuclear war was a very real and major threat of the Cold War period).
The End of the Line
By the end of the 1960s, HMCS Bonaventure was labeled expendable amidst Canadian defense cuts and selected for decommissioning. She accepted her last aircraft landing action in December of 1969 and transported troops for training to Jamaica the following January. She was finally paid off in 1970 and decommissioned on July 3rd of that year - ending her time at sea. Her stripped hulk was sold for scrapping and she was finally broken up in 1971 (in Taiwan) - with just a few of her components saved for posterity (for instance one of her anchors is displayed outdoors at Point Pleasant Park in Halifax, Nova Scotia).
Over the course of her ocean-going career, HMCS Bonaventure was assigned three different hull identifiers: RML-22, RRSM-22, and CVL-22, mainly due to her changing role for the RCN.