3CCW - Royal Canadian Navy Aircraft Carriers (and Related 'Flat-Tops')
Aircraft carriers were key tools for projecting British power. As such, carriers allowed Britain to secure connections with a far-flung Commonwealth and the remnants of Empire. Carriers were also intended to enable Britain is quick response to global crises. However, in a more Euro-centric BETA context, carriers were largely reduced to being components of the mid-Atlantic anti-submarine warfare and convoy escort roles.
Canada's strategic considerations were rather different - being focused on ASW (by agreement with the Royal Navy) and securing North Atlantic supply routes - in both directions. These roles had been largely inherited from RCN wartime experience but now with a much-reduced fleet. A key difference which emerged in 1950 was the need to maintain a truly two-ocean navy. Until early-1945, the Pacific had been largely ignored by RCN planners. Although a 'pivot' was being made before the Summer of 1945, the surrender of Japan eliminated any urgency. This changed dramatically in 1949-50 with a new requirement for the RCN to help secure trade routes between Canada and the Antipodes.
RCN Light Fleet Carriers (RLF)
With the RCN's roles of ASW and escort, DND planners concluded that Canada required no aircraft carriers larger than its Light Fleet Carriers (RLF). Three classes of Light Fleet Carriers served - RLF (I) Colossus class; RLF (II) Majestic class; and RLF (III) Warrior class. Of these, two of the Pacific-based Colossus class carriers would be rebuilt as angled-deck RLF (IA)s in the mid-1950s - bringing them more in line with the east coast Majestics. By 1974, the rebuilt and upgraded RLF (IA) Colossus and RLF (II) Majestics had been completed replaced by new RLF (III)s.
With the cancellation of the planned 'Warrior-B' class in 1976, it became necessary to return RLF (IA) HMCS Lansdowne and RLF (II) HMCS Bonaventure to service as training vessels. Since these now-ancient ships still had 'steamer' powerplants, useful training was largely restricted to actual carrier operations (including aircraft launch and retrieval). The four RLF (III) Warrior-A would be ceaselessly-updated. In the early-to-mid-1980s, the Warrior-As would go through a major MLU which brought them up to the standard of the cancelled Warrior-B class carriers. In this updated form, the Warrior-A would serve on past the end of the Cold War.
Over time, the escort role came to dominate for the Warrior-As. ASW sensor-equipped helicopters were briefly eclipsed by tilt-wing ASW - however, the Canadair CL-84N Kingfishers were quickly withdrawn from the ASW role. Stripped of their ASW gear, the Kingfishers became RLF Carrier Replenishment At-Sea transport aircraft. Once the aged fixed-wing ASW aircraft disembarked, aerial roles for the Warrior-As were restricted to fleet top-cover, intercept, and strike.
RCN Helicopter Carriers and other Ad Hockery
The Warrior-A roles could shift because to the advent of Helicopter Escort Carriers (REH). These lighter Yukon class ships were to herald the era of all gas-turbine propulsion for frontline RCN warships. This, along with rather slender lines, made the REH the fastest 'flat tops' in the Canadian fleet. Ironically, the basic design had been inspired by one of the slowest carrier classes - the Carrier, Light Helicopter (RLH) aka 'Pincher class'. These were rebuilds of the RCN's ancient Carriers, Light Escort (RLE) which, in turn, were conversions of WW2-era Victory freighters.
The RLEs were updates of the crude, wartime Merchant Aircraft Carrier concept. These 'flat tops' provided direct air cover of a sort for convoys on the trans-Pacific run. These ships also inspired a less elegant solution - the gawky Carriers, Bulk, Volunteer Reserve (RBVR). These ships held containered Canadian grain below decks but could launch light patrol aircraft from their wooden flight decks. Perhaps fortunately, neither of these 'ultralight' carrier concepts was ever tested in battle. As it turned out, rotary-wing operations were a natural from such vessels - eventually displacing onboard fixed-wing aircraft altogether.
Operationally, the conversion of RLEs from conventional, fixed-wing carriers into Carriers, Light Helicopter (RLH) was a great leap forward. The RBVRs would then follow suit - in a limited way, with light helicopters - as the Carriers, Bulk, Helicopter (RBH). The two conversions were unofficially known as the 'Improved Khorason class'. Equally unofficially, the two follow-on RBHs would be known as the 'Durum' class. The RBH fleet was reduced back to two hulls by 1980 - by that stage, hybrid wheat production in the Antipodes had increased to the point that Canadian bulk imports were no longer as essential to the region. Ex-CVR Khorasan would be sold for re-conversion as a civilian bulk carrier. Ex-CVR Prairieland would be transferred to the South African Navy - as HMSAS Seksern (R01). [2]
An Icy Experiment
Less successful was the Ice-Protected Transport Carrier (RPT) concept. The Resolute class was another 'flat top' - this time, built atop an ice-protected bulk-carrier transport ship. It was quickly realised that the expertise of the Canadian Coast Guard's ice service would be needed (resulting in mixed crewing). The sole RCN RPT, HMCS Resolute Bay (RPT770), operated for only four seasons before being transferred to the Coast Guard in 1962 - joining her sister-ship CCGS Arctic Bay (RPT771). Both ships would later be replaced by the Coast Guard's more practical Tuktoyaktuk class Arctic Re-Supply Vessels. The RPT would be the RCN's last foray into ice-protected vessels. Henceforth, it would the role of CCG surface vessels to secure the High Arctic.
________________________________________
[1] The CRAS (Carrier Replenishment At-Sea) transport role was equivalent to US Navy COD or Soviet Red Fleet TSSA (transportnyy samolet snabzheniya avianostsa)
[2] Although coded 'R' for an aircraft carrier/vliegdekskip, the South Africans classified the HMSAS Seksern as an HDOS (Helikopter draer opleiding-skip or Helicopter Carrier Training Ship). She was later reclassed as a RSAN accommodation ship moored first in Durban Harbour, then in Richards Bay.
