CVE-9 Bogue

During the early days of WW2 the need for air cover for convoys was made clear, since the heaviest losses to U-boats was in the mid-Atlantic, where land-based air was unable to reach. Using merchant ship hulls and adding a rudimentary hangar and flight deck, escort carriers became one of the weapons responsible for defeating the U-boats. The first of the escort carriers was the British HMS Audacity, soon followed by the Japanese Unyo class and the US Long Island.

In April and May 1941 the Royal Navy ordered six American C-3 hulls for conversion to escort carriers. Unlike previous ships which were diesel-driven, one of these conversions, HMS Tracker, featured a steam-turbine plant. Tracker made 18.5 sustained knots at sea, two knots faster than the US CVE-1 Long Island by two knots. Tracker had a through-going hangar, and a wider flight deck than the Long Island. The Tracker design formed the basis for the American Bogue class.

A total of eleven CVE-9 Bogue-class ships were commissioned in the US Navy, and though most were transfered to the Royal Navy. Bogue was originally classified AVG-9, but was changed to ACV-9, 20 August 1942; CVE-9, 15 July 1943; and CVHE-9, 12 June 1955.

The C-3 merchant ship conversion, on hulls that could be quickly built, provided only the most basic aviation facilities. But the crude installation of the aft elevator made aircraft handling difficult. The ships had only one screw, a disadvantage in handling damage. And they were not well suited for aircraft handling, since the hangars followed the sheer and camber of the original merchant ship deck.

The original battery for this class specified 2 5" L/51 guns, plus four quadruple 1,1" guns, which would be comparatively easy to come by since they were being removed from front-line warships.

All ships had their initial outfit of 5" L/51 guns replaced by L/38 guns, later ships were completed with them. The final anti-aircraft fit comprised sixteen 40mm L/56 and twenty 20mm L/70, but not all ships were outfitted. Radar equipment added included SC air-search radar, combined with high-frequency / direction-finding antennae. In mid-1945, modernizations comprising the use of modern fire-direction equipment and additional 40mm guns were contemplated, but not applied to all units.