The Attacker class were a class of escort aircraft carriers in service with the British Royal Navy during the Second World War.
The United States Navy had acquired 22 C3 cargo ships shortly after the Attack on Pearl Harbor to be converted into the . With an increasing need for convoy escorts in the North Atlantic eleven of these were transferred to the Royal Navy, and reclassified as Attacker class, under the terms of the Lend-Lease program.
The ships were originally intended to serve as convoy escort carriers, equipped with both anti-submarine and fighter aircraft, and transport carriers, transferring new and replacement aircraft to forward bases. During successful use during the amphibious invasion of North Africa to cover advancing ground units until land airbases were secured, several ships were refit as strike carriers, equipped with just fighter aircraft. When used as convoy escorts, the ships' aircraft were successful in deterring German submarines from attacking Allied convoys, with a number of German submarines and aircraft destroyed or damaged by the aircraft. Those carriers operating in the strike role took part in two major landings in the Mediterranean and an operation against the in Norwegian waters. Eight of the ships ended the war in the Far East in the campaigns against the Japanese Empire and were then used to transport home prisoners of war.
All eleven ships survived the war and were eventually returned to the United States Navy, which sold eight of them for conversion back into merchant ships. The other three ships were scrapped.
Design and description
After the Attack on Pearl Harbor, the United States Navy acquired 22 C3 merchant ships that were in varying states of construction, to be converted into escort carriers. Eleven of these were transferred to the Royal Navy as the Attacker class, while the 11 retained by the US were named the . They were all laid down in 1941 and 1942, with Ingalls Shipbuilding and Western Pipe & Steel building four each and Seattle-Tacoma Shipbuilding Corporation erecting the additional three, and supplied under the terms of the Lend-Lease program.
The ships had a standard complement of 646 officers and ratings. Crew accommodations were significantly different from the normal for the Royal Navy at the time. Instead of food being prepared by separate messes, it was cooked in the galley and served cafeteria-style in a central dining area. Unlike British-built ships, they were equipped with air conditioning, a modern laundry and a barber shop. The traditional hammocks were replaced by three-tier bunk beds, with 18 to a cabin, which were hinged and could be tied up to provide extra space when not in use.
The ships had a waterline length of with an overall length of . Their beam was at the waterline and a maximum beam of . The draught was at full load and at light load. They displaced at standard load and at full load.
Power was provided by two Foster and Wheeler boilers feeding steam to a General Electric steam turbine engine connected to a single shaft, giving , which could propel the ship at .
All the escort carriers had the capacity for up to 20 anti-submarine or fighter aircraft, which could be a mixture of the British Hawker Sea Hurricane, Supermarine Seafire, and Fairey Swordfish, and the American Grumman Wildcat, Vought F4U Corsair and Grumman Avenger. The exact composition of the embarked squadrons depended upon the mission. Some squadrons were composite squadrons for convoy defence, and would be equipped with anti-submarine and fighter aircraft, while other squadrons working in a strike-carrier role would only be equipped with fighter aircraft. When utilised in ferry service the ships could carry up to 90 aircraft between both the flight and hangar decks. Aircraft facilities consisted of a small combined bridge–flight control on the starboard side above the flight deck that measured . There were nine arresting wires and three barriers at the stern of the ship, along with one hydraulic catapult at the bow which was able to launch a aircraft at . The hangar deck was , which was larger than previous escort carriers, but retained the camber at the bow and stern of the main deck of the merchant ships they were built on. Because the elevators were placed at the ends of the flight deck, pulleys were required for handling planes on and off of the elevators on the hangar deck, which was difficult in normal conditions, and impossible in rough seas.