The escort aircraft carrier, was a small and slow type of aircraft carrier.
The escort aircraft carrier or escort carrier, also called a "jeep carrier" or "baby flattop" in the USN or "Woolworth Carrier" by the Royal Navy, was a small and slow type of aircraft carrier used by the British Royal Navy (RN), the Imperial Japanese Navy and Imperial Japanese Army Air Force, and the United States Navy (USN) in World War II. They were typically half the length and one-third the displacement of the larger fleet carriers. While they were slower, less armed and armored, and carried fewer planes, they were less expensive and could be built in less time. This was their principal advantage, as escort carriers could be completed in greater numbers as a stop-gap when fleet carriers were scarce. However, the lack of protection made escort carriers particularly vulnerable and several were sunk with great loss of life. The light carrier (hull classification symbol CVL) was a similar concept to escort carriers in most respects, however they were intended for higher speeds to be deployed alongside fleet carriers.
Escort carriers were too slow to keep up with the main forces consisting of fleet carriers, battleships, and cruisers. Instead, they were used to defend convoys from enemy threats such as submarines and planes. In the invasions of mainland Europe and Pacific islands, escort carriers provided air support to ground forces during amphibious operations. Escort carriers also served as backup aircraft transports for fleet carriers, and ferried aircraft of all military services to points of delivery.In the Atlantic, the escort carriers were used to protect convoys against U-boats. Initially escort carriers accompanied the merchant ships and fended off attacks from aircraft and submarines. Later in the war, escort carriers centered hunter-killer groups which sought out submarines instead of being attached to a particular convoy.
During the Leyte Campaign, at the Battle off Samar, the Japanese Center Force of cruisers and battleships, including Yamato, the largest battleship ever built met the US task force of escort carriers and destroyers known as "Taffy 3". The escort carriers and destroyers were not expected to put up much of a fight against major big-gun warships. Nonetheless, the Japanese were turned back by furious defence put up by "Taffy 3", with the Wildcat and Avenger planes playing a key role against the Japanese who had no air cover, as well as the US destroyers who made torpedo runs. The US sunk three Japanese cruisers in that engagement, at the cost of one escort carrier and three destroyers.Of the 151 aircraft carriers built in the United States during WWII, 122 were escort carriers. Though no examples survive to this day, the Casablanca class holds the distinction of being the most numerous single class of aircraft carrier ever built, with 50 having been launched. The Bogue class escort carrier comes in a close second, with 45 launched.