World War II: The aircraft carrier HMS Ark Royal sinks due to torpedo damage from the German submarine U-81 sustained on November 13.

An aircraft carrier is a warship designed to carry, launch, recover and support aircraft at sea, equipped with a full-length flight deck and hangar facilities that allow it to serve as a mobile, seagoing airbase. Typically it is the capital ship of a fleet, as it allows a naval force to project seaborne air power far from national territory without depending on local airfields for the staging of aircraft operations. Since their inception in the early 20th century, aircraft carriers have evolved from wooden vessels used to deploy individual tethered reconnaissance balloons, to nuclear-powered supercarriers that carry dozens of fighters, strike aircraft, military helicopters, AEW&Cs and other types of aircraft such as UCAVs. While heavier fixed-wing aircraft such as airlifters, gunships and bombers have been launched from aircraft carriers, these aircraft do not often land on a carrier due to flight deck limitations.