WWII: strength and losses of U.S. and Japanese aircraft carriers 1941-1945

The Second World War marked an important development in the history of naval warfare, as it was the time when the aircraft carrier replaced the battleship as the central vessel of the modern navy. Aerial warfare had already emerged in the First World War, but its potential at sea had not yet been realized - the attack on Pearl Harbor was an example of just how destructive air raids from the sea could be, but it was not until the battles of 1942 where the aircraft carrier cemented its position as the most important military vessel. In the war's early years, the Japanese Navy had the numerical advantage over the United States, but U.S. production would then see this balance shift in the Allies' favor in 1943.

Japan loses its advantage

When the U.S. joined the war in late-1941, Japan had already been at war in the Pacific theater for roughly 4.5 years, and had 11 aircraft carriers in its navy - in contrast, the U.S. navy had seven aircraft carriers in its possession, split between the Pacific and Atlantic. When both navies clashed in mid-1942, Japan lost one carrier in the Battle of the Coral Sea, before the U.S. sunk four at the Battle of Midway at the expense of just one - other U.S. carrier losses were in smaller battles skirmishes.

The U.S. steams ahead

In 1943, U.S. naval production was at its highest level in the war, and this year's output alone exceeded the total wartime output of all other major powers combined. The Allied counteroffensive against Japan was disrupting its ability to reinforce its Navy, and heavy losses in the previous two years meant that Japan had also lost a large number of its most skilled pilots and engineers. The Imperial Japanese Navy never truly recovered from Midway, and would possess a total of 18 aircraft carriers throughout the war, but 14 of these were ultimately lost - the majority of which fell around the Philippines, with three sunk during the Battle of the Philippine Sea. The U.S. lost just one aircraft carrier after 1942, at the Battle of Leyte Gulf, and it would finish the war with 29 aircraft carriers in its navy, compared to just four for the Japanese.