Why did US aircraft production increase sharply between 1941 and 1942?

US aircraft production increased sharply between 1941 and 1942 primarily due to the escalating demands of World War II following the attack on Pearl Harbor in December 1941. The U.S. government mobilized its industrial capabilities through initiatives like the War Production Board, which prioritized military output. Additionally, the expansion of factories and the introduction of new production techniques, such as assembly lines, significantly boosted efficiency and output. This surge was crucial to supply both American forces and allied nations in the fight against Axis powers.