The squadron was constituted on 17 August 1943 as the 423d Night Fighter Squadron at Orlando Army Air Base, Florida, however it wasn't organized until 1 October. The 423d was the second squadron of the third group of dedicated night fighter squadrons trained by the Army Air Forces. It initially trained with the Douglas P-70 Havoc night fighter at Orlando, although later that fall the squadron began to train with the Northrop YP-61 Black Widow.Neither Maurer nor Robertson indicate the squadron ever flew the P-61. Robertson, Maurer, Combat Squadrons pp. 355–356. In January, training was interrupted when the night fighter school moved from Florida to Hammer Field, California. After the relocation, the squadron completed its training in March 1944.Pape, Campbell & Campbell,
