The B-26 began to equip the 22nd Bombardment Group at Langley Field, Virginia, in February 1941, replacing the Douglas B-18 Bolo, with a further two groups, the 38th and 28th, beginning to equip with the B-26 by December 1941. Immediately following the Japanese Attack on Pearl Harbor, the 22nd BG was deployed to the South West Pacific, first by ship to Hawaii, then its air echelon flew the planes to Australia. The 22nd BG flew its first combat mission, an attack on Rabaul which required an intermediate stop at Port Moresby, New Guinea, on 5 April 1942.