The two veteran squadrons engaged in a series of large strikes mounted by Fifth Air Force against Rabaul in the latter half of October, attempting to neutralize the Japanese base before Allied landings on Bougainville, scheduled for 1 November. On 2 November, the 71st and 405th BS were part of a force of nine understrength squadrons of B-25s and six squadrons of P-38 Lightning fighters that attacked Simpson Harbor to cover the landings. In its strafing attack on shipping, the 38th lost three B-25s to antiaircraft fire from numerous Japanese naval vessels in the harbor.