of these had seen hard war service over the previous six months and the availability rate was low. The recently arrived 90th Bombardment Group was equipped with Consolidated B-24 Liberators, but they too had maintenance problems. There were two medium groups: the 38th Bombardment Group, equipped with B-25 Mitchells, and the 22nd Bombardment Group, equipped with Martin B-26 Marauders, but two of the former's four squadrons had been diverted to the South Pacific Area, and the latter had taken so many losses that it had been withdrawn to Australia to be rebuilt. There was also a light group, the 3rd Attack Group, equipped with a mixture of Douglas A-20 Havocs and B-25 Mitchells. This group was not just short of aircraft; it was critically short of aircrew as well. To make up the numbers the USAAF turned to the RAAF for help. Australian aircrew were assigned to most of the group's aircraft, serving in every role except aircraft commander. In addition to the RAAF aircrew with the USAAF squadrons, there were RAAF units in the Port Moresby area. No. 30 Squadron RAAF, which had arrived in Port Moresby in September 1942, was equipped with the Bristol Beaufighter. Both the aircraft and the squadron proved adept at low level attacks. Also in the Port Moresby area were the 35th and 49th Fighter Groups, both equipped with Bell P-39, Curtiss P-40 Warhawk and Lockheed P-38 Lightning fighters, but only the last were suitable for long range escort missions. Battle Order of battle see Battle of the Bismarck Sea order of battle First attacks The Japanese convoy – comprising eight destroyers and eight troop transports with an escort of approximately 100 fighters – assembled and departed from Simpson Harbour in Rabaul on 28 February. During the January operation, a course was followed that hugged the south coast of New Britain. This had made it easy to provide air cover, but being close to the airfields also made it possible for the Allied Air Forces to attack both the convoy and the airfields at the same time. This time, a route was chosen along the north coast, in the hope that the Allies would be deceived into thinking that the convoy's objective was Madang. Allied air attacks on the convoy at this point would have to fly over New Britain, allowing interdiction from Japanese air bases there, but the final leg of the voyage