On April 29th 1944 the American Task Force 58 launched their second major attack on Truk Lagoon. Although there had been a number of land based B-24 bombing runs on Truk from Rabaul the Japanese had managed to bring in a number of reinforcements. The Americans believed that taking the Lagoon would be too difficult by direct amphibious assault so the idea was to neutralize the Japanese forces based in Truk and move on to more important targets elsewhere in the Pacific. It was important that Japanese air support was crushed as planes operating from Truk could become a thorn in the Americans side and also provide aircraft reinforcements in other engagements in the region.
Unlike the first attack in February the Japanese were ready and waiting for the second American attack and although they managed to put up some initial resistance the Japanese were soon overrun. Shipping was not the focus of the second attack which concentrated on destroying the land and air facilities in the Lagoon. No major vessels were sunk in this attack as large vessels had abandoned calling at Truk however approximately another 20 vessels of various sizes were sunk during the raid.
In all the Americans made 2,200 sorties against Truk and dropped 785 tons of explosives causing enough damage to ensure that Truk played no major part in the war.