finally commenced on the night of October 25–26, but the attacks on Henderson field were repulsed by the Marines with heavy losses. Santa Cruz Concurrently with the Army's offensive on Guadalcanal, the IJN planned their largest naval operation to date in order to counter and defeat any American naval forces operating in support of the Marines on Guadalcanal. The Combined Fleet departed Truk on October 11 with a force of four battleships, four carriers, nine cruisers, and 25 destroyers. In addition, the Eighth Fleet in Rabual contributed four more cruisers and 16 destroyers. On October 25, Yamamoto ordered the Combined Fleet to engage the Americans. Just after midnight on the night of 25–26 October, an American PBY patrol aircraft located the Japanese fleet. Finding the Japanese force just before dawn, two SBDs dive-bombers from the Enterprise attacked the and scored a pair of hits that damaged the flight deck, consequently starting numerous fires onboard the carrier. However, the Japanese had already launched a sixty-five aircraft strike against the American task force. Through a ring of antiaircraft fire and the carriers fighter cover, the Japanese dive and torpedo bombers registered a number of hits on the . By 9.30 am the carrier was dead in the water, but planes from the Hornet had also located the Japanese and six bombs struck the deck of the Shōkaku, removing her from the battle. Some Hornet SBSs attacked the heavy cruiser , damaging her so severely that she was forced to return to the port at Truk. The Battle of Santa Cruz was the fourth carrier clash of the war. The Japanese managed to sink the carrier Hornet , damaged the Enterprise, a battleship, a cruiser, and a destroyer. Yamamoto ordered his subordinates to seek a night battle to finish off the fleeing Americans, but their fuel situation forced them to return to Truk by October 30. Although American losses had been high, the Japanese had been turned back. Two Japanese carriers were heavily damaged and carrier air groups had also been decimated with the greatest single loss of carrier aircrews to date, 148 aviators. These losses prevented the Japanese from exploiting their success. Failure to take Guadalcanal The battle for Guadalcanal reached a crescendo in November. After the victory at Santa Cruz, the Japanese were sure that the naval balance in the south Pacific had swung in their favor. They planned a more