Amphibious Corps, commanded by Major General Alexander Vandegrift, victor of the land campaign on Guadalcanal. Vandegrift's force, a total of 14,321 men, consisted of the 3rd Marine Division (reinforced), under Maj. Gen. Allen H. Turnage, the U.S. Army's 37th Infantry Division, under Maj. Gen. Robert S. Beightler, and the Advance Naval Base Unit No. 7. Landings at Cape Torokina First day: 1–2 November 1943 Three groups of transports converged in Empress Augusta Bay on the morning of 1 November. The existing maps of the Bougainville coast that the Allies possessed were highly unreliable German Admiralty charts from about 1890. A few corrections had been made by reconnaissance flights and submarine scouting, but some longitudes were still wrong. Indeed, Morison recounts that "near the end of the approach, when the navigating officer of a transport was asked by the captain for his ship's position, he replied, 'About three miles inland, sir!'" Morison further recounts the scene of the landing in the following passage: From the difficult landings at Guadalcanal and the New Georgias, Admiral Wilkinson had learned a significant lesson about the necessity of rapid unloading and getting his slow, vulnerable transports away from the landing area. To this end, he only loaded his transports half full and his cargo ships one-quarter full, and made sure that 30% of the troops on the beach assisted in unloading. The Japanese, having been taken by surprise, were unable to mount an air assault on the invasion fleet. Admiral Wilkinson, grateful that his transports were able to land almost the entire troop contingent and a large amount of materiel unmolested by air attack, ordered them out of the area around sundown. Japanese response Japanese forces around the landing area were limited to no more than platoon strength, as they had not expected a landing in the area and their logistics system was unable to support greater numbers. When word of the landings reached Rabaul, Vice Admiral Tomoshige Samejima, Commander of the Japanese Eighth Fleet, immediately embarked a thousand troops from the II Battalion, 54th Infantry Regiment onto five destroyer-transports at Rabaul and sent them to Cape Torokina to effect a counterlanding. Escorting the transports was a force of two heavy cruisers, two light cruisers and six destroyers led by Vice Admiral Sentaro Omori. During the night voyage to Torokina, the Japanese ships were spotted by an American submarine and possibly by a search plane.