BURMA-INDIA (Tenth Air Force): HQ 311th Fighter-Bomber Group transfers from Nawadih to Dinjan, India.
CHINA (Fourteenth Air Force): 8 B-24's bomb the town areas of Tengchung, China, and Sadon and Myitkyina, Burma. The 75th Fighter Squadron, 23d Fighter Group, transfers from Kunming to Kweilin, China with P-40's.
JAPAN: The submarine USS Wahoo is sunk in La Perouse Strait off the coast of Hokkaido with its ace skipper, Commander Dudley "Mush the Magnificent" Morton. During five patrols, Morton and Wahoo sank 19 ships. Japanese records report that, on 11 October, the date USS Wahoo is due to exit through La Perouse Strait, an antisubmarine aircraft found a surfaced submarine and attacks, dropping three depth charges sinking the sub.
Also on 11 October 1943, the commander of a Japanese shore battery overlooking Soya Strait reports sighting and firing on a surfaced submarine. A number of hits are claimed before the submarine dives and an aircraft from Ominato is sent to the spot. At 0920 hours, the plane detects an oil patch and the shadow of a conning tower and bombs are dropped on this shape. The aircraft radios for assistance and circles until other planes arrive.
A submarine is positively identified and more bombs are dropped until surface ships, including HIJMS Submarine Chasers 15 and 43 arrive. These, and other ships, drop depth charges. HIJMS Submarine Chaser 15 reports part of a ship's propeller thrown to the surface by an underwater explosion. More aircraft and HIJMS Auxiliary Minesweeper 18 arrive, but nothing more of the submarine is seen.] USS Wahoo is announced overdue on 2 December 1943 and stricken from the Navy list on 6 December 1943.
SOUTH PACIFIC THEATER OF OPERATIONS (Thirteenth Air Force) 22 B-24's join 30+ USN dive bombers in pounding Kahili Airfield and the nearby area. Hits are scored on the airstrip, fuel dumps, supply areas, gun positions, bridges between Rangu and Jakohina, barges at the mouth of the Uguima River, and several other targets. The B-24's and the USN and AAF fighters covering the attack claim 12 Japanese airplanes downed.
Japanese aircraft attack U.S. shipping off Koli Point, Guadalcanal, torpedoing two merchant freighters.
NEW GUINEA: Over Northeast New Guinea, Colonel Neal Kearby, Commanding Officer 348th Fighter Group, Fifth Air Force, shoots down six Japanese fighters, four Zeros and two "Tonys" near Wewak, Northeast New Guina. He is awarded the Medal of Honor for this action.
In Dutch New Guinea, USAAF Fifth Air Force B-24s attack Manokwari, Bira, and Fakfak and score hits on a small vessel at Fakfak.
EAST INDIES: During the night of 11/12 October, 5th AF B-25s bomb Cape Chater and Lautem Airfields on Dutch Timor Island in the Netherlands East Indies.