World War II Database

Contributor: C. Peter Chen

ww2dbaseCommander Moriyoshi Yamaguchi was a 20-year veteran of the Japanese Navy with 2,000 hours in the air as a pilot. During the Pacific War, he held various air commands. Between Dec 1941 and Sep 1942, he was a staff officer of the Fourth Fleet in the South Pacific. Between Oct 1942 and May 1943, he was an instructor with the Training Air Corps. Between Jun 1943 and Mar 1944, he served with the 202nd Air Corps in New Guinea. Between Aug 1944 and Jan 1945, he was with the 2nd Air Fleet in Taiwan and then Luzon, holding roles such as staff officer, operations officer, and commanding officer of the First Combined Base Air Force at Luzon. Between Feb 1945 and the end of the war, he served with the 1st Technical Arsenal. After the war, he was interrogated by Lieutenant Commander James A. Field, Jr. of the United States Naval Reserves in Tokyo on 26 Oct 1945, with the interrogation focused on Japanese air forces during the Philippines Campaign of 1944. Field commented Yamaguchi to be "entirely cooperative, sometimes it was feared to the extent of inventing answers in order to be helpful rather than confessing ignorance of the questions at issue." He further stated that "many of the statistics [Yamaguchi] offered, particularly as regards losses and replacements of aircraft, are believed to be in error and should be accepted only with considerable reservation.... [H]owever, this very inaccuracy is important evidence of the deterioration of the Japanese position and of the disorganization of Japanese forces in the Philippines." Yamaguchi believed that Philippines were lost because of the American air and naval superiority in 1944, critically threatening all Japanese shipping of men and supplies to the area. He also noted that by this time Japan began to experience shortage in fuel, which played a role in the reduced capacity of sea-going transports, also.