Saipan International Airport - History - World War II

World War II

SPN was a sugarcane field before the Imperial Japanese Navy Air Service (IJNAS) constructed a temporary landing field on the site in 1933. The landing field was used for training purposes and had two runways configured in an "L" pattern. In 1937, the Navy began upgrading the airfield for full military use, despite an international law ban on constructing military facilities within the South Pacific Mandate. Following the commencement of hostilities against the United States in 1941, the field was named Aslito Field (アスリート飛行場).

The IJNAS assigned two squadrons of Mitsubishi A6MT Zeros to the airfield in mid-June 1944. These squadrons took part in their defense of the Mariana Islands during the Battle of the Philippine Sea later that month, being almost wiped out by the American forces during the battle.

The airfield was seized by the United States Army 27th Infantry Division on June 18, 1944 during the Battle of Saipan. During the battle, a Zero from Guam actually landed at Aslito Airfield, the pilot being unaware that the field had fallen to the Americans. As it landed it was fired upon and it crashed at the end of the runway. The pilot survived and the plane was captured. The field was renamed Isely Field after United States Navy Commander Robert H. Isely who was killed on June 13, 1944, while strafing the base.

Once in American hands, Isely Field was expanded considerably to support Twentieth Air Force B-29 Superfortress operations. The XXI Bomber Command had been assigned the overall responsibility of the B-29 operations out of the Marianas bases, and Isely Field was to be used by the 73rd Bombardment Wing (which consisted of the 497th, 498th, 499th, and 500th Bombardment Groups).

The first B-29 arrived on Saipan on October 12, 1944, and by November 22, over 100 B-29s were at Isley. The XXI Bomber Command was assigned the task of destroying the aircraft industry of Japan in a series of high-altitude, daylight precision attacks.

After several months of disappointing high level bombing attacks from Isely (and the other Twentieth Air Force airfields on Guam and Tinian), General Curtiss LeMay, Commander of Twentieth Air Force issued a new directive that the high-altitude, daylight attacks be phased out and replaced by low-altitude, high-intensity incendiary raids at nighttime, being followed up with high explosive bombs once the targets were set ablaze. These nighttime attacks on Japan proved devastatingly effective, and the Superfortress missions from Isely Field led to massive destruction of industrial targets in Japan, with large industrial areas of Tokyo, Nagoya, and Osaka being repeatedly attacked by waves of American bombers flying from the Marianas until the war's end. In response to these attacks, most of the Japanese air attacks on the Mariana Islands between November 1944 and January 1945 targeted Isely Field.