Often dubbed the "Second Pearl Harbor," the West Loch disaster in Pearl Harbor, Hawaii, saw six large landing ships explode, burn, and sink on May 21, 1944, after their cargoes of ammunition and fuel caught fire. The LSTs were moored in a large formation of 34 ships preparing to take part in the invasion of Saipan in the Marianas Islands. LSTs were designed to deliver 10 fully combat-ready tanks onto beaches during amphibious landings and could carry hundreds of tons of supplies.
The LST-742 loads supplies in Korea in October 1950. The ship design was created in World War II to allow the ships to rapidly deploy tanks and other supplies on landing beaches. (Photo: National Archives)
At Pearl Harbor, the ships were carrying mostly fuel and ammunition, including mortar rounds from a failed test to employ LSTs and their smaller cousins, landing craft tanks, as mortar platforms to support beach assaults.
Soldiers were unloading mortar shells from LCT-963 and onto trucks on LST-353 on May 21 when a fireball suddenly erupted from LST-353.
Navy ships continue to burn on May 22, 1944, following the West Loch disaster the previous day at Pearl Harbor, Hawaii. The center plume of smoke is coming from LST-480 whose wreckage is still present at West Loch. (Photo: U.S. Army Signal Corps)
The Navy was never able to identify a definite cause, but an accident with a cigarette or a mortar round going off and igniting the gasoline fumes have been advanced as probable causes.
Regardless of how the first fire started, its progress through LST-353 was fierce, and the rising heat triggered a second, larger explosion that filled nearby ships with hot shrapnel and spread flaming debris through the docking area.
The flames consumed LST-353 and five other ships. The Army unit that was removing the mortar ammunition from LCT-963, the all-Black 29th Chemical Decontamination Company, lost 58 of its men. In total, 163 service members were killed and 396 wounded by the fires and explosions that raged for most of the day.
The LST-39 burns on May 21, 1944, during the West Loch disaster at Pearl Harbor, Hawaii. (Photo: U.S. Army Signal Corps)
The military also lost three LCTs, 17 tracked vehicles, and eight artillery pieces.
The Navy rallied after the incident, finding new ships and men to take over the mission. The LST fleet for the invasion of Saipan launched only one day late and made it to the Marianas quickly enough to invade on schedule on June 15, 1944.
A media blackout kept most of America from hearing about the incident until it was declassified in 1960. Even today, it remains relatively unknown.
One ship, LST-480, still rests on the beach at West Loch. The Navy and Army has worked in recent years to remember those lost and call attention to the sacrifices of those killed and wounded.