SEPTEMBER 2009 — It was the second-largest disaster at Pearl Harbor during World War II, but unlike its predecessor, this one didn’t make the papers. That changed this spring, when the U.S. Navy held a ceremony to commemorate the 65th anniversary of what is known as the “West Loch Disaster,” a huge, non-combat-related explosion that killed more than 160 men and wounded almost 400.

It was on a quiet Sunday afternoon, May 21, 1944, that death and destruction descended once again on the naval base. A collection of 29 large landing ships were nestled together in a section of the harbor known as West Loch, which served as the staging area for the Pacific invasion fleets. Army troops were loading mortar shells aboard LSTs brimming with fuel and ammunition for the landings on Saipan when an explosion suddenly rocked one of the ships.

As the fireball grew, red-hot fragments showered down onto the closely clustered vessels, igniting gasoline drums and munitions lined up on the decks. One by one, explosions began ripping the fleet apart, and started fires that burned for 24 hours.

Investigators were never able to confirm what caused the spark, though some suspected a mortar shell may have exploded while being loaded. Along with the death toll, 20 buildings burned, 9 ships were destroyed, and dozens more were damaged. Still, firefighters prevented the blaze from spreading to the entire invasion force, and the Saipan operation was never delayed.

The stoic response to the disaster wasn’t the accident’s only legacy. Although the incident remained secret for years, a few months after the West Loch disaster, when an explosion at the loading docks of the Port Chicago naval base near San Francisco killed more than 300 sailors, the navy began to make drastic changes in its procedures for handling ordnance. Not only were munitions redesigned for safer handling, the navy stopped nesting ships together while live rounds were being loaded.

“The navy has learned many valuable lessons from the events of 65 years ago,” Capt. Drew Mogart, director for logistics current operations for the U.S. Pacific Fleet, said during the ceremony this spring. It may not be as infamous as the attack on Pearl Harbor, but the disaster at West Loch, too, had its silver lining.