West Loch: The Pearl Harbor Disaster No-One Knows About


Everyone knows the story of the attack on Pearl Harbor, but few people are aware there was a deadly event there in addition to the Japanese attack. Known as the West Loch Disaster, the incident occurred in May 1944, resulting in 163 deaths and almost 400 injuries, as well as the sinking of six ships.


It happened as the US Navy was gearing up for Operation Forager; the invasion of the Mariana Islands held by the Japanese. The incident was the result of inadequate training and bad management, and resulted in new naval procedures, to prevent another such occurrence.

So What Happened?

At the time, Pearl Harbor was a staging area for the Mariana invasion. As such, there were nearly 30 ships, all tied together and loaded with different types of ammunition and fuel, to provide support for the offensive. Many were landing vessels, each crewed by service personnel who were undergoing training in US Navy protocol. They were inexperienced sailors or marines who had joined the war effort. As such, many were not aware of proper safety standards, endangering themselves and many others in the process.

One of the ships appeared to spontaneously explode, sending everyone into a panic, as they feared a Japanese attack or even an earthquake. With the loaded vessels all tied together, a chain reaction occurred spreading fire and shrapnel everywhere. Hundreds of men were immediately thrown into the water by the force of the explosions, and buildings on the shore were destroyed or damaged.

Ships burnt and sank at a rapid pace, despite efforts by their crews to fight the fires – although some men were accused of not doing quite enough to fight the flames. Ships nearby were moved using tugboats, and some were towed away from critical areas, but some that were on fire were abandoned and left to float until they sank. The ships continued to burn for more than 24 hours.

A NASA image of Pearl Harbor. The disaster occurred in West Loch which is to the left side of the photo, where the water is slightly green.


The official count put the death toll at 163, with 396 wounded. A more recent publication claims that nearly 400 people died, and the initial number had not counted those in the Marines and Army, only sailors.

But why did it happen at all? As the investigation began, it was quickly determined that the West Loch incident was not a Japanese submarine attack. The water was not deep enough, and there were anti-submarine nets in the area.

The wreckage of the LST 480 following the West Loch Disaster.

The inquiry discovered that before the explosion, men were unloading mortar ammunition from the deck of one of the ships. The men doing the unloading had received little training. It was possible a mortar round exploded during the operation and caused a chain reaction. However, it is difficult to surmise just what happened, as everyone at the site of the first explosion was killed. The only other plausible cause was that perhaps some fuel drums were ignited by a cigarette or welding.

The inquiry criticized many of the men who abandoned their ships and left them to burn and sink. However, due to their inexperience, no official reprimands were issued, but any unloading of munitions after that was very closely watched.

The Navy changed ordnance-handling procedures and ordered extensive training for anyone handling ammunition. Munitions were also redesigned to make them safer, and ships tied together was avoided if any ammunition was going to be involved.

One odd note: it is believed that the removal of all debris from the disaster may have prevented the finding of a Japanese midget submarine. Four of the five that attacked Pearl Harbor had been found. The wreckage from the remaining one may have been mixed in with that from the West Loch disaster and dumped.

This ship can still be seen, where it was left to rust in the West Loch.

Why Has No-One Heard Of It?

Well, the military required a press blackout following the event, as it was considered top secret. The survivors and eyewitnesses were forbidden to divulge any information in letters home to the mainland about anything having gone amiss. The military, after a few days, issued a small release saying there had been an explosion and a few deaths. Slightly more information was provided after the Mariana Islands invasion, but the full extent of the story was not known until 1960 when it was declassified. Since then, not much has been written or recorded about the incident.

There is a memorial to the event. One ship was left beached and rusting near the site of the disaster and is still visible. About ten years ago, the National Memorial Cemetery of the Pacific changed some of its tombstones to read, “Unknown, West Loch Disaster, May 21, 1944.”