West Loch disaster

LSTs 39 and 480 still ablaze on 22 May 1944

The West Loch Disaster was a previously secret American World War II maritime accident which led to the deaths of 163 men at the US naval base of Pearl Harbor in Hawaii on 21 May 1944. The incident is not as well known as the original Pearl Harbor disaster, the Japanese Attack on Pearl Harbor of December 1941, in part because the event was classified Top Secret until 1960.

The disaster occurred in the West Loch part of the harbor, at the time being used as a staging area for a fleet of Landing Ship, Tanks (LSTs) and other amphibious assault ships being prepared for the upcoming Operation Forager, an invasion of the Japanese-held Mariana Islands. At 1500 hrs. on a Sunday afternoon, an initial explosion occurred on board LST-353, and subsequently spread fire among the tightly packed ships loaded with fuel and munitions. The resulting fires lasted 24 hours, and led to the eventual sinking of six LSTs.

The exact cause of the disaster was never determined, but it is believed that a mortar round exploded during an unloading operation, setting off the chain reaction. The round exploded either because it was dropped during handling or ignited by a gasoline explosion. The incident, together with the Port Chicago disaster two months later, led to changes in Navy ordnance-handling practices.

The wreckage was quickly cleared in a salvage operation and dumped at sea three miles south of Hawaii, leaving only the rusted hull of the partially beached wreck of LST-480 in the loch as present-day evidence of the disaster. The remains of a Japanese midget submarine later found in the salvage is believed to be the fifth and final unaccounted-for Japanese midget submarine used in the 1941 attack.

Background

Pearl Harbor naval base

In May 1944, the West Loch area of Pearl Harbor was unusually crowded with various vessels as it was being used as a staging area for the upcoming Operation Forager. Twenty-nine Landing Ship, Tanks (LSTs) were tied up, beam to beam, at six Tare piers. Many of the LSTs, in addition to carrying their own munitions and fuel, were already fully loaded with cargo - all the munitions, fuel, vehicles, equipment, and other general stores required by the Marines for the invasion, due to begin in mid-June. This included high-octane gasoline stored on deck, ready for quick deployment ashore after landing.

In the weeks leading up to the incident, the vessels and crews had been training for the upcoming invasion. The LSTs were each crewed by around 120 Navy sailors or Coast Guardsmen, and manned by around 200 Marine loaders, drivers and mechanics. As a result of the rapid expansion of the fleet, many of the sailors and Marines were inexperienced. Following a week of training, on the day of the incident, a Sunday, many were on shore leave; consequently, many of the LSTs had only half their crew aboard.

Explosion

The disaster began on Sunday 21 May 1944. At 1508 hrs. an explosion emanated from LST-353 moored at Tare 8, sending a large fireball into the sky. The explosion was heard miles away at Pearl Harbor HQ, followed immediately by more explosions of increasing intensity, sparking fears of a Japanese attack or an earthquake. A chain reaction of explosions was initiated as fire and debris rained down on the fuel and munitions stored on the decks of other LSTs. In minutes, 200 men had been blown from the decks into the water. Eleven wooden buildings on the shore were destroyed, and vehicles blown on their side. In all, 20 buildings were damaged.

Initial fire-fighting efforts by crews were impeded by the heat, although some crews further away managed to muster damage control parties. Many of the LSTs tied together at Tare 8 began to sink. Fires also spread to Tares 7 and 9. Within the hour, Admiral Richmond K. Turner was directing fire-fighting efforts from a launch.

Various LSTs, some under their own power, some assisted by tugs, managed to move to safety, while others drifted, abandoned, spreading the fires and sinking in the channel. Leaking oil ignited on the water also spread fire to other Tares otherwise untouched by the chain reaction.

Tugs and foam-carrying salvage ships from Pearl Harbor eventually arrived to fight the spreading fires. Explosions and fires continued into the night, with the last explosion occurring at 2230 hrs. Fires continued for 24 hours. Another vessel steered a drifting LST away from a collision course with an ammunition ship docked across the loch at the ammunition depot.

Harbor tugs USS Osceola (YTB-129), USS Hoga (YTB-146), USS Geronimo (YTM-119), net tender USS Tamaha (YNT-12), chartered tug Mikioi, and smaller tugs YTL-233, 306, 307, 308, 309, and 339 were damaged while engaged in fire control efforts.

Casualties

The initial official account listed 27 dead and 100 missing. The majority of sources state the final death toll as 163 men, with a further 396 wounded. In an account published in Sea Classics magazine in 2005 however, the total dead is put at 392, of which 163 were sailors, the remainder being Marines (part of the Department of the Navy) from the newly formed 2nd and 4th Marine Divisions, with records of Army dead having not been recorded in the confusion. Pearl Harbor attack survivor and historical researcher Ray Emory also disputes the death toll, stating that 132 men died at West Loch.

Investigation

LST-480 burns again on 23 May 1944. The sunken LST-353 where the disaster originated lies off her starboard bow

A Naval Board of Inquiry was opened in Pearl Harbor the following day, under Rear Admiral John F. Safroth. Early thoughts that the incident was the result of a Japanese submarine attack were dismissed as impractical, because of the depth of the loch and the presence of anti-submarine nets.

The executive officer of LST-353 stated that immediately prior to the explosion, Army stevedores were unloading mortar ammunition from a Landing craft tank (LCT), itself a small vessel, lashed to the deck of the LST. The 4.2 inches (11 cm) mortar rounds had been mistakenly loaded onto the wrong vessel. According to one source, it had been realized during training that mortars could not be accurately fired from LCTs, and this was the reason for the unloading taking place. Eighty drums of fuel were present 15 feet (4.6 m) from the LST's elevator being used in the unloading process. The unit tasked with unloading the mortars had received no training for the task.

Neither the initial investigation, nor subsequent reviews, found a conclusive cause for the disaster. The two most likely causes were considered to be the accidental dropping of a mortar round being unloaded on LST-353, or the ignition of gasoline vapors from drums stored on the deck of LST-353. The Navy determined that a mortar round did explode on LST-353, sparking a chain reaction, but could not determine why, as all those nearest the explosion were killed. It noted that in addition to a handling error, fuel vapors could have been ignited by careless smoking (although banned), and that welding had also been occurring that day.

No courts martial or letters of reprimand were issued to anyone involved, and the dangerous practices of closely loading fuel and munitions aboard closely nested vessels were all described as necessary under the conditions of war, and the layout of Pearl Harbor. A recommendation to avoid nesting in future was criticized by Admiral Nimitz as impractical.

In his eye-witness testimony, Lt.Cmdr. Joseph B. Hoyt, USNR, Commander of LST Group 39, Flotilla 13, citing the efforts of the crew of the badly damaged but saved LST-274, criticized the crews of many of the other LSTs for abandoning their vessels too early, leaving them to sink or drift, rather than fire-fighting or attempting to beach them elsewhere. Several crews and skippers were called to account for inadequate reactions to the emergency, although the severity of the conditions were cited as mitigating factors.

Coverage

A press blackout was ordered following the incident, and the official inquiry was marked Top Secret. Survivors and eye-witnesses were not permitted to mention the incident in letters home. Four days after the incident, the authorities released a one-paragraph statement noting an explosion had caused "some loss of life, a number of injuries and resulted in the destruction of several small vessels". It was only after Operation Forager that a fuller account was released. The incident was not de-classified and made public until 1960.

As a result of the secrecy surrounding the incident, it has been asserted that the public knows little about Pearl Harbor's "second disaster". As of 1997, the only book about the incident, The West Loch Story, was privately published by William L.C. Johnson, a survivor, in which he alleged that a full account had not emerged from the Navy until 1964, and that the incident had been caused by careless smoking.

Impact on Operation Forager

Six LSTs were sunk (LST-39, LST-43, LST-69, LST-179, LST-353, and LST-480), two already carrying smaller, fully loaded Landing craft tanks (LCTs 961, 963 and 983) lashed to their decks. Several LSTs were damaged and/or ran aground. Four (including LST-205 and LST-225) could not be repaired in time for the invasion. Seventeen tracked landing vehicles (LVT) and eight 155-mm guns were destroyed. Other sources place the total number of destroyed LSTs at nine. With reinforcement of the fleet from elsewhere, and through quick repair efforts, Operation Forager was only delayed by one day as a result of the incident, with the operation commencing essentially as planned three weeks later.

Memorials

The rusting remains of LST-480.

In the weeks following the disaster, all wreckage was salvaged and removed, with the exception of LST-480 (sometimes reported as LST-353). Its bow can be seen at 21°21′25.91″N 157°59′49.87″W, rusting, the craft having been beached during the disaster. In April 1995 the first memorial to the disaster was unveiled: a table-sized plaque sited on the shore of the loch. At the behest of Congress, gravestones of unidentified victims in the National Memorial Cemetery of the Pacific were amended in the 2000s from recording simply "unknown", to "Unknown, West Loch Disaster, May 21, 1944". The Navy commemorated the 65th anniversary of the disaster on 21 May 2009.

Legacy

As a result of the incident, and the Port Chicago disaster two months later, the Navy drastically changed their ordnance-handling procedures, insisting on training for handlers, redesigned munitions for safer handling, and no longer nesting vessels when ammunition was being handled.

It is also possible that the salvage operation undertaken to clear the loch after the disaster inadvertently lengthened the hunt for the 'fifth midget sub' involved in the 1941 attack on Pearl Harbor. After three pieces of a midget submarine were discovered three miles south of Pearl, a working theory was developed that this was the only submarine in a group of five Japanese Ko-hyoteki class submarines involved in the attack that had not yet been accounted for. Researchers posited that it had penetrated the harbor to attack Battleship Row, before escaping into West Loch and being scuttled by the two-man crew. Lying on the bed of the loch, it was then salvaged along with the remains of the LSTs, LCTs and landing tanks, and then dumped out to sea.

See also

• List of accidents and disasters by death toll#Explosion