HTMS Sattakut

On a cold day in February 1944, little would the workers of the Commercial Iron Works in Portland, Oregon, have known of the fate and unlikely resting place of the USS LCI(L) 739—now known to those who visit her as the HTMS Sattakut.

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After seeing out her years in both the U.S. and Thai navies, The HTMS Sattakut has now found her final resting place in the Gulf of Thailand just off a little island called Koh Tao.

Commissioned on February 27 as a Landing Craft Infantry Large, she was assigned to the Asiatic-Pacific Theatre to assist with the war efforts against Japan. It was in September of that year when she finally saw action in the long running battle between the two superpowers when she participated in the capture and occupation of southern Palau islands between September and October of 1944.

With American military leaders predicting the invasion would last just a matter of days, it was soon clear that the Japanese had learned from previous mistakes and had themselves dug well into the hills behind the beach.

Their strategic position led to one of the largest losses of life for U.S. forces in the Pacific, with their landing craft and troops reaching the beach amid heavy fire from machine guns and artillery. The slow but steady advance of American Marines did, however, eventually lead to the surrender of the Japanese army on the island, with both sides incurring heavy losses.

With the Palau islands secure, U.S. forces moved on, securing other key islands and airfields in an attempt to cripple the Japanese and halt their advance across the Pacific. One such island would become part of one of the most controversial decisions made during the war, the invasion and occupation of Iwo Jima.

The 739 was reclassified to the USS LCI Gunboat 739, with the addition of larger guns, providing her with the much-needed firepower to deal with the heavily defended Japanese.

The naval fleet bombarded the island with shelling and mortar fire for three days running up to the landings, with little impact to the Japanese in their dugouts. Even with the piece of land being deemed useless to both the U.S. Navy and Air Forces, what followed was a gruesome and bloody five-week battle that saw more American troops killed or wounded than Japanese forces for the first time in the war.

Although American success was almost guaranteed, the Japanese showed impressive military tactics in their defence of the island. With nowhere to retreat to, U.S. forces finally overcame the resilient Japanese, leading to one of the most iconic photographs of the war, Raising the Flag on Iwo Jima, by Joe Rosenthal.

The USS LCI 739’s next action came later that month during the invasion of Okinawa, the largest amphibious assault of the Pacific war. Landing craft such as the 739 played a huge role in the invasion and were used for a variety of roles throughout this campaign.

As well as transporting troops for beach landings, they carried out vital roles including protecting underwater demolition divers, and creating smoke screens to hide the advancing fleet from enemy aircraft and artillery. For this, the 739 was armed with even more firepower, and was reclassified to a Landing Craft Infantry Mortar, with the addition of large heavy mortar cannons.

Between March and June of 1945, both sides suffered large loss of life throughout the long and gruelling invasion. However, the eventual capture of the island played a major role in the American advance. Situated just a short distance from mainland Japan, it gave the Americans the perfect base for their final assault on the Japanese.

The atomic bombings of Nagasaki and Hiroshima, which came just a few months later, finally bought an end to the war in the Pacific, and after 1946, most Landing Craft Infantry were retired from duty and were either sold, scrapped or transferred to other nations. The 739 was one such vessel, and after receiving three battle stars for her services during the war, she was transferred to the Royal Thai Navy and reclassified as the LCI 742 or HTMS Sattakut, where she would see out her years helping to transport Thai troops for training and duties.

The sinking

As part of an artificial reef project in Thailand, the HTMS Sattakut as well as many other vessels were donated by the Thai Navy to a number of locations around the country. It was chosen that the HTMS Sattakut would be sunk off the coast of Koh Tao, a small island in the Gulf of Thailand, and a mecca for recreational divers.

The vessel spent some time being stripped clean by the Department of Marine and Coastal Resources, readying for its final goodbye, leaving an empty shell with both the bow and stern cannons still attached. All electronics, contaminants and engine parts were removed before she was deemed fit to sink.

On 18 June 2011, accompanied by a large flotilla from the Thai Navy, plus dozens of local dive boats keen to watch the vessel go down, the ship was towed into her intended position. In typical fashion, not everything went exactly to plan, with Mother Nature doing her best to intervene. Large waves, strong wind and a wall of sideways rain rolled in causing many of the onlookers to head back to the harbour leaving just the Thai Navy and a few dedicated spectators to watch her final act.

The rough weather caused the ship to drift out of position and roll over as she went down. She landed on her side on the sea floor slightly off from the intended area. A small amount of damage was done to the wreck as she hit the sea floor in a great cloud of silt, but this did not deter the hoard of local divers keen to get the first glimpse of Koh Tao’s latest wreck. After a few days to let the silt and the wreck settle, the Thai Navy declared the wreck safe to dive and the divers rushed out and began diving her straight away.

After around a month of successful diving, the decision was made to raise the wreck, placing her upright and in her intended position, away from the busy shipping lane. Diving was halted while a team of salvage experts was assembled, and with the help of a large crane and platform, the ship was moved to the position she can be found in today. Laying in around 30m of water just a minute swim from the large granite pinnacles of the neighbouring dive site, Hin Pee Wee, she sits in the ideal position to be accessed year round by divers of various levels of experience.

The wreck

The wreck of the HTMS Sattakut has quickly become one of the most popular dive sites to visit on the island. Everyday, avid divers and students completing their Advanced Open Water, deep or wreck courses visit to marvel over the 48m-long ship.

Over the three years she has been down, the wreck has become home to a huge abundance of marine life from tiny flatworms and nudibranches to large schools of snapper and trevally. Even a few of the famous yet illusive Koh Tao whale sharks have been spotted passing by the wreck in the clear blue water.

Inside the wreck, schools of tiny glassfish and juvenile barracuda can sometimes be found hiding in the safety of the large empty hull.

Descending down the buoy line, the first thing to appear is the large front mounted cannon on the bow of the ship, an exciting sight for the newly certified students and experienced divers alike. The bow of the ship soon looms over you as you descend down towards the sea floor.

Exploring the sides of the wreck you can peer in through the many portholes, allowing a peek into the inner compartments of the ship. Swimming the length of the vessel you soon find yourself at the wreck's deepest point, at its stern where the rear mounted cannon aims out off the back and into the blue. This is often the murkiest part of the dive with occasional thick thermoclines lying between 25 and 30 meters.

Heading back along the main deck and up a set of stairs, the old lookout and wheelhouse appear in front of you, towering over the rest of the wreck where you can take in the same view of the wreck once shared by the ships commander and officers.

All over the wreck there are various entry and exit points for trained wreck and technical divers, as well as students learning wreck diving techniques in relatively safe and relaxed surroundings. Due to the ship being cleaned and emptied, the inside of the wreck is home to large open chambers and unobstructed passageways to explore the inner sections of the vessel. Some of the deeper areas have been welded shut, minimizing risk to the overly curious diver. However, over time, some of these have rusted away or been removed to allow further exploration.

The wreck has certainly become the largest and most popular artificial reef in the waters surrounding the island. With the huge boost in tourism, local dive centres have benefited greatly by the addition of the wreck, as well as giving Open Water students a great excuse to stay on for a few more days once their course has finished!

It is a far cry from the cold iron works in Oregon 70 years ago, but the HTMS Sattakut now joins the thousands of other wrecks around the world in the oceans depths, showing that something with such destructive power can also form the basis of new life, and promote the creation of coral reefs, providing a habitat for fish and other marine life in which to thrive. ■


Nick Shallcross is a British underwater photographer based in the Gulf of Thailand. More of his work can be seen at