I 169 Submarine Chuuk Lagoon, Micronesia.

The story of the I 169 submarine is one of great tragedy and sadness. When US attack planes hit Truk on April 2, 1944, the submarine was loading at the wharf. As is the custom, submarines would dive to the sea floor and wait out the bombardment. When she dived, one of the ventilation ports was not fully closed. Water entered the sub and filled the ballast tanks. There were five compartments in the sub. The submariners sealed off the conning tower section where it had leaked and where the control room was and were temporarily safe in the other four compartments. This is important because the controls for operating the ballast tanks were inside the control room. The ballast air pumps were not able to be activated. I have read the accounts of the sub carefully.

Some of the men were in the bow sections and some were in the stern of the sub. After the bombing raid ceased, divers went down to assess the situation. They heard loud tapping from inside four compartments of the hull. The next day, a thirty tonne crane was sent to try to lift the sub. The sub weighed over two thousand four hundred tonnes. However, when the ballast tanks were filled with air, it became a lot less negatively buoyant. There was hope that the crane may have been enough to lift it. The crane cables did snap. The next plan was to send divers down to drill holes in the skin of the submarine and then to pump air in. This was done and took most of day two. The divers could hear tapping from inside the submarine but from only one hold. The other three holds were silent. At least some of the submariners were still alive. There must have been no visible communication with the submariners inside. The divers wanted to tell the submariners that if they opened the hatches inside the sub, fresh air was available from the ballast tanks. There was no way that they could communicate this message. The next day, there was no more tapping coming from the sub. All of the men had died.

The US bombers were conducting night time bombing raids. They had RADAR. The Japanese could not understand how the US planes could hit targets in the dark. Over the next six weeks thirty two bodies were recovered by divers. As it became more apparent that the war was going to be lost, the Japanese decided to destroy the submarine with depth charges. Almost thirty years later, a salvage operation was conducted and sixty nine complete and incomplete skulls were brought to the surface. The relatives of the submariners held a Shinto ceremnony for the dead. I calculate that there must have been either one hundred or one hundred and one men died in this terrible accident of war.






sub sub

The I169 submarine was modelled closely from British Submarine designs. It was built in 1935. She was powered by the latest diesel engines and she had significant structural improvement to the hull. Her claim to fame is that she was part of the blockade at Oahu, Hawaii during the attack on Pearl Harbour in Dec 1941. She was nearly destroyed by mines and only survived by a miracle.

The hatches of the submarine are open. Divers who have entered the sub have died from silt out in the confined spaces. You can see massive damage to the submarine caused by the Japanese depth charges when they decided to destroy the wreck in case it was raised by the US. later on.
funnel sponge


The funnel on the wreck of the Unkai Maru has collapsed on its side. You can enter the six foot round funnnell and photograph the stern pasts.



The stern rail on the Unkai Maru has this heart shapes sponge growing on it.