Losing their Hearts in San Francisco:  The San Francisco Maru of Truk Lagoon


“Come back.  Even as a shadow, even as a dream.”  ~Euripides, Greek classical tragedian playwright

Built in Japan in 1919 by the Kawasaki Dockyard, The SS (Steam Ship) San Francisco Maru was a medium-sized freighter of the time specifically designed for the Japanese Yamashista Kisen Line.   She was a 385ft, 27ft beam, 5,800+ ton passenger-cargo ship that served as part of Japan’s wider commercial fleet involved in world-wide trade.  The word “Maru,” meaning “circle” in Japanese, has been used to designate a Japanese merchant vessel since the 16th century.  Although the exact reasoning of this particular ship-naming convention is lost to time, the idea of a safe circular journey for ships and their crews is probably not far from the mark.  As to the city-name?  The Japanese at the time often named ships to reflect their primary destinations.

The San Francisco Maru

The San Francisco Maru

During World War II the Japanese were in desperate need to meet the logistical needs of their new Pacific empire, suddenly stretched far, wide, and thin.  Many commercial vessels were thus taken into service of the Emperor, a fate no different for the San Francisco.  Following her requisition by the Imperial Japanese Navy, the ship was detailed to transport military cargoes between the Japanese homeland and far-flung Pacific destinations.  Like most of the other Japanese merchants during WWII, the San Francisco was armed, in this case with a single 75mm/3” deck gun forward to both defend against surface submarine attack, and to provide an opportunity to attack and capture other unsuspecting merchants she happened to meet along the way.

Although damaged by aerial bombing in 1943 while delivering supplies in New Guinea, the San Francisco suffered her fatal blows after arriving at Truk Lagoon (current day Chuuk, part of the Federated States of Micronesia) in February 1944.  Packed with war materials, including cargo holds full of bombs, mines and torpedoes, she arrived just days before a massive American attack on this Japanese stronghold.  During Operation “Hailstone” (ラック島空襲 Torakku-tō Kūshū, lit. “the airstrike on Truk Island”) between 17-18 February 1944, waves upon waves of US Navy carrier-based planes were launched against shipping found at Truk, as well as the significant military presence Japan had built up there since the end of World War I.  After the first day’s attacks, the San Francisco was observed and reported by US forces as being on fire with smoke belching amidships.  The next day, she was reportedly hit by at least six 500-lb bombs, and was left burning furiously and sinking stern first.  At least five crew members were killed.  Operation Hailstone is often referred to as the “Japanese Pearl Harbor” due to the massive damage inflicted on the Japanese fleet.

Basic Orientation of the Wreck Today

Basic Orientation of the Wreck Today

It’s position lost to the fog of war made even more obscure by the passage of time, the wreck was “discovered” in 1969 by Cousteau (no doubt with the help of locals who all but knew her location), but was not dived again until 1973 when the ship’s bell was recovered and her identity confirmed.

Bow Gun of the San Francisco

Bow Gun of the San Francisco

The San Francisco lies very deep, and rests on an even keel with the superstructure beginning at ~140fsw, weather deck at ~165fsw, and the sea bottom around 210fsw.  Upon descent, her wreck remains invisible, and only passing about 50’fsw do her twin masts first come into view, themselves reaching up only to 105’fsw.  Heading from the forward mast to the bow, you cross over the open access to cargo hold 1 and finally reach the vessel’s most impressive and picturesque deck gun at ~150fsw.  Most deck guns of the wrecks in Truk are covered with an immense amount of growth, but due to the depths of the San Francisco, this is not that case of her wreck.

Hemispherical Mines of the Forward Cargo Hold

Hemispherical Mines of the Forward Cargo Hold

After touring the gun – a must on this shipwreck in Truk – one should immediately descend down into hold 1 forward, where you will find a cargo space packed with hemispherical landmines, at one time destined to help defend the beaches and shallow waters of Truk Lagoon against potential Allied invasion.  Watch the depth here though; the hold descends down to almost 200fsw!  Exiting up and aft out of hold , immediately proceed aft and around the forward mast to hold 2, where divers will find a plethora of scattered aerial bombs, complete with tail fins and the remains of their original wooden packing crates, along with the remains of Japanese trucks in the hold’s ‘tween decks.  Still deeper, drums of fuel can be seen.

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Perhaps the highlight of visiting the San Francisco, however, are the three iconic Japanese tanks still found resting on the ship’s main deck.  These tanks, built by Mitsubishi, are Japanese Light Type 95 HA-Go tanks covered in with ½” armor.  They appear toyishly small in appearance, but would have been manned by a crew of three and could make up to 30mph on a six-cylinder, air-cooled 120hp diesel engine.  Weighing ~7.5 tons, the tanks were armed with three weapons:  a 37mm main battery turreted gun, and two 7.7mm machine guns, one forward (non-coaxial) and one rear-facing.  The tank was only mildly effective against infantry and was never designed for armored battles, and with an extremely cramped interior, only the lightest armor, and a hand-operated turret, the tank suffered enormously in battle as more modern battlefield weapons came into play.  Two tanks are found on the starboard side of the ship, with one to port.  This is perhaps the most photogenic part of the wreck, and if your bottom time is already limited (as it is on this wreck), make sure to reserve at least a few minutes for these infamous tanks.

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From here, our planned dive run time required us to start our long ascent to the surface, where we completed our accelerated decompression profiles as we went.  It’s hard to leave the wreck, especially seeing the cratered remains of the superstructure (severely damaged from bombing), and knowing that the rear cargo holds contain a mixture of trucks, crates of ammunition, more mines, some depth charges, and scattered torpedoes….  How this wreck failed to detonate under such intense bombing is hard to imagine.  Equally as befuddling is the lack of other visible damage from the other reported bomb hits of the 2nd day’s attacks.

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But exploring the 2nd half of this ship, where those five unfortunate souls who lost their hearts in San Francisco can be remembered as a shadowy dream, will have to wait for my return to Truk Lagoon.  Until then, stayed tuned for more “Traces of War” from this year’s adventures exploring this iconic battle site.