History
The San Francisco Maru was built in 1919, for Japanese world trade, and carried, among other things, coal, phosphate and bauxite but, during WWII, she also transported military cargo between Japan and the Inner South Seas.  In 1943, she was attacked and damaged by aircraft at Wewak, in New Guinea.  After repair, she arrived in Truk Lagoon on 5th February 1944, anchoring SE of Dublon Island but was left behind when her convoy departed on 12th February.  She was bombed by carrier-based aircraft from the Yorktown, Bunker Hill and Essex on 17th February, burned furiously and sank stern first, with the loss of five crew. The wreck is upright on a 64 m bottom and was identified from the ships bell in 1973.  She lies in a particularly clear part of the lagoon and is in good condition. 

Diving
Even though it's a popular dive, the Odyssey operators were anxious to assess our diving before committing to it, as it’s beyond the normal range of most deep recreational diving.  Nitrox diving the day before was kept deliberately early, shallow and short.  Tank valves were wrapped in towels and residual nitrox bled off and replaced with air. The briefing was thorough and we were accompanied this time, not just by the usual dive masters, but by the skipper himself.  I listened carefully, planning where to go, what pictures I wanted and the changes needed to the camera between pictures, as these are easily overlooked at these depths.  A spare air scuba set was placed on the ships deck, right by the up-line on the bow at 45 m, and nitrox sets were suspended at ten and five metres to cover any out-of-air situations.  Bottom time was limited to 13 minutes and this was to be a decompression dive.  It was good to see thorough preparations, as diving to these depths is not to be taken lightly, even in these ideal conditions.  We discussed dive teams.  Three of us, who had had experience at these depths, were split between three teams.  I went with Dave and Mike.

The gentle swell of the lagoon lapped Odysseys hull.  We dropped off the stern dive platform and swam slowly towards the white mooring cable that curved and slanted down into wonderfully clear, powder-blue water (28°C).  We began the descent and I checked the camera and settings.  At about 20 m, the blunt bow of a large merchant ship (117 m long) emerged from the blue haze.  At 45 m we glided over a 75 mm gun trained horizontally to port, partly obscured by sponges and soft coral, and surrounded by a circular steel framework that once supported the gun-deck.  The first tendril of nitrogen narcosis reached out gently and brushed my mind. 

The first sight of the San Francisci Maru. The framework of a circular
deck surrounds the 75 mm bow gun at 45 m, with divers for scale.

Hemispherical beach mines at 53 m are packed into the top of No 1
hold, between layers of rotting plywood.

Mines in the Hold
The foremast, aft of No 1 hold, still thrusts upward in silhouette against light filtering from the surface with its crosstrees and most of its rigging complete.  Six winches, in lines of three, lie at the base of the mast between the two forward holds.  Mines, artillery shells and cases of detonator horns were packed into the aft section of No 1 hold.  I entered the forward part of the hold between huge hatch cover beams, while resetting for close range photography.  Stacked cordite boxes formed one wall and layers of small but potent hemispherical beach mines, tightly packed between layers of rotten plywood and splashed with mauve, green and bright yellow, formed the other.  I had never been near so much high explosive before – look, photograph but don’t touch!  Torch beams probed downwards into blackness to reveal coils of cable.  Fifty three metres and my mind was sluggish – time to go back on deck to clear the head. 

A Japanese Type 95 HA-GO light tank lies skewed on the port side
with Hannes Gebauer for scale.

Tanks on Deck
Up through the blue rectangle of the hatch, checking time and air pressure.  A large grouper glided over the deck towards No 2 hold, replete with tanker and other trucks, their tanks distorted by pressure and their bodywork corroded and fragile.  Aft of No 2 hold, on the port side at 50 m, up against the framework of the bridge superstructure, lay a Japanese Type 95 HA-GO light tank, its left track mounting the port rail and its gun barrel pointing low at an unseen target off the port bow.  On the starboard side were two more light tanks, their tracks partly immersed in silt accumulated on the deck and their outlines softened by marine growth and partly screened by shoals of fusiliers.  The tanks had broken free of their restraints and crashed one into the other during the sinking, one partly mounting the other, in a deadly embrace. 

A blue-fin trevally drifts over the floor of the shattered remains
of bridge structure.

Superstructure
The open framework of the bridge section loomed beyond.  Sinking to the bridge deck, among dangling electric cables and evidence of fire and explosive damage, there were sake bottles, pots, earthenware jars, pieces of crockery, a wash basin and a magnificent squat mauve-glazed vase.  This was the domain of blue-finned trevally and batfish.  One of my buddies, probably as narced as I and over ballasted, raised a cloud of silt on the floor, obscuring visibility.  I moved upwards through the framework, some of it severely distorted by the bomb damage aft, drifted over the collapsed funnel and looked longingly at the engine room skylights in the aft superstructure, but our time was nearly up.

Luke Endacott - perhaps a tad narked

A slow ascent
Gathering the team, we rose slowly over the bridge, getting an almost map-like view, towards the foremast.  Our torches picked out brilliant orange, red and green sponges and clams beneath the crosstrees in a shaded and normally blue world.  Watching our ascent rate, we finned slowly across to the white mooring line and began the gradual ascent towards the shimmering surface; the ever-watchful crew hovered above, amidst glittering clouds of bubbles and the emergency nitrox tanks at the deco stops. 

Dragging out the decompression gave me time to ponder what I’d seen.  The concentration of munitions in that forward hold would have completely disintegrated the San Francisco Maru if she had received a direct hit there.  As with the other wrecks at Truk, I was saddened by the lives, proud ships and resources wasted by war.  However, if these munitions had been used, the loss and suffering would have been much greater.  Diving to these warm, limpid, clear depths at Truk is very different from attempting a similar dive in turbid, cold water elsewhere – perhaps deceptively easy.  This, by a small margin, was my deepest ocean dive and was truly memorable, conducted impeccably and seamlessly by the operators of Odyssey. Definitely a dive to do again!

Pictures taken with a Nikonos V on Fuji Provia 400 rated at 800 ASA
Article previously published in Dive Log Australia April 2003, No 177 pp 44-45.

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