Submarine in the West Loch
Submarine activity inside the harbour
While scratching our heads over this conundrum, we were at the same time continuing with other aspects of the project. When Tom and I first started out with our research – well before we knew of Terry Kerby's find of the 3-section wreck – we tried to deduce where the midget sub might have gone down. Central to this query was the late-night radio signal from the sub...in order to safely make that transmission, Yokoyama would have to surface, raise his radio antenna, and transmit. Knowing that the harbour was alive throughout the night with destroyers chasing and depth-bombing shadows, alert defenders seeing periscopes everywhere (reports from the USS Maryland and Hurlbert being just two examples) and trigger-happy gunners shooting at anything that moved (including friendly aircraft), I tried looking for some out-of-the-way place where Yokoyama could stay on the surface undetected for more than just an instant. Actually, it was more than just the time needed to send the radio code letters...Yokoyama would have had to replenish the oxygen and discharge the CO2 in the sub's interior at some point or the crew would not have survived to send the radio signal at 2241. Looking at a chart of Pearl Harbor, I was struck by what might appear to a submarine commander the relative safety of the East Loch, north of destroyer moorings. I was actually prepared to recommend a search of the East Loch when we learned of HURL's discovery of the 3-section wreck.
The revelation of the 3-section wreck outside the harbour caused us to abandon our speculation about the East Loch. We could not understand how the sub would sink in the East Loch in 1941 and then be discovered today, disassembled, in the NDSA. There was an even more compelling reason to abandon our East Loch speculation...Tom and I were starting to see a pattern of observations that pointed to another backwater, the West Loch.
In particular, Tom and I were finding indications in after-action reports of submarine activity in the main channel during the 0830-0900 timeframe. At first thought to be observations of Iwasa's boat heading north toward his fateful rendezvous with the USS Curtiss and Monaghan, the reports assumed under closer examination to be movement heading down the channel, toward the entrance. The 0900 entry in the USS Bobolink's after-action report, in particular, described a possible submarine on the bank of Waipio Point, right by the entrance to the West Loch. The commanding officer of Bobolink reported a possible outbound sub at a time when the anti-torpedo gate was closed and watched. Essentially, any midget sub north of the gate at the time of the Bobolink's report would effectively be bottled up inside the harbour. What would have been that sub commander's options at that point? Did the shells fired by Bobolink at the alleged submarine force Yokoyama into the West Loch?
I had not previously considered the West Loch. With the evidence pointing us in that direction, though, its choice as a possible sanctuary for a midget sub began to make more sense. A chart recovered from one of the midget submarines detailed the military facilities in the Loch, which at that time were few. As important, the chart showed the shoreline on the Waipio side of the Loch to be completely uninhabited, with Walker Bay as a particularly attractive area for privacy.
But could a submarine have been salvaged from the West Loch without attracting attention? The West Loch disaster of 21 May 1944 immediately came to mind...in the aftermath of the accident, a major salvage effort was conducted under a strictly-enforced security blanket. Could evidence be found that would tie our submarine to that event?