Capsizing of the USS Oklahoma
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Relative to my theory, the evidence that Tom and I gathered suggested that after the first 3 or 4 torpedo hits, Oklahoma was taking on water that immediately filled her blister and internal spaces opened by the explosion. This loss of buoyancy caused an immediate list to port. The water soon found its way deeper into the ship, causing the ship to settle. The list actually paused for a moment as the inrushing water had more effect on the ship's waterline than its inclination. Oklahoma was nevertheless at a critical point on her stability curve, when she could either right herself as she sank or continue rolling to port. At that moment, a submarine-launched torpedo with an 800+ pound warhead hit, dislodging a number of hull and armour belt plates that allowed a sudden and greater influx of water into the hull. The resulting sudden loss of buoyancy pushed the ship's metacentre below the centre of gravity, creating a capsizing moment. In other words, a torpedo launched from a midget sub, hitting at just the right moment, meant the difference between the ship settling upright to the bottom or rapidly turning over.

When we found the wreck of the I-16tou, our analysis determined that the sub had fired both torpedoes inside the harbour and that the sub's commander claimed that he was successful in his mission. We looked as thoroughly as possible to find where those torpedoes had gone. After eliminating one possibility after another, we found that the USS Oklahoma was the only stricken vessel that had damage consistent with an 800+ lb. torpedo. Subsequent analysis of the evidence – written, photographic and oral – indicated that a submarine torpedo cannot be excluded from consideration. I would still like to conduct an analysis using both a flooding and finite element analysis model of the USS Oklahoma in order to test my theory that the ship might have settled upright had it not been for a larger-than-the-norm explosive warhead. Until that time, it is our contention that the first of Yokoyama's torpedoes hit Oklahoma at a critical point in her struggle to stay upright and delivered the fatal blow that caused the ship to roll irrevocably onto her side.

The moment we speculate Yokoyama's torpedo hit.