First, we must address a question that has been in everyone’s mind since we entered Kula Gulf that night—Japanese submarines. This is one area where we have good, reliable, detailed records. We know with considerable precision where the Japanese submarines were directed to operate and what they were assigned to do. In brief, we can be fairly well assured that there were no Japanese submarines of any type anywhere near Kula Gulf on the night of 4–5 July.
Second, you also can put to rest any speculation that we might have hit one of the mines that we laid on the night of 14–15 May off Kolombangara. The Japanese swept those mines the next day, and they had used that route regularly since then. We were nowhere near this old minefield location when we were torpedoed.
Finally, we saw the wake of the torpedo and hear the torpedo on the sound gear.
But there was a big factor, the Vila Express—(the Vila Express also made a run to Kula Gulf on the night of 4–5 July).
The Japanese were as uninformed about the US forces converging on the Kula Gulf area as we were about the operation of the Vila Express. The Japanese had selected the dark night of 4–5 July for reinforcement of the Kula Gulf area with the first increment of 4,000 army troops from the Shortland Islands. As many as possible of these troops were transported that night by the Vila Express made up of four destroyers.
These four Japanese destroyers were scheduled to arrive on the Kolombangara side of the entrance to Kula Gulf shortly after midnight. (Just by coincidence, this happened to be shortly after our cruiser task force arrived on the New Georgia side of the entrance. At that time, these two forces would have been at least 10 or 12 miles apart.
In addition to the regular crew, each of the Japanese destroyers was crammed with as many Japanese army troops as possible. The commanding officers must have been carefully briefed that it was vital to the Japanese strength in the area for these troops to be delivered as planned. Furthermore, it must have been stressed that the ships could not afford to risk a naval action with such a large number of troops on board.
As expected, the night was dark and overcast (a new moon had already set). There were occasional rain showers throughout the area. The Japanese had no radar. The Vila Express appears to have been unaware that the cruiser task force had entered Kula Gulf ahead of them. (The landing group was not yet in Kula Gulf. It would not pass Point Visu, the northern tip of New Georgia, until 0030.) Remember the seaplane mentioned earlier that had departed Rekata Bay for a rather obvious rendezvous north of Kolombangara? Could this rendezvous have been with the Vila Express so the seaplane could help serve as the “eyes” of the Japanese landing operation? It seems that the timing and location would have been about right.
It appears that at some point the Vila Express broke up into two groups. One group of destroyers proceeded across the Gulf—possibly headed for Rice Anchorage or Bairoko Harbor to disembark the troops. The second group of two destroyers continued down the coast of Kolombangara to disembark its troops somewhere in the Vila-Stanmore area.
At some point, all four ships received warning that unidentified ships were in the Gulf. This seems to have occurred even before bombardment commenced, but, in any event, it certainly occurred at 0026 when the cruisers opened fire. At that time, we can assume that the identity of our task force was pretty clear.
The two Japanese destroyers that were proceeding toward Rice Anchorage must have realized that they were located along the exit track of the cruisers and promptly took up course and speed to exit the Gulf. Their subsequent action may also have been influenced by the approach of the US landing forces. At 0031, one minute after passing Point Visu, Ralph Talbot picked up these two destroyers on the radar screen at 5 miles bearing 290 degrees and proceeding northwest at 25 knots. (Japanese destroyers were the only ships that could have been making 25 knots in that location at that time.)
(We need to pause to point out that Morison’s book states that these two destroyers possibly fired the torpedo that sank Strong. This seems to be in error for three reasons. First, he said that Ralph Talbot was near Boli Point when it picked up two “blips” on the radar screen, The war diary and action report of the Ralph Talbot state clearly that Ralph Talbot had passed Point Visu one minute prior to this time. That places the two Japanese destroyers about 20 miles from the place where Strong was torpedoed—nine minutes later. Furthermore, a torpedo wake from these two ships would have arrived from a direction sharp on the starboard bow of Strong at the moment of impact. The torpedo actually came from just forward of the port beam. Finally, Ralph Talbot picked up two “blips.” At 5 miles four destroyers would have produced four “blips.” Where were the other two destroyers? We can only conclude that the two Japanese destroyers tracked by Ralph Talbot did not fire the torpedo that hit Strong.)
The two Japanese destroyers proceeding along the coast of Kolombangara appear to have moved in close to the shoreline and held position. Perhaps one or both of these destroyers was attempting to follow along well behind the bombardment group and land troops after the bombardment force had departed. In any event, these were the only Japanese ships in position to have fired the torpedoes. We use the term “torpedoes” because it seems certain that a spread of torpedoes was fired.
You will note that Strong was torpedoed 17 minutes after the cruisers started the bombardment. During that time there were three course changes involved (two on the bottom leg). There was no way for the Japanese destroyer to obtain an accurate solution. The best that could have been done was to estimate future course changes and fire a spread of torpedoes on a bearing hoping to get one or more cruisers. Well, they mussed. They hit us instead.
But events didn’t turn out as the Japanese planned, and they had to be very cautious—especially with all those troops aboard. We didn’t sink immediately, and other US ships remained nearby. There was illumination in the area. There also must have been a recognition problem in operating so close to Kolombangara right after the cruiser bombardment. The Japanese land forces easily could have become “trigger happy.” We can only guess that the two destroyers would have been content to remain as close in to a sheltered cove as possible to escape detection and to minimize exposure to new groups of their own shore based guns. (Other than for the total number of Japanese troops involved, we do not know anything about the total load-out of these two destroyers, and we do not know why the second destroyer appeared never to have fired torpedoes.)
The Vila Express later reported that they had been unable to unload troops because of US interference. But here it is important to note that they took credit for some effective offensive action—they reported that they had sunk two ships.
They certainly had heard two major underwater explosions. Could both of these explosions have been associated with some action they took? The first certainly was. Strong was torpedoed. The second was the explosion of Strong as it sank. There are reliable reports that at least one torpedo wake passed under the Chevalier at the instant of the explosion of the sinking Strong. The wake of this torpedo came from the general direction of the most probable location of the two Japanese destroyers near Kolombangara. Forty minutes had elapsed since the spread of torpedoes which first hit Strong. That would be about right for the average demonstrated torpedo reload time for Japanese destroyers of that era. The torpedoes would not have been detected since the sonar on Chevalier was inoperative. It appeared that this last spread was running too deep to hit Chevalier but not too deep to hit the Strong.
It may be difficult (and unimportant) at this late date to shake the old notion that the explosion of the sinking Strong was cause by depth charges; nevertheless, there is a real possibility that the explosion was caused by a second torpedo.
On the other hand, there certainly was every opportunity for the depth charges to explode. Even though the depth charges were certified to be on “safe” before we entered Kula Gulf, no less than four separate groups later reported setting all or part of the depth charges on “safe” after the torpedo hit! At least one of these groups reported other wondrous exploits—which proved to be grossly inaccurate. Did the last group in this parade actually set the depth charges—or did they malfunction at 18 feet as rumored?
Sorry, we don’t know the answer. You’ll have to take your choice between a second spread of torpedoes, the depth charges or both.
We can only tell you that the Vila Express never did get to offload the army troops that night.