“No one knows the fallacy of chasing Japanese torpedo boats with cruisers better than I.”
— RAdm. Walden Lee “Pug” Ainsworth
During the week of 6 July, the U.S. had landed troops on New Georgia to attack Munda and had recently placed Marines on New Georgia’s northern shore to seize Bairoko.
RADM Walden Lee Ainsworth received orders to protect the north shore beachhead from attack by the “Tokyo Express” and attempt to prevent Japanese reinforcements from landing on Munda.
The American campaign to take Vila was not going as expected. Naval historian Samuel Eliot Morison called it the “most unintelligently waged land campaign of the Pacific war.” Japanese reinforcements could make a difference. A “Tokyo Express” was scheduled to sail for Vila on the night of July 12/13, 1943.
The “Tokyo Express” attempting to land re-enforcements was commanded by Rear Admiral Shunji Izaki. Assigned to Izaki was a support group of one light cruiser and five destroyers: light cruiser Jintsu (flagship for Izaki), destroyers Mikazuki, Yukikaze, Hamakaze, Kiyonami and Yugure. Also assigned was a transport group of four destroyers: Satsuki, Minazuki, Yunagi, and Matsukaze. The Japanese would attempt to land approximately 1500 troops at Vila.
Assigned to Ainsworth was the light cruisers USS Honolulu (flagship for Ainsworth), HMNZS Leander, and USS St. Louis; Destroyer Squadron 21 with Nicholas, O’Bannon, Taylor, Jenkins, and Radford; and Destroyer Squadron 12 with Ralph Talbot, Buchanan, Maury, Woodworth and Gwin. Destroyer Squadron 12 had been added to Ainsworth’s force, along with the Leander, to offset the losses his force had suffered in its frequent trips through “The Slot.”
Destroyer Squadron 12 and Leander had never operated with Ainsworth before. The Americans were learning a hard lesson that a smaller, well trained group was far more effective than a larger, thrown together at a moments notice, force.
On the night of July 13th, a PBY aircraft spotted the Japanese at 0036, 25 miles away. The Allies established radar contact at 0100 and visual contact several minutes later. Ainsworth had deployed his task force in a single column with five destroyers in the front followed by the cruisers and five destroyers in the rear. The Allied force was heading west about twenty miles east of the northern tip of Kolombangara.
The Japanese Support Group, also in a single column, was proceeding southeast about 12 miles off Kolombangara. Ainsworth assumed he had complete surprise. In fact, Admiral Izaki had known of the Allied force for almost two hours.
The Japanese had invented a useful device that detected a radar’s electric pulse at a greater range than the radar itself. Izaki was able to use this device in its first operational test to accurately plot the approach of the Allied task force.
At 0106 Ainsworth turned the cruisers to starboard to bring the main guns to bare while ordering the lead destroyers to increase speed. The lead destroyers began launching torpedoes at 0110 at a range of 10,000 yards. The Japanese beat the American destroyers by two minutes, launching Long Lance Torpedoes at 0108. Izaki then turned his column north. Jintsu turned on her searchlight as the torpedoes were being released and opened fire. Honolulu closed to 10,000 yards and the Allied cruisers followed at 0112.
All allied fire was concentrated on the largest ship. In eighteen minutes between 0112 and 0130 Jintsu was the target of over two thousand shells being fired by the allies. She lost use of her engines at 0117 when she was hit by an American torpedo. Japanese Rear Admiral Izaki was killed in action during this attack.
At 0117 Ainsworth ordered his force to turn south. Leander turned and was hit by a Long Lance torpedo at 0122. Suffering severe damage, Leander retired from the battle and was escorted away by destroyers Radford and Jenkins.
Mikazuki stayed with Jintsu to assist her while the other four destroyers sped north to reload torpedos. At 0136 the destroyers turned back to the southeast to engage the Allies. At 0131 Ainsworth dispatched Nicholas, O’Bannon and Taylor to chase the Japanese destroyers. Not long after starting the chase they encountered the disabled Jintsu, launching more torpedoes into her, sinking her.
Ainsworth had to make a decision. He believed he had sunk up to six of the Japanese ships and crippled the rest. Rather than return to home base as the victor in this perceived action, he turned northwest to finish off the Japanese ships he believed to have severely damaged.
At 0156 Honolulu’s radar picked up a group of ships at a range of 23,000 yards. Unfortunately, Ainsworth was having trouble fixing the location of the three destroyers he dispatched to chase the Japanese destroyers. At 0205 he had the radar contacts illuminated with star shells and observed they were turning away as if they had just fired torpedoes. They had indeed fired torpedos after detecting the Americans radar with their new radar detection device at 0157.
Ainsworth ordered a sharp turn to port to bring all guns to bare, however, at 0208 before this order could be carried out, St. Louis was struck by a torpedo and received severe damage to her bow. Honolulu dodged a few torpedos, but one torpedo took a portion of her bow off. A torpedo dud also struck her stern. At 0214, Gwin took one torpedo amidships causing an explosion. The Japanese began retreating from the battle. Ralph Talbot fired a spread of torpedos at the fleeing Japanese, but the battle was now over.