a fast run up the New Georgia Sound, also known as "The Slot". When Ryan's destroyers were off the north coast of Kolombangara, lookouts on watch saw a burst of anti-aircraft fire in the distance, giving away the position of the Japanese convoy. Despite a full moon, visibility was limited to due to low lying clouds and intermittent rain showers. However, at about 23:30, the Japanese convoy was attacked by eight AirSols Avenger torpedo bombers, and forced to scatter, although no ships were damaged. Two of the escorts, Isokaze and Shigure, sailing abreast, began herding the smaller craft back into formation, while Sazanami and Hamakaze continued on a northwesterly course. Ryan was advised by the Avengers the Japanese ships were still heading for Vella Lavella, although his destroyers were detected shortly afterwards by a Japanese reconnaissance aircraft, which began circling in preparation for an attack. The convoy was still reforming, when at 00:29 on 18 August, Ryan's radar detected the Japanese destroyers to the northwest, at a range of , then the Japanese barges; at 00:32, Japanese lookouts spotted the U.S. destroyers, which had closed to . The Japanese convoy was still short of its destination, and Ijuin was under orders to avoid decisive engagement. He dispatched two of his destroyers to turn to the north in an effort to lure the U.S. force away from the troop carrying vessels. To conceal his position, Ryan decided not to use his deck guns, and began maneuvering for a torpedo attack on the Japanese destroyers, rather than attacking the barges. This surprised Ijuin who had expected the opposite. Around 00:40, the Japanese aircraft dropped several flares over the U.S. ships, giving away their location, and Ryan turned back to engage the convoy to his east. Ijuin ordered his ships to begin firing torpedoes six minutes later, loosing 31 between 00:50 and 00:54 at a range of . By making a series of turns to avoid the Japanese barges, the American destroyers unintentionally avoided all 31 torpedoes, and around 00:56, the Japanese gunners opened fire. However, to avoid revealing their position, their searchlights were turned off, and no damage was inflicted on Ryan's destroyers. After a series of turns, the U.S. destroyers opened fire with radar controlled 5-inch guns at 00:58, which damaged Hamakaze, while Chevalier loosed a salvo of four torpedoes towards Shigure from a distance of . This attack was unsuccessful.