September :
Pressure was increased on submarine operations to prevent US reinforcements from reaching Guadalcanal.
All submarines were placed under the command of Read Adm. Shigeaki Yamakazi, commander of squadron 1. However,
japanese submarine interference with the buildup on the island remained marginal.
October :
The struggle became more intense. The battleship Kongo and Haruna bombarded Henderson field at midnight on the 13th destroying some 48 of the 90 US aircraft there. The Japanese planned a total attack on the 22nd, then postponed it to the 25th. Carrier task forces from both sides clashed from the 19th till the 26th in the battle of Santa Cruz.
I-15, I-21 and I-24 sighted the US forces steaming south from Santa Cruz at a point 200 miles west of Espiritu Santo. They fired torpedoes, but no hits were scored against the fast moving targets.
The IJN fleet was larger than the american and so was its margin of victory :
Carrier Hornet sunk
Carrier Enterprise dammaged.
Carrier Shokaku and
light carrier Zuiho dammaged.
At sea the role of the submarines decame more important because of the dammage both carrier groups sustained, the boats (I15, I17, I19, I26 and I4, I5, I7, I8, I22 and I176) were to patrol around Guadalcanal.
On 20 October, during the night,
I-176 launched torpedoes and dammaged
USS Chester (CA-27).
November :
I 26
On 13 November, during the Third Battle of the Solomon Sea (American: Naval Battle of Guadalcanal), she also hit the badly-damaged cruiser
USS Juneau (CL-52) at 10°33′S 161°03′E / -10.55, 161.05.
I-26’s torpedo set off
Juneau’s magazine, blowing the ship in half; only ten of the ship's 650-man crew were ultimately rescued, not including the five Sullivan brothers.[5]
On the night of 25–26 October 1944, in the aftermath of the Battle off Samar,
I-26 attacked
USS Petrof Bay (CVE-80) off Leyte. I-26 was sunk by either USS Coolbaugh (DE-217) or USS Richard M. Rowell (DE-403).