Shortland Islands
"Sturgeon" stood out of port, on 4 September, to begin her fifth war patrol in an area between Mono Island and the Shortland Islands in the Solomon Islands group. On 11 September, she began patrolling west of Bougainville to intercept enemy shipping between Rabaul, Buka, and Faisi. The submarine fired four torpedoes at a large cargo ship, on 14 September, but missed with all.