Patrol Squadron 13 (VP-13) was established on 1 July 1940, formed at Naval Air Station San Diego, California, from personnel from VP-14. Equipped with PB2Y-1 Coronado flying boats, the squadron began flying long surveillance patrols and flights to bases in the Pacific to deliver personnel and supplies. A flag transport detachment was established at NAS Kaneohe Bay, Hawaii.
In April 1942, VP-13 received PB2Y-2 versions and assumed transition training crews destined for other PB2Y squadrons. In June, the squadron received its first PB2Y-3, and in November, the flag detachment was recalled from Kaneohe. However, in January 1943, VP-13 moved as a unit (with 12 PB2Ys) to Kaneohe and began regular patrols around Hawaii and special transport runs.
In December 1943, the PB2Y-1/2 versions were replaced by new PB2Y-3s, four of which were converted to PB2Y-3H ambulance aircraft and sent to the Gilbert Islands.
In January and February 1944, VP-13 and VP-102 aircrews, flying from Midway, carried out four bombing raids against Japanese facilities on Wake Island. In 50 sorties in round trips of 4,200 miles each, the PB2Ys dropped 60 tons of bombs without losing a plane or crewman. The raids were first ever conducted by formations of heavy seaplanes over long distances.
In April 1944, VP-13 crews based on Ebeye laid mines in the waters around Truk, and in May conducted nuisance raids for 11 nights on Wotje, dropping one 500-pound bomb every half-hour for 12 hours each night. During the first half of 1944, VP-13 crews shot down five Japanese Navy G4M “Beatty” bombers.
VP-13 regrouped began receiving PB2Y-5 versions in September 1944. On 1 October 1944, the squadron was redesignated Patrol Bombing Squadron 13 (VPB-13). VPB-13 covered the February 1945 invasion of Iwo Jima, and in April covered the Okinawa campaign from Kerama Rhetto. During operations off Japan and China until the war’s end, VPB-13 crews shot down four more Japanese aircraft, while losing one PB2Y, which ditched following hits from antiaircraft fire.
VPB-13, stationed at Hong Kong shortly after hostilities ended, returned to San Diego in November 1945, and was disestablished on 21 December 1945.