In the last few years, the National Archives has been partnering with online services like Ancestry.com and Fold3.com to digitize microfilm and microfiche series of records. The intent was that after a span of time on these sites, these materials eventually will be made available on our Catalog. One of these series is the World War II Submarine War Patrol Reports, NARA Publication M1752, NAID 305243, and Entry A1 307 in Record Group 38: Records of the Chief of Naval Operations.
This series is arranged by the name of the submarine and then by war patrol number, but through the Catalog, you can “Search Within This Series” and search for any specific submarine.
Please remember, this series only includes reports of assigned war patrols and war patrols that were completed. The majority of the war patrol reports are from submarines assigned to Commander, Submarine Forces, Pacific; Commander, Submarine Forces, Southwest Pacific; and Commander, Submarine Forces, 7th Fleet. If you are looking for periods of training, extra duties outside of a patrol, or when a submarine was lost, then you will need to look in other records in Record Group 38: Records of the Chief of Naval Operations or in Record Group 313: Records of Naval Operating Forces.
At the beginning of World War II, Chief of Naval Operations and Commander-in-Chief, US Fleet decided that submarines operating in the Pacific were not to maintain war diaries like other vessels, but to file report on their assigned war patrols as an equivalent record of activity.
The war patrol reports consist of several sections including a brief summary of events between patrols, which covers training and overhauls, a chronology of patrol, a record of sightings (ships and aircraft), data on torpedo firing, and evaluations of different departments and sections aboard the boat on how equipment and crew performed during the patrol.
These records and this digital collection is helpful to begin any research on World War II Submarine Operations in the Pacific. During the war, submarines were asked to do more than sinking ships. They were asked to drop off or pick up troops like in the Makin Island Raid and the invasion of Adak, rescue downed pilots in lifeguarding missions, photo-reconnaissance missions, evacuating people and material, and to lay mines. Sometimes there were additional reports that were filed, but not included in the war patrol reports. These additional reports can sometimes be found in the World War II Action and Operational Reports, Entry A1 351 in Record Group 38: Records of the Chief of Naval Operations, NAID 305236. The action reports can also include reports on the loss of a submarine, collecting all the available information on when they were last hear from or seen.
There are other series within Record Group 313: Records of Naval Operating Forces under Commander-in-Chief, Pacific Fleet, Commander, Submarine Forces, Pacific and Commander, Submarine Forces, Southwest Pacific. There are several entries for these commands within this record group. These series are the administrative files of these commands and are arranged by or use the Navy Filing Manual (4th Edition, 1941). You can use these files to further develop the background to a mission or what information was gained from a mission.