While the bulk of the collection consists of war patrol reports written during wartime, some prewar patrol reports are included. All of the reports are typed; most are mimeograph copies. Photostat or carbon copies are also found.
The submarine war patrol reports for 1941 through late 1943 consist of daily narrative summaries of the vessel's location and activities. The reports are usually followed by additional summary information relating to such topics as meteorology, physical and mechanical condition of the submarine, and attacks against the enemy. These early reports may relate to a number of other topics as well.
Reports submitted from late 1943 through 1945 are normally much more detailed than the earlier reports, and almost uniformly adhere to a standardized format. The elements of the later reports are below.
Some World War II submarine war patrol reports are appended with special mission or other reports delineating operations separate from the main task of sinking enemy ships. A final feature of most of the war patrol reports is the endorsements added by the various reviewing levels in the chain of command. The endorsements mainly consist of comments, assessments, and commendations.
Occasionally, the war patrol reports include periscope photographs and track charts. Photographs and very oversized charts appended to the reports may not be included in the digitized images here; notes indicating such omissions are included.. Sometimes, the reports list enclosures, usually track charts, which are no longer part of the records. The location of these missing enclosures is unknown. All other extant enclosures, as well as the full patrol reports, are included in this publication.
An informative descriptive pamphlet provided by NARA may be downloaded here. Much of the information on this page is taken directly from that pamphlet.