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In this second segment, we will continue our discussion on Cold War Submarines by exploring NARA records that can be utilized to research the developmental shift from diesel-electric boats to nuclear fast-attack submarines with the modern,  more hydrodynamic, "tear-drop" shape. We will also address what series relate to  operational records for this period, and alternative repositories where further research can be done outside of the National Archives. (Part III of this series, to be published next quarter, will discuss records about the development and available operational and command records to the Fleet Ballistic Missile (FBM) submarines.)


To understand how modern submarines evolved from World War II boats, one needs to revisit the end of World War II and the German and Japanese innovations to their Type XXI and I-200 submarines. For all technical purposes, the submarines of World War I, World War II, and the GUPPYs of the early Cold War were submersibles, but not true submarines. Running on diesel engines, the earlier boats were faster and could maintain a higher speed longer on the surface as compared to their differentially slower speed when using battery power while submerged. They were also heavily dependent on surfacing to renew the air supply in the boat and to recharge the batteries. The post-war innovations from Germany and Japan improved these situations, but did not solve the slow and cumbersome speed underwater. 


The U.S. Navy first improved the hull design to make American submarines better swimmers. The first steps in the GUPPY program was to  remove the extraneous objects that created drag, including deck guns, open periscope shears, and broad decking. The early GUPPY conversions, which included the Tang-Class submarines, maintained the World War II-era submarine shape, which had its problems, such as drag, trapped air bubbles, and cavitation (the collapsing of air bubbles making noise).  Thus, designers revisited the Type XXI design, and developed a “tear top” or blimp shape hull. This new structure had no prominent decking. From the conning tower, - or sail* - of the submarine, it tapered off into a rounded conical shape. The bow was more bulbous, whereas the aft tapered down a single propeller shaft. The other significant change was a single hull design instead of a double.  [Double hull designs have the ballast tanks on the outside of the submarine superstructure, making a second hull. Single hull designs, however, have ballast tanks on the inside of the primary hull structure.] The result was a hydrodynamic hull that was more efficient underwater than on the surface.


* [Terminology NOTE: During World War II, submarines had a command and control work area inside the large dorsal fin. The bridge and periscopes in this area was called the Conning Tower. Post-war improvements moved the command and control area below decks, and it was called the Control Room.  The now empty dorsal fin structure that included the bridge and periscopes became known as the sail.]


The “tear-drop” shape led to two other significant changes.  The large “drop” bow now housed a large spherical SONAR hydrophone array. Older submarines with hydrophones installed on the bottom of the vessel could only scan forward and aft; the spherical hydrophone allowed the sub to be more multi-directional.  With the SONAR array in the bow, this forced the forward torpedo room to be shifted to midship. The other advantage to the “tear-drop” shape was more effective management of water pressure. Combined with advances in metallurgy, these innovations produced submarines with greater operating depths than their World War II counterparts.  


The next major change to construction involved the power plant of the submarine. From 1912 to 1956, the primary propulsion of a submarine was the diesel-electric drive. As effective as these submarines were, their critical flaw was their limited speed and time submerged. Prior to the German and Japanese innovations to battery storage, most submarines could move at 2-3 knots for several hours or as high as 8-9 knots for an hour before the batteries would drain. Following their innovations, the speed increased as high as 20 knots, but still could not be maintained for more than an hour. The batteries also presented safety concerns due to their large, lead acid cells that had the potential to emit unstable hydrogen gas through electrolysis, or deadly chlorine gas if introduced to saltwater. The Navy sought to create a safer vessel, as well as to develop a true submarine that could operate submerged for indefinite periods of time. At the end of World War II, the dawn of the nuclear age offered the promise of unlimited power. The primary concern involved containing the awesome potential of atomic energy in a safe and sustainable power plant. 


The desire for a self-contained portable nuclear reactor that could be fitted aboard a submarine emerged as early as 1946.  Admiral Hyman Rickover, then a Captain, was placed in charge of the nuclear program under the Bureau of Ships to develop safe, ship-sized nuclear reactors. The program produced a reactor that could operate more than just propulsion. It also powered air exchangers and other electrical systems for a seemingless unlimited amount of time.  His project created the USS Nautilus (SSN 571), the first nuclear submarine, in September 1954. The Nautilus, though carrying a nuclear reactor, still looked like a diesel-electric GUPPY submarine with a flat deck and low freeboard. This design was maintained in the next few experimental boats, such as the USS Seawolf (SSN 575) and the Skate-class (SSN 578-579 and SSN 583-584).  The first fast-attack submarine class to combine the “tear-drop” shape with a nuclear reactor was the Skipjack-class (SSN 585-SSN 592) in 1959. From the Thresher/Permit-class commissioned in 1961 to the Los Angeles-class commissioned in 1976, there were new innovations introduced that made each new class of fast-attack submarine quieter, more efficient, deeper diving, and deadlier hunter-killers.


The fate of diesel-electric boats was sealed in 1956 when Chief of Naval Operations, Admiral Arleigh A. Burke announced that the US Navy was no longer going to invest in the development of diesel-electric boats and focusing instead on nuclear-powered submarines. This made the Tang-Class subs, the Sailfish-Class of RADAR Picket subs, the USS Grayback Guided-missile sub, and the “tear-top” shaped Barbel-Class subs built between 1949 and 1957, the last of the diesel-electric sub of the United States Navy.  Although they stopped building diesel-electric submarines, many remained in service for several decades. The last of the Barbel-class were decommissioned in the 1990’s.


Researching the material aspects of the last diesel-electric boats and the early nuclear sub is similar to the procedures discussed in Part I of this series. In Record Group 19: Records of the Bureau of Ships, there are several relevant series. . They include correspondence arranged according to the 5th Edition of the Navy Filing Manual (1950) and - for a brief period in 1960 and 1961 - the current Standard Subject Identification Code (SSIC) filing manual, which was introduced in 1960. 


There is a disruption in the continuity of the Unclassified Correspondence between 1962 and 1965. The Navy began to index the correspondence and no longer arranged it by the SSIC filing system. The indexing was not intuitive and did not follow a pattern that would allow a researcher to pinpoint specific records.  Additionally, the index for this series was determined to be a temporary record and disposed, .Ultimately, the 1962, 1963 and 1964 Unclassified Correspondence were also determined as disposable, because they were not easily accessible.  The 1965 Unclassified Correspondence was retained, and contains  differences in the filing systems. There are some gaps in correspondence in higher classifications, but not as many as during the mid-1960’s for the Unclassified Correspondence.


Unclassified General Correspondence: 1954, 1955, 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1965

Confidential General Correspondence: 1954, 1955, 1956, 1957, 1958, 1959, 1960, (1960-62), 1961, 1962

Secret General Correspondence: (1947-1966), 1954, 1955, 1956, 1957, 1958, 1959, 1960, 1961, 1962, 1964


[Please NOTE: As you review the various Catalog entries on these topics that the entries mentioned in this blog may be still classified for various reasons including for containing Restricted Data (RD) and Formerly Restricted Data (FRD).  Please check the “Access Restriction(s)” section of each of the Catalog entries and that if you are interested in these records that you should follow the guidance on filing a Freedom of Information Act request]


In using correspondence from the 1950s to 1961, you can use similar methods as those described in Part I.  However, you should note the additional designation prefix “SSN” for nuclear submarine, or “fast-attack” submarine.


In addition to the general correspondence series, there are specific series on particular submarines, submarine classes, and submarine systems. For example, there are series on the Nautilus and Skate-class submarines: Correspondence for USS Nautilus , Nuclear Power Plant Diagrams, and Test Reports, 1953 - 1958; Technical Manuals and Related Records for SSN 571-578 part of [Central Correspondence Enclosures]; and U.S.S. Skate (SSN 578) Report of Patrol Number One (Entry UD-WW 39 - No NAID).  Series exist on hull forms, construction, and other systems: Central Correspondence Enclosures 1945-1965; Submarine Reports, 1929-1965; and General Correspondence Relating to Submarine Sonar Systems, 1956 - 1965.  [A note on Submarine Reports (UD 1022-W2): the title is misleading and does not include “patrol” reports, but reports on various ship constructions, hull forms, and machinery arrangement of submarines and other types of ships.]


We also have records on the other two classes constructed during the later period of the Bureau of Ships: the Skipjack-Class (SSN 585-SSN 592) and Permit/Thresher-Class (SSN 593-596; SSN 603-607; SSN 612-615; SSN 621). Most of the information and records on these classes are covered in the Correspondence.


The Bureau of Ships records in Record Group 19 ended in 1966 when the bureau was reorganized into the Naval Sea Systems Command (Record Group 344).


The Unclassified Correspondence of both the Naval Sea Systems Command and the Naval Ship Engineering Center (NAVSEC) are divided into incoming and outgoing correspondence. They are not arranged by Navy Filing Manual or the Standard Subject Identification Code (SSIC).  The incoming correspondence is arranged by the date of correspondence. The outgoing correspondence uses the category system that was developed by the Bureau of Ships in the early 1960’s, as reflected in the 1965 correspondence. It is arranged using these letter categories A, C, D, E-R, N, and S, SS, Y, and then arranged by date. There is a rudimentary relationship between the category letter and the correspondence about a type of ship. For example, the majority of material on submarines should be in the “S, SS, Y” segment. “SS” covers all submarine topics including nuclear fast-attack (SSN) and nuclear ballistic missile (SSBN) subs, as well as conventional boats (SS). However, because of the generalized category system and correspondence being arranged by date, it may be challenging to determine if there is correspondence about the particular boat you are interested in. It is important to note that there may be a minority of correspondence spread out across the other categories about subs, depending upon how the correspondence was categorized.


Because there is not a key to the category designations in these series that were used by the Bureau of Ships and the Naval Sea Systems Command, the National Archives cannot properly navigate these records and advise the public where there is specific information on shipyards, private companies, or shipborne systems.


Unclassified Correspondence (Incoming)

1968, 1969, 1970, 1971


Unclassified Correspondence (Outgoing)

1966, 1968, 1969, 1970, 1971


Unclassified Serial Correspondence Files of the Naval Ship Engineering Center (NAVSEC) (Incoming)

1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976


Unclassified Serial Correspondence Files of the Naval Ship Engineering Center (NAVSEC) (Outgoing)

1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977


Central and Contract Records Branch Ships

Official Subject Files, 1967


In NAVSEA records, there are some series on specific classes of submarines as well as series that cover a broad period of time.  One series covering several classes is Nuclear Powered Attack Submarine (SSN) Maintenance Case Files [Maintce Day C79 C84], Secret Subject Files, 1966-1970 and Ship Design Project Files, 1969-1974


The two main classes of fast-attack submarines developed during the period of NAVSEA are the Sturgeon-class (SSN 637-639; SSN 646-653; SSN 660-687) and the Los Angeles-class (SSN 688-725; SSN 750-773).


Here is a select list of series related to Sturgeon-Class:


Sturgeon Class (SSN 637) and USS Glenard P. Lipscomb (SSN-585) Nuclear Powered Attack Submarine Project Files [CORRES C84]


Sturgeon Class Nuclear Powered Attack Submarine (SSN 637) Project Files [SUBM CASE FILES C84   73]


Overhaul Correspondence Files for Sturgeon Class Nuclear-Powered Fast Attack Submarines (SSN 637)


And here is a select list of series related to Los Angeles-Class:


Los Angeles-class Nuclear-Powered Fast Attack Submarine (SSN 688) Hull and Weapons Development Files [Hull and Weapons Branch, Submarine Ship Acquisition Project Management Office, Fast Attack Class (SSN699) Submarine Design and Technical Files]


Los Angeles-class Nuclear-Powered Fast Attack Submarine (SSN 688) Development Files [Submarine Directorate (NAVSEA 92), Attack Submarine Acquisition Project (PMS 393)]


Correspondence Regarding all Phases of the Construction and Delivery of Los Angeles-class Nuclear-Powered Fast Attack Submarine (SSN-688)


Los Angeles Class Nuclear Powered Attack Submarine (SSN 688) Design Studies and Task Descriptions [SEA PMS 393 Ship Case Files]


Submarine Files [ SSN-688 Class Project Files;  {SHIPS PMS393 SHIP CASE FILE C81/83 75}]


Operational records of submarines during this period can appear confusing. As previously mentioned, Record Group 313 is a good resource for submarine records at the National Archives. After 1954, however, series of theater commands, theater submarine forces, and some individual submarine commands are inconsistent in continuity. There are discontinuous periods of record with gaps. Additionally, for the more recently accessioned records, regardless of their actual classification, will be held as classified records awaiting a second review before being released. In short, like with the Bureau of Ships and Naval Sea Systems Command records, even though series appear in the Catalog, they may not be immediately available, so check the “Access Restriction(s)” section of the Catalog entry for availability.   For those familiar with them, there is a portion of RG 313 defined by Red and Blue Folder numbers. The colors and numbers pertain to a particular series of administrative records from a specific command. There is usually a dossier file associated with the color/number folder, which could be a general container list of Navy Filing Designations or a specific folder list. These records are generally dated through1961. There have been recent accessions, but many are classified, and the accessioning paperwork is not very descriptive. The series COMSUBPAC Primary Program records, 1968-76, which one might think would contain valuable operational records for Vietnam era submarines, only has general administration records (SSIC 5000-5999) and ships material correspondence (SSIC 9000-9999). It does not appear to include any operational records (SSIC 3000-3999 specifically SSIC 3800: Submarine Patrol Reports). 


Record Group 313 is still open and the National Archives is receiving a new series of records for different naval commands including submarine commands. Being new arrivals, it will be some time before series get declassified (if that is necessary), processed and described.  As information becomes available for newly received records of submarine commands, we will update this portion with new information on these series.


In Record Group 38, Records of the Chief of Naval Operations, the Entry UD-UP 11-B (Records Regarding Pacific Area Naval and Fleet Operations, 1966-1970) contains monthly reports from the Commander-in-Chief, Pacific Fleet, reports on Operation Market Time, and submarine surveillance reports of Soviet and Chinese shipping in the South China Sea and the Gulf of Tonkin.  However, the brief reports contain more information about the foreign shipping traffic than the American submarines making the reports.


RG 38 also includes Entry UD-09D 24: Post-1946 Submarine Patrol Reports. As mentioned in Part I, this series contains submarine patrol reports dated through 1958. The reports are mainly from the diesel-electric submarines (SS), with a few from missions to the Arctic by early nuclear submarines like the Nautilus and Skate. However this series is incomplete for the remaining years of the Cold War, and does not contain reports on the numerous patrols made by diesel-electric and nuclear fast-attack submarines. Unlike the World War II and the Korean War patrol reports, there is not a set of patrol reports for the rest of the Cold War and the Vietnam War.  

You may use the NARA Catalog to search for “submarine” topics by refining your search to RG 38 or RG 313 and “series.” If you have further questions about searching the Catalog, email


For Command Operational Reports, Command Histories, Patrol Reports, and other records held outside of the National Archives, the Naval History and Heritage Command is a repository for Cold War and Vietnam War era submarine records.  Command Operational Reports (COR) and Command Histories are annual reports of the ship’s activity. These reports were established in 1964 and maintained through the rest of the Cold War. There were some earlier command histories, but prior to the escalation to the Vietnam War in 1964, regular reporting was not required. The command histories and COR list the location and activities of the ship or sub throughout the year. However, apart from stating the beginning and ending ports and dates for the patrolhe histories, they do not disclose where and what the submarine was doing while on the actual patrol.


There are select patrol reports in the Naval History and Heritage Command’s Vietnam Command Files. These include: the USS Bashaw (LPSS 241) July 1967 report, USS Perch (LPSS 313) in Operation Dagger Thrust IV in December 1965 USS Pickerel (SS 524) January 1967 report, USS Sabalo (SS 302) report on operations for 1969 to 1971, USS Salmon (SS/AGSS 573) reports on operations in 1966 and 1969, and a report from Submarine Flotilla Seven.

For further questions on records on Cold War Submarines in the post-Korean War period, you may contact the Naval History and Heritage Command:


Operational Archives

Naval History and Heritage Command

805 Kidder Breese Street SE

Washington Navy Yard, DC 20374-5060

(202) 433-3224; Fax (202) 433-2833


At the conclusion of World War II, the political landscape shifted from suppression of aggressive fascist regimes to the threat of Soviet communist influence over war torn Allied occupied countries, and territories still under colonial rule calling for liberation. As the United States and the Soviet Union began to square off on land, a larger, more unseen conflict developed under the surface of the ocean.  Similar to both world wars, the US primarily defended against foreign invasion at sea, and the Soviets made ample preparations for confrontation. They armed themselves with newly acquired technologies from the defeated Germans, and began to assemble a large navy with primary investments in undersea warfare. Submarine forces on both sides were near war footing for most of the Cold War, consisting of  quieter and more imperceptible ships, armed with deadlier weapons as part of the booming nuclear deterrence.


This is the first installment of a four part series on the records of Cold War Submarines. It will describe the period from 1946 to 1958, from which there are many records available for research. The second part will discuss nuclear age records of US fast-attack submarines (SSNs) and the height of the Cold War, and the recordkeeping issues with this period. The third part will discuss the development of the Fleet Ballistic Missile submarine (SSBN) and currently available records. The final portion will discuss submarine deck logs for the whole Cold War and the changing landscape of available information.


This chapter of submarine history has two distinctive periods with very different availability of records. Unfortunately, there is no one year when the line is drawn, so there may be some overlap depending on the record group, entry, or government agency.


From the end of World War II to about the mid-1950’s, the US evaluated the successes of their Pacific submarine campaign and their Atlantic Anti-submarine campaign to prepare for future conflicts. They experimented in the creation of various submarine types, including troop transports (ASSP/LPSS), fuel tankers (SSO), RADAR picket (SSR), and guided-missile submarines (SSG). These experimental developments were drawn in part from wartime experiences. They also studied innovations in submarine technology developed by the defeated Germans and Japanese.


By the end of World War II, both Germany and Japan made great strides in developing better submarines that were faster submerged, had more combat capabilities, and were harder to detect even with newer SONAR systems. The Germans developed a snorkel, which enabled their submarines to use diesel engines at periscope depth, giving them greater speed than their American or British counterparts.  The Germans and Japanese experimented with larger battery wells and newer hydrodynamic hull designs to allow submarines to move more efficiently underwater and dive deeper.  They also both experimented with sound absorbing coatings to make submarines less detectable by absorbing active SONAR waves. The Germans developed more sensitive passive SONAR equipment that could hear targets or threats at greater distances. The Japanese developed huge aircraft carrying submarines that had the potential to carry out stealthy air raids.  The most important innovations included the Germans Type XXI and the Japanese I-200 (Sen Taka) submarines. These became the basis for future designs during the Cold War. They were distinguished by enhanced hydrodynamic hulls that were quieter, deeper diving, and capable of tracking potential targets or threats at greater distances, which made the anti-submarine warfare (ASW) practices at the time obsolete.


The records of the evaluations of enemy technology can be found in the Naval Technical Mission Reports for Germany and Japan. There are other series related to Tambach Files, captured records on German technological developments in Record Group 38 and in Record Group 242, which include German submarine developments like the snorkel, passive SONAR, and hydrogen peroxide propulsion.


For Japanese submarine technology, there are other reports, specifically from Submarine Squadron 20, who evaluated the Japanese submarines that surrendered in Tokyo Bay. These included the mammoth aircraft carrying I-400’s and the I-14 in the World War II Command Files and the Flag File Screening Documents. Also, the final reports of the Naval Technical Mission to Japan (NTMJ) include an evaluation of Japanese Submarines (S-17) and other submarine systems and ordnance (S-19).


The other large group of records on the Navy’s evaluation of enemy technology can be found in Record Group 19: Records of the Bureau of Ships in correspondence files, which are arranged using the Navy Filing Manual.  The filing designations that would be helpful would be the country designations for Japan and Germany, which are EF30 and EF37 respectively. There is also a filing designation for captured enemy equipment - EF74. The filing designation for correspondence about submarines, in general, is “SS”. In pairing the different filing designations, files on German submarines are under EF30/SS and files on Japanese submarines are under EF37/SS. These files can be found in the General Correspondence, 1940-45 under the EF 30, EF37 and EF74 segment and the SS segment of the series, the Bulky Enclosures to the Bureau of Ships Correspondence and the Confidential Correspondence, 1946.


In the finding aids for general and confidential correspondence from 1940 to 1946, there are several topics relating to submarines that can be researched using the filing designation “SS”.  You can also reverse the filing designation from EF30/SS to SS/EF30.  But to research innovations in propulsion or other submarine systems in the post-war period, you will need to find the corresponding filing designation. For example, correspondence on developments in propulsion are filed under SS/S41-1 (with S41-1 designating main propulsion).  For other ship related developments, check the S-Section of the manual for filing designations for Ship’s Material.


You may find additional materials on the evaluation of enemy submarines prior to 1947 that later contributed to Cold War developments in Record Group 313: Records of Naval Operating Forces. Listed below are potential series in RG 313 for the Commander, Submarine Forces, Atlantic Fleet (COMSUBLANT) and Commander, Submarine Forces, Pacific Fleet (COMSUBPAC) that may have more materials on the evaluation of enemy submarine technology. 



A1 275 Organizational, Operational, Instructional, and Communication Records

UD 1278 Confidential and Unclassified General Administrative Files

UD 2064 Secret General Administrative Files



UD 2015 Secret Serial Files

UD 1274 Secret Serial Files

P 53 Secret Serial Files

P 57 Top Secret General Administrative Files

A1 222 Confidential, Restricted, and Unclassified General Administrative Files

P 58 Confidential General Administrative Files

P 49 Confidential, Restricted, and Unclassified Administrative Files 

P 46 Confidential, Unclassified & Restricted General Administrative Files

UD 2041 Secret Correspondence Files


These files may contain valuable information, because the Navy relied on the opinions and practical experience of the submarine personnel who had been at sea, in addition to the naval architects and engineers from the Bureau of Ships. In COMSUBLANT, Submarine Squadrons 6 and 10 helped evaluate captured German U-Boats like the Type XXIs, U-2513 and U-3008. On the Pacific side, for COMSUBPAC, Submarine Squadrons 13 and 20 helped evaluate captured Japanese submarines.  Submarine Squadron 13 evaluated the Japanese I-200s (Sen Taka), the Japanese equivalent to a German Type XXI with a streamline hull and larger battery capacity for greater speed and longer endurance submerged. Submarine Squadron 20 helped evaluate the monstrous aircraft carrying I-400s (Sen Toku) that carried three high-speed armed float planes.


As the United States evaluated innovations from captured enemy submarines, the Soviet Union also evaluated captured German submarine technology. The Soviets wanted to make immediate use of this new technology and planned to expand their Navy to include a large submarine arm.  The Soviet submarine force became equipped with hundreds of German Type XXI copied subs that would become the Zulu, Romeo, and Whiskey-classes of attack submarines.  The prospective threat of a large Russian submarine force convinced the NATO navies to rethink their anti-submarine strategies. The US Navy assessed that the Soviet submarine threat was so great that all service arms needed to be included in the new anti-submarine effort. To this end, the US Navy wanted to utilize existing submarines and developed a new class of ASW Hunter-Killer submarines (SSK) to be completed by 1955.


Therefore, the US Navy updated existing World War II-era submarines with German and Japanese wartime innovations. This program was called the Greater Underwater Propulsion Power or GUPPY.  The GUPPY program gave US subs increased underwater speed, endurance, and stealth, which were all necessary for the SSK goal.  However, to be a good hunter-killer, these vessels needed to be able to both locate and attack their quarry sailing at depth. During the same period, the US Navy experimented with copies of the German Gruppenhorchgerät (GHG) passive SONAR set to locate possible enemy submarines. During the late 1940’s and 1950’s, the US Navy tested passive SONAR sets and how to use them during Project Kayo. The goals of the project were two-fold: to make recommendations for the new Hunter-Killers, and to create a manual for existing GUPPY converted World War II-era submarines to follow in the meantime, until the new SSKs come online. 


Correspondence in Record Group 19: Records of the Bureau of Ships, 1940-1966 includes a series of records for each year. To find information on these programs, use the filing designation of “SS” for general submarines and SS### for any specific submarine.  If you are looking for information on specific classes of submarines like the Tang-class or the Hunter Killers, look under SS563-Class or SSK1-Class. These were the first purposely built GUPPY submarines.  The boats of the Tang-class were numbered SS563 to SS568.


Unclassified General Correspondence: 1947, 1948, 1949, 1950, 1951, 1952, 1953, 1954 and 1955

Confidential General Correspondence: 1947, 1948, 1949, 1950, 1951, 1952, 1953, 1954, and 1955

Secret General Correspondence: 1947, 1948, 1949, 1950, 1951, 1952, 1953, 1954, and 1955


[Please note that with Confidential and Secret General Correspondence series in later periods, there may be more restricted classified records that you may need to request under the Freedom of Information Act.]


Record Group 19 also includes several non-correspondence series that relate to submarine development during the Early Cold War Period. These include Entry P 37: Preliminary Design Books, 1904 - 1957, Entry P 62: Records Related to Ship Hull Design, 1940 - 1966, and Entry P 13: Submarine General Information Books and Related Documentation , 1913 - 1961. Another series exists in Record Group 344: Records of Naval Sea Systems Command, Entry P 11-D: Ship Information Books and Related Documentation - Submarines, 1914 - 1978.


In addition to the SSK Hunter Killer Submarines, the Navy began to upgrade and develop submarines for different missions like the Submarine Transport (SSP), Submarine RADAR Picket (SSR), Submarine Fleet Oiler (SSO), and Submarine Guided Missile (SSG). The USS Perch (ASSP 313) and USS Lionfish (ASSP 315) were developed into submarine transports.  The Navy modified each boat under the GUPPY program.  They removed the torpedo tubes to make room for troops. They added a watertight container aft of the sail to hold equipment which was large enough to house an amphibious tractor. The USS Guavina (ASSO 362) was refitted into an oiler. Several submarines were converted into RADAR pickets, including USS Burrfish (SSR 312) and USS Rasher (SSR 269). Starting in 1946, they were converted under the Migraine programs I to III so that the aft torpedo rooms were removed to expand the Combat Information Centers (CICs) and add new RADAR equipment. You may find records on the development of these offshoots and the guided missile submarine (SSG) in the correspondence files in Record Group 19. With the exception of the transport submarines, these experimental variations had limited service lives as new technologies made them obsolete.


On the topic of guided missile submarines, the US Navy first fired small rockets at shore establishments during World War II when the USS Barb (SS 220) attacked Japanese facilities. This led to developing the first guided missile submarine (SSG), borrowing the German’s V-1 “Buzz Bomb,” and Japanese innovations of watertight above deck storage compartments.  Project Loon began in the late 1940’s. These programs led to Projects Regulus and Regulus II, which were built on the same concept but improved the missile and changed the warhead from conventional to nuclear. In Record Group 72: Records of the Bureau of Aeronautics are the chapters and background notes to Admiral D. S. Fahrney’s History of Pilotless Aircraft and Guided Missiles.


The National Archives in College Park also maintains operational records for submarines during the Early Cold War. In particular, the Korean Conflict was an example of the pivot from World War II’s unrestricted global submarine warfare to a maritime policy of limited regional war. At the outset of the Korean Conflict in June 1950, the US and the Western Allies were anxious that the conflict was just the opening act to World War III. The few submarines based in Japan and Pearl Harbor were rigged with a full war load of torpedoes and deployed to the waters neighboring Korea to look for Soviet ships.  Unlike in World War II, the submarines of the Far East Command were instructed to observe and await further orders. What concerned the US Navy was the 50 to 60 reported submarines in Vladivostok, Russia. As the conflict continued, the mission for US submarines became the surveillance of Soviet and Chinese shipping in the East China Sea and the Sea of Japan.


These reports, as well as other pre-Korean and post-Korean Conflict submarine reports can be found in Record Group 38 in the post-1946 Submarine Patrol Reports. This collection of post-World War II patrol reports include operational reports for US submarines during the period of the evaluation of enemy technology. It includes US utilization of that technology in new types of classes (1946-1950), the Korean Conflict (1950-54), and some post-Korean patrols (1954-59).  The series includes reports of diesel-electric submarines (SS) with a few reports from early nuclear submarines (SSN) and one endorsement for a nuclear ballistic submarine (SSBN).  This is not the main body of records for nuclear fast-attack or ballistic submarines, but this will be discussed in the next installment.


Another source of operational records during the Korean Conflict and continuing through 1958-59 are in Record Group 313. In addition to the submarine commands, there may be other files relating to submarine missions under other types of commands, depending on the mission.  For example, there are training reports of US Marines and the Royal Marine Commandos aboard the USS Perch (ASSP 313) prior to and during the early part of the Korean Conflict in the Commander, Amphibious Forces, Pacific. There may be additional  records under other commands, like fleets or service forces.


This concludes the first part of this topic. The next segment will discuss the records of the Cold War Submarines from 1954 to 1992 with the advent of nuclear power and the development of fast-attack submarines (SSNs), and the problems that arise with pertinent records.


One interesting topic that people like to research is the period between the World Wars, and how the United States evolved from an equal ally of Western Europe at the end of World War I to the Arsenal of Democracy in World War II. The U.S. Navy is a great example of how world events contracted and inflated the service as it was struggling to meet the demands of restrictive naval limitation treaties, while also protecting the United States and its far flung territories across the Atlantic and Pacific as an emerging global maritime power. Emerging from the Great War with budget cuts and surplus vessels, the Navy entered a period of innovation characterized by the development of new technology balanced by a “make do” mentality. They experimented with primitive aircraft carriers and early naval aircraft and made improvements on submarines, the definitive weapons of the next war.


The Office of the Secretary of the Navy was also influential in the management and protection of United States territorial holdings like Puerto Rico, the Virgin Islands in the Atlantic, and Guam, Midway, Hawaiian Islands, and the Philippines in the Pacific. While maintaining the uncomfortable balance between budget cuts and the increasing threat of war in both oceans, the Office of the Secretary of the Navy shifted priorities from the build up of naval bases in these remote bases to planning the logistical framework of the next war.


A great resource for beginning research on the interwar U.S. Navy is with the General Correspondence of the Secretary of the Navy. The general correspondence includes letters, memoranda, and other reports from different parts of the Navy, including the assistant secretaries of the Navy, bureau heads, the Chief of Naval Operations, and the Judge Advocate General. The correspondence also includes letters to and from other parts of the government, including President Franklin D. Roosevelt and the U.S. Army.


The best starting point for accessing the correspondence is M1067: Name and Subject Index to the General Correspondence of the Office of the Secretary of the Navy, 1930-42. This series of index cards was originally microfilmed and made available in the microfilm room at the National Archives in Washington, DC. The microfilm has now been digitized and is available in the National Archives Catalog. This series consists of 187 rolls of microfilm listing names and subjects alphabetically. Each card relates to a name or subject, has a brief line about the letter, the date of the letter, and the Navy Filing Manual designation it is filed under.


Once you have the dates and Filing Manual designations from the microfilm series, you can use this information to search through the two general correspondence series: the General Files, 1926-40, or the General Correspondence, 1940-42. Both series are arranged according to the Navy Filing Manual.


Please note, the General Files series starts in 1926, but the index does not start until 1930. The Office of the Secretary of the Navy believed there would be no reason to index the correspondence following the publication of the Navy Filing Manual in 1925. By 1930, however, the Office had more correspondence than could be navigated with just the filing manual, and thus created an index. The division of the two series in 1940 corresponds to the beginning of World War II.


The two general correspondence series contains correspondence of the Office of the Secretary of the Navy at the unclassified and restricted levels. Even at these lower classification levels, there is a broad span of topics regarding the interwar period, ranging from new constructions to planning policies. There are also cards about companies and individuals that helped build up the fleet in the period before the war. The cards also include topics related to gender and race topics including developing policies on women and African Americans serving in the Navy or in the Naval Reserve. There are many interesting gems in these records such as the expansion of the U.S. Navy through the planned, appropriated, and constructed new ships before December 1941 at different naval shipyards. There are copies of the 1940 appropriation bill, better known as the “Two-Ocean Navy” bill or the Vinson-Walsh Act, which lists all the new ships of the expanding Navy that would later impact the outcome of the Second World War.


For those interested in the events in the Pacific Theater and the developments of advanced bases, there are index cards for islands including Midway, Wake, and the Hawaiian Islands, and what was being planned for the Asiatic Fleet based in the Philippines. There are also several cards regarding war plans and fleet exercises.


In addition to the General Correspondence of the Office of the Secretary of the Navy, there are also the Formerly Confidential and Secret Correspondence series of the Office of Secretary of the Navy. The 1927 to 1939 portion of the Formerly Confidential and Secret Correspondence share a single index. Although this index has not been digitized, it is similar in nature to M1067 in that it consists of name and subject index cards arranged alphabetically by topic. It is arranged in four parts: incoming correspondence, name and subject index, and outgoing correspondence are arranged alphabetically; and a second name and subject index is arranged according to  Navy Filing Manual designations. The name and subject portion of the index lists the topic and what correspondence is associated with it, what classification the correspondence is under, and what Navy Filing Manual designation it was given. Certainly, you can experiment with the Navy Filing Manual portion for the index too, and see what kinds of materials are under a particular Filing Manual designation.


The Formerly Confidential and Secret Correspondence are divided into two different series. Both series are arranged by the Navy Filing Manual. Since these correspondence series had been classified at a higher level, they should include more details on particular topics than the General Correspondence.


The Formerly Confidential and Secret Correspondence and indices for 1940 to 1947 dovetail to the earlier series.


The index to the later Formerly Security Classified Correspondence of the Secretary of the Navy and Chief of Naval Operations, 1940-47, is divided into several sub-sections by year blocks. Under each subsection, the index cards are divided into groups of incoming, outgoing, alphabetical by topic, and the Navy Filing Manual. The Formerly Security Classified Correspondence is divided into year blocks, then arranged by classification level, and then according to the Navy Filing Manual. You can explore the different formerly classified correspondence series by either using their respective index or utilizing the Navy Filing Manual designations.


In addition to the other correspondence series, the index and the general correspondence overlap with other microfilm collections of the Fleet Problems and the Records of the World Crisis, which have been discussion topics on the History Hub.


The correspondence series of the Office of the Secretary of the Navy from the interwar period to the early years of World War II illustrate the ebb and flow of national and naval policies in regards to international naval treaties, the shift from limiting naval construction to mass production into the expansion of the “Two Ocean Navy”, and from tentative budgeting for naval outposts to a mad rush to re-enforce them as the situation began to turn towards general war.


For information on the Index and the General Correspondence of the Office of the Secretary of the Navy, 1930-1942 and the Index and Formerly Confidential and Secret Correspondence of the Secretary of the Navy, 1927-39, please contact For questions about the Index and Formerly Security Classified Correspondence of the Secretary of the Navy, 1940-47, please contact


From a historian’s perspective, it’s easy to see how the stresses and strains between nations lead to the outbreak of war. But what about at the time? What was known? What was missed? President Franklin D. Roosevelt wanted answers to these questions, but who could he ask? Who were the proverbial weathermen that could forecast the typhoons that hurled the world into chaos?


President Roosevelt turned to Secretary of the Navy Frank Knox for answers. Roosevelt asked Knox to gather all the naval attaché reports and dispatches from key foreign cities going back to January 1937. He wanted the search to include reports and dispatches from London, Paris, Brussels, Rome, Berlin, Moscow, and Tokyo. The President asked for reports from Bulgaria and Austria too, but there were not any naval attachés there during the specified period.


The reports and dispatches were compiled into a series of records, which was later microfilmed as National Archives Publication M975: Selected Naval Attaché Reports Relating to the World Crisis, 1937-1943. It is a small three-reel collection.


The documents that were microfilmed are stamped with various classification markings from Secret to Restricted. These documents have been declassified under declassification authority - DECLASSIFIED, E.O. 11652, Sec. 3(E) and 5(D) or (E), NND 730043, and researchers may make copies of the documents.


The reports are arranged in two subseries: “Estimate of Potential Military Strength” and “Probability of an Outbreak of War.” They are further arranged by post of attaché, and thereunder chronologically and numbered consecutively. Letter symbols have been employed to identify the post from which the reports originated. The symbols used for the “Estimate of Potential Military Strength” are:


  1. London
  2. Paris
  3. Brussels
  4. Rome
  5. Berlin
  6. Moscow
  7. Tokyo

The symbols used for the “Probability of an Outbreak of War” subseries are:

  1. London
  2. Paris
  3. Brussels
  4. Rome
  5. Berlin
  6. Moscow
  7. Tokyo


There are several volumes of reports and dispatches for each city.


Preceding each group is a summary that includes excerpts and abstracts of the reports with letter and number notes written in the margins, which correspond to the report or dispatch that it was taken from. For example, K-2-77 indicates the 77th Report in the 2nd Volume from Rome (K) from the subseries “Probability of an Outbreak of War.” There is sometimes a number in parentheses indicating a page number from a report.


The information discussed in the reports varies from post to post. For example, the Berlin reports include U-Boat development and the success of overtaking parts of Czechoslovakia, the London reports cover the expansion of British Forces and preparations for shifting of power in Europe, and the Tokyo reports include strategic Japanese plans for China and the expansion of the Japanese military and naval forces.


These reports were a selection made by Secretary Knox, but more context can be found through further research. Record Group 38: Records of the Chief of Naval Operations includes  additional bodies of naval attaché intelligence reports both at the National Archives in Washington, DC (in Entry NM-63 98 for the period of 1900 to 1939) and the National Archives in College Park (in Entries A1 98-A and A1 98-B for the period of 1940 to 1946). The index to the naval attaché files at the National Archives in College Park has been microfilmed in NARA Publication M1332, which also has been digitized, and will be the subject of a future History Hub blog. In addition to the naval attaché reports, there are several series of monograph files relating to Germany, Japan, and other countries. The monograph files are basically the Office of Naval Intelligence’s vertical files, where articles, reports, and other printed material were collected and sorted into subjects like functions of the government, and army and navy of a particular country. Another resource is the two series of administrative files for the Office of Naval Intelligence (Entries UD 84 and A1 85), which have inclusive dates that start before the war, but the bulk dates are the war period. These administrative files are arranged according to the Navy Filing Manual (4th Edition, 1941).


Despite myriad signs, changes in the wind, and the scent of the coming storm, no one was able to predict what would spark World War II. The naval attachés knew about their individual areas, but could only make guesses as to what their future would hold. The storm would not arrive until the first drop of rain and the first rumble of thunder, which was no longer in the distance, but in the here and now.


In the aftermath of World War I with the rise of American global status, a colonial power in the Carribean and Pacific and a component of a European alliance with Great Britain and France, the United States Navy began to take their theories of fleet actions and developed them in practical real world exercises.  These practical exercises were known as the Fleet Problems conducted between 1923 and 1941.  The Fleet Problems were number I to XXI and there was a XXII Problem planned for January 1941, but it was cancelled.  These records were microfilmed into National Archives Publication M964: Records Relating to United States Navy Fleet Problems I to XXII, 1923-1941.


The records contained in this series come from three different record groups: Record Group 38: Records of the Chief of Naval Operations, Record Group 80: Records of the Department of the Navy, and Record Group 313: Records of Naval Operating Forces. In Record Group 38, these series are from Division Fleet Training, Confidential Correspondence, 1927-1941 and Confidential Reports, 1917-1941. In Record Group 80, there are documents from the Secretary of the Navy’s Secret and Confidential Correspondence, 1919-1926 and the Secretary of the Navy’s Confidential Correspondence, 1927-1939. And in Record Group 313, there is the Commander-in-Chief, US Fleet Confidential Correspondence, 1939-1940.


The Fleet components involved in the exercises were the Battle Force and Scouting Force. The Battle Force and Scouting Force were sub-divisions of the US Fleet that was reorganized in 1922. The Battle Force later was reorganized into the Pacific Fleet and the Scouting Force was reorganized into the Atlantic Fleet in 1941.


Each of the exercises were designed to address a specific component or scenario within the context of a “colored” war plan.  The opponents in the exercises were described as “Blue” forces, the United States, and aggressor forces “Black”, Germany, and “Orange”, Japan. The locations of the exercises do not necessarily reflect the hostile forces being tested in that there are a few Fleet Problems staged in the Caribbean simulating fleet actions around Hawaii. In some of the Fleet Problems, the Battle Force and the Scouting Force were pitted against one another, and in other cases a single force was divided into both opponents.


One of the more interesting aspects of the Fleet Problems is how the US Navy was preparing for the next war and how new equipment would be used like aircraft and submarines as well as new tactics like amphibious landings. Another factor that the US Navy was contending with is the possibility of a two-ocean war with a limited fleet that was constricted by the Washington Naval Treaty of 1920-1921.


Many naval historians look to the Fleet Problems as evidence to the axiom of “Generals are always prepared to fight the last war” or in this case “Admirals.”  The general consensus is that the Fleet Problems reinforced the notion that the next naval war would have the battleship as the centerpiece of a fleet at the exclusion of other vessels.  Other vessels like aircraft carriers and submarines were auxiliary to the fleet and would be only used in reconnaissance roles rather than a major projection of naval power.  Although, carrier-based aircraft proved to be very useful in turning the tide in a battle during the Fleet Problems. In the 1930s as a result of the Fleet Problems, the Navy elected to construct more aircraft carriers and expand naval aviation. But the true potential of aircraft carriers within a battle group had yet to be proven and would not until the Second World War.


On aircraft carriers, there were several tests of carrier based aircraft against naval bases such as the Panama Canal and more famously, Fleet Problem XIII in 1932 where the USS Saratoga (CV 3) successfully attacked the Naval Base at Pearl Harbor, HI in a test of the base’s defenses. 


For submarines, their potential as a weapon continued to be misunderstood and mired in world opinion, being compared to German U-boats. and being anchored to fleet reconnaissance. The term “Fleet Submarine” comes from this period when the Navy was trying to have submarines operate with the surface fleet and not be perceived as the lone wolves of the First World War preying on commercial shipping.  But because of the dramatic shift in speed on the surface compared to a submarine’s speed underwater, it was hard for the surface fleet to interact with submarines without planning submarine positions far in advance of the fleet. Another aspect of the Fleet Problems that showed bias against submarines was the criteria during exercises where submarines attacked escorted convoys.  Detection amounted to being successfully attacked and this bred a cautious submariner in the early days of World War II.


There are many related records to this series at the National Archives in Washington, DC and at the National Archives in College Park. 


The National Archives at Washington, DC - Textual Reference (RDT1), which you can email at, has custody of series in Record Group 38: Records of the Chief of Naval Operations, Record Group 80: Records of the Department of the Navy and Record Group 313: Records of Naval Operating Forces.


Specifically in RG 38, there are the correspondence series of the Chief of Naval Operations, arranged by the Navy Filing Manual, that include discussions of fleet development and training as well as war planning prior to 1941.


In RG 80, there are three series of interest: the 1930-42 General Correspondence of the Secretary of the Navy, (the index is on the Catalog), the Records of the General Board, and the Records of the Joint Army-Navy Board. The General Board was an advisory board of retired Fleet Admirals, and the series pertained to innovations in new ships, new tactics, and new strategies. These series have their own filing scheme based on a topic that is different from the Navy Filing Manual. The Joint Board records reviewed war planning and the development of base defense for Army and Navy installations, both domestic and abroad.


In RG 313, there are series of records relating to the individual forces: Battle Force and Scouting Force, and some of their subordinate commands such as commander, submarines and commander, aircraft.


The National Archives at College Park - Textual Reference (RDT2) has custody of only a few series in Record Group 38: Records of the Chief of Naval Operations and Record Group 313: Records of Naval Operating Forces that would relate to the Fleet Problems because the majority of the pre-World War II Navy Records are in the custody of the National Archives at Washington, DC - Textual Reference.


In RG 38, there is a collection of records relating to the Fleet Problems in the records of the Strategic War Plans Division in Entry A1 355. The date range of these records is from 1912 to 1946 and divided up into 12 sub-series.  In particular, Series II: Naval War College Instructional Materials, 1914-1941 and Series IX: Plans, Strategic Studies and Related Correspondence, 1939-1945 have materials related to the Fleet Problems.  In Series II, there are continuations on the fleet exercises and analysis of each of the opponents’ situations. In Series IX is a set of copies of the historical development of the war plans arranged chronologically.  


In RG 313, there is a series of files covering 1940 to 1942 and the transition of Commander-in-Chief, US Fleet (1940), combined with Commander-in-Chief, Pacific Fleet (February 1941), and the two commands being separated in December 1941 following the attack on Pearl Harbor. The series is the General Files and Serials of Commander-in-Chief, Pacific Fleet, 1940-1942. This series fills the gap between the CINCUS files located at the National Archives in Washington, DC and the Commander-in-Chief, US Fleet (renamed COMINCH) Formerly Security-Classified Correspondence, 1942-1945 at the National Archives in College Park, MD. 


To inquire about the availability of related records that were suggested, please contact the National Archives at College Park - Textual Reference (RDT2) via email, If you are interested in ordering a copy, please provide your mailing address and phone number in your request since both are required for the reproduction order form.


To highlight another series that is available on the National Archives Catalog, we are featuring the new scanned series of index cards to the Anti-Submarine Incident Reports from the Anti-Submarine War (ASW) Section of the Records of the 10th Fleet in the Records of the Chief of Naval Operations (Record Group 38). 


Like many records at the National Archives, accessing the ASW Incident Reports has been a two-step process by reviewing the index and then ordering the reports.  The Incident Reports are arranged by report number, which is numeric and does not indicate the target, attacker, or date.  Because of this, the index is the only way to access them.  The index is arranged by the designation of the attacker of the enemy submarines.  On each card for an attacker, the incidents are arranged by date with a report number listed. 


To further explain the arrangement of the index cards, the four small boxes are divided into Ships (A-Z), US Naval Aviation, Non-Navy Aviation (Army, Marine Corps, Coast Guard), Foriegn Aviation, and a few cards on Surrendered Vessels.


The reports themselves are a record of an attack on an enemy submarine usually German U-boats and some Japanese submarines. These reports detail how contact was made, how the attacking unit proceeded to pursue the enemy, the attack itself, and the assumed result of the attack. The purpose of the reports and the collection as a whole was to learn how to improve anti-submarine strategies and tactics by seeing what worked and what did not.


Due to the lack of organization and a central channel for reporting incidents at the beginning of the war, anti-submarine incident reports were not consistent until mid-1942. As the United States entered World War II, America was confronted by a clear and present threat of German and Japanese submarines attacking our supply lines with Great Britain and Australia as well as moving our own troops and equipment to the battle fronts across the sea. Despite this threat, the US  was slow to adopt anti-submarine methods like convoying, securing information on departing ships at ports, and even blacking out coastal cities so as not to silhouette incoming and outgoing ships.  


The first move to addressing the submarine threat was the formation of the Convoy and Routing Division under the Chief of Naval Operations in May 1942.  The Convoy and Routing Division was responsible for routing and protecting merchant shipping in U. S. waters and troopships going abroad. C and R was the forerunner to the 10th Fleet, which was established in May 1943. In the year between the establishment of the two commands, the science of anti-submarine warfare had blossomed with refinements to SONAR, improved depth charges, and forward throwing subsurface weapons called Hedgehogs. Also, there was improvement to aviation with multi-engine aircraft that could take air patrols out further into the U-boat infested waters of the Atlantic and with new Arc lights to illuminate them in the night as they recharged their batteries on the surface following a day’s hunting.


Around April-May 1942, the reporting on anti-submarine activity became more regular and consistent.


The index cards and the ASW Incident Reports also relate to other series in the Records of the Chief of Naval Operations (Record Group 38). The Incident Reports, in some cases, may duplicate what are in the Action Reports and in other cases, they are purely unique. The detail also varies widely from a single page or less description to a multi-page report complete with sketches of the attack. Therefore, if you are researching anti-submarine operations during the war, it is important to review both the Action Reports and the ASW Incident Reports.


These series also relate to other records within the Records of the 10th Fleet such as Convoy Reports and US and Allied Shipping Losses as well as the separate series of Armed Guard Files, which are reports from the US Naval Armed Guard units that served aboard merchant ships to defend them.


Another series of records that have records relating to Anti-Submarine Warfare during World War II are the World War II Command Files.  This series is arranged hierarchically by command and office.  For example, there are ASW bulletins among the files of the Commander-in-Chief, US Fleet (COMINCH/CINCUS); ASW Information (weekly notices) filed with the records of the Atlantic Fleet; and separate sections of records for the offices of the Anti-Submarine Section and the 10th Fleet that were directly related to ASW efforts during the war. There may be other ASW-related materials incorporated into a larger report sent to a higher fleet or regional command such as an island command, sea frontier or naval district.


To inquire about the availability of an Anti-Submarine Incident Report or any of the records suggested, please contact the National Archives at College Park - Textual Reference (RDT2) via email, If you are interested in ordering a copy, please provide your mailing address and phone number in your request, which is required for the reproduction order form.


To continue to highlight new digital series available on the National Archives Catalog, World War II War Diaries, Other Operational Records and Histories, 1942-1946 is another series that has come from NARA’s digital partners. This series includes some war diaries, some action reports, some submarine patrol reports and some battle histories of various naval, Marine, and other Allied commands during World War II. These records were scanned from a microfilm series that the Navy created from select war diaries and other reports.


This series is the first step in researching a Naval and some Marine operations during World War II, but remember this is not a comprehensive series of war diaries and so its title is a little misleading.  If you cannot find a war diary or an operational report for the Naval command you are interested in the digitized war diary series, then please be aware that there are larger textual series of War Diaries, Action and Other Operational Reports, World War II Command Files in the Records of the Chief of Naval Operations (Record Group 38) and the U.S. Marine Corps Operations in World War II (a. k. a. Geographic Files) in the Records of the US Marine Corps (Record Group 127) where you might find what you are looking for. 


One of the interesting tricks to the textual series of war diaries is that there are some command war diaries that have been stamped saying that a certain portion of the war diary has been microfilmed. Those microfilmed portions can be found in this series.  As a follow-up to this statement, please do not assume that in all cases where one series ends the other begins. There are several cases where there is duplication and in others there are exclusively solitary copies of reports - meaning they exist solely in one series and not in the other. 


The duplication of reports in multiple series or the isolation of unique reports in individual series can be said for action and other operational reports.  Again If you cannot find a particular action report or Marine operational report, then you might try to look at the associated textual record series.

If you need to check for the availability of a war diary, action report, or another type of operational report, then please contact the National Archives at College Park - Textual Reference (RDT2) via email, and RDT2 can check their holdings.  If you are interested in getting a copy, then please provide your mailing address and phone number in your request in case RDT2 needs to draft a reproduction order form for you.

In the last few years, the National Archives has been partnering with online services like and 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.