The Silent Service, Pt 1

Excerpts from The Silent Service: A Submarine History of the Red Navy

…The Submarine Force entered into the Battle of the Atlantic substantially overbuilt for the present adversaries. With a building program tailored to starve the island nation of Great Britain into submission in a campaign of total war, they were a poor fit for the struggle against Germany in 1940 and 41. While the secrecy behind Operation Teutonic ensured that many ships of the German merchant navy would die like lambs in the first month of the war, after the brief feast the sea wolves would enter a famine period.

German and Italian flagged shipping simply disappeared from the Atlantic Ocean. Overseas trade continued under neutral flagged vessels, and the Royal Navy remained the guarantor of freedom of navigation. Unwilling to risk war with Britain as the aggressor, the Chief of Naval Operations set strict rules of engagement prohibiting any engagement without positive identification, and set boundary zones to keep submarines away from the territorial waters of all neutral nations.

The German U-boat fleet fought under similar restrictions in this period, but since the neutral flagged shipping was generally unavailable, especially with the opening of the South American theater of the war, the WFRN was forced to run convoy defense to preserve shipping to the Soviet Union.

[…]

American submariners, trained to cultivate aggressiveness and elan, frequently tested the limits of their rules of engagement. The most numerous boats in the service in 1940, the Gato -class(1), were large “fleet submarines”, refinements of a doctrine developed in the immediate aftermath of the Great War. Like their predecessors, they were fast for submarines, able to do 39 klicks on the surface, and 17 submerged, with an unmatched practical endurance. Able to cruise 20,000 km and sustain 75-day patrols, they also were extremely spacious and comfortable by submarine standards.

Air-conditioning ensured reliability for the electrical systems as well as crew comfort, and the generous freshwater distillation capacity meant that crews could shower and wash their clothes. Refrigeration allowed fresh stores to be kept, keeping crews healthy on long patrols, often extended by rendezvous with submarine tenders.

This long endurance, and the lack of readily available targets resulted in some skippers taking the stalking of Kriegsmarine assets to an absurd level. The most notable case was that of the Nautilus(SS-306), under the command of CDR Obed Ashley*, who shadowed the notorious German supercruiser Admiral Scheer with the tenacity of Ahab hunting Moby Dick, off and on for six months, until finally ambushing the “pocket battleship” outside the Spanish port of Cádiz.

The German raider had been operating out of Cádiz for some time, taking on fuel as well as munitions, in direct violation of the supposed neutrality of the Spanish State. With the Falangist regime still unrecognized and maintaining no formal relations with the UASR, Ashley had just enough wiggle room in his standing orders to take his boat into Spanish territorial waters on the night of 12 February 1941, crawling along for days, waiting for a glimpse of Admiral Scheer ‘s tall tower, crowned with a distinctive stereoscopic rangefinder, exiting the port.

He got his chance on the 19th, just as the sun’s first rays were peeking over the nautical horizon. Running on coffee and fumes after taking a second watch to allow his equally beleaguered XO a chance to rest, Ashley positively identified the Admiral Scheer , cruising out in the main shipping channel, escorted by Spanish destroyer Lepanto. General Quarters was sounded at 0705 local time, as the Nautilus plotted a submerged, flank speed intercept.

It would be close; the nineteen thousand tonne German cruiser was lollygagging its way out of the harbor now, but she could cruise at near to the Nautilus ‘s surface flank speed. And even with the sophisticated fire-control offered by the Torpedo Data Computer, achieving a shooting solution in the short window would be fraught. Worse, striking the Lepanto would cause considerable complications to the war effort.

So while Admiral Scheer and Lepanto steamed south-by-southeast out to the open ocean, Nautilus approached on a north-by-northwest track at periscope depth. After a final adjustment to the shooting solution with active sonar, Ashley ordered the launch of a spread of four Mk 16 torpedoes at 0725 at a range of 2500 metres, near the limit of the effectiveness of her WCA-2 sonar set. The torpedoes all turned onto their gyro track, and ran true.

Even a noisy, hydrophoneless cruiser like the Admiral Scheer rang like a bell below the waterline from Nautilus ‘s sonar pings. But still in Spanish territorial waters, the officer of the watch was slow to react to the threat. It may not have mattered in the end; by the time reports reached the bridge, the torpedoes were already well on their way. The engine telegraph order for full speed was received but never implemented. Three torpedoes, each armed with 440kg of HBX explosives, detonated on or beneath Admiral Scheer’ s hull, with the fourth believed to have run ahead of her bow.

Ashley did not wait to confirm Admiral Scheer ‘s sinking. Once the first hit had been confirmed, he ordered Nautilus as deep as she could safely manage in the shallow water, and began the slow 4 klick crawl out to sea, rigging for silent running.

While additional Spanish State ships would sortie to hunt for Nautilus , Lepanto stayed on station to aid the stricken Admiral Scheer. While Captain-on-the-Sea Krancke ordered all efforts be made to save the ship, including counterflooding of void spaces to stabilize the rapidly developing list, it quickly became clear that the ship had been wounded too grievously beneath the waterline, and her margin of reserve buoyancy was already gone. Within minutes of giving the order to abandon ship, her keel broke just aft of the main tower, dumping her stern back into the water to follow her bow beneath the waves. Of her complement of 52 officers and 940 enlisted, nearly half perished.

[…]

It was not all cowboy behavior from the silent service. Once the GUPPY program Balao -class submarines began entering service in force with their enhanced batteries and submarine snorkel equipment, the Naval Operations Committee contemplated dispatching submarine groups into more dangerous waters.

Operation Lloyds, a plan to render German-bound merchant traffic uninsurable from a risk perspective, began quietly in March 1941 under secret Stavka Directive No. 1107. The first phase of the plan began with the laying of mines in the Caribbean. Ostensibly an anti-submarine action, the real purpose of this public program was to pressure Venezuelan oil tankers into easily interdictable sea lanes. Once ‘accidents’ began, the submarine force began staging further ‘accidents’ through the use of Mk 18 electric torpedoes, which ran quietly and produced no discernible wake. Though slower and shorter ranged than the hydrogen peroxide fueled torpedoes, it would be difficult for civilian merchant captains to prove that their ships had been deliberately torpedoed rather than running afoul of known mine hazards.

Sporadic electric torpedo attacks soon spread beyond the Caribbean, to wherever the Stavka could plausibly claim mine risks existed. Operation Lloyds would further escalate to targeted attacks on shipping from countries that, while claiming neutrality, were giving material aid to the Axis war effort well beyond what would be considered proper. Notices were given, either directly to the embassy of the targeted states, or through intermediaries. The communiques specified that certain commodities; chiefly petroleum, ammonium nitrate, chromium, manganese, tungsten, and rubber, were to be considered war materiel and thus contraband. Coast Guard cutters as well as some naval vessels transferred to a Coast Guard flag would be inspecting and impounding ships transporting such cargos to Germany or Italy.

While this left British Commonwealth or French flagged vessels clear to continue operating, it reduced the availability of neutral flagged shipping, especially once WFRN submarines and surface ships began attacking such vessels under so-called “cruiser rules”.

Though the UASR was not a signatory to the London Naval Convention, in this testy international climate the standing orders directed submarines not taking part in secret operations to openly order unarmed vessels to stop and submit to inspection, and only attacking ships that either proved to be armed or refused to submit to inspection. Ships taken as prizes or sank required the safe conveyance of their crews. While this would normally be a huge impediment for submarines to follow, there were often enough outright communists or their sympathizers among the crews to be inspired to mutiny and to take the ship for themselves.

[…]

Operation Lloyds further inflamed tensions between DeLeon-Debs and London, but across the summer of 1941 the Tory government faced an increasingly uphill battle in the press, with the business community, and with their own backbenchers, especially the so-called “Churchill faction”. Germany had shown no respect to neutrality or the property of British nationals anywhere east of the Rhine, and news of atrocities in the war in the east could no longer be denied or downplayed.

Meanwhile, the WFRN continued to hone all levels of naval operations, both in direct combat against the Kriegsmarine and the Marina Nazionale Repubblicana(2), as well as in drills and exercises. With the scale of the naval build program underway, the Admiralty was not spoiling for a fight against the UASR, even with Japan in their corner.

The next escalation of the naval war came with Operation Willow Root, which dispatched wolf packs of submarines into the Mediterranean. After a quiet, deep transit through the Pillars of Hercules, the dispatched task force quietly maneuvered into position, hiding deep under the thermocline separating warm surface waters from cool deep waters. HY-400, a special steel alloy developed under the GUPPY program with a yield strength of 400 kpz(3), allowed Balao and later Tang -class submarines to operate safely down to 200 and 250 metres respectively, deeper than the fuze settings on most Axis depth charges.

Operating in the Mediterranean, it was now open season on Axis shipping, and following the Swedish-German occupation of Norway in October of 1941, Spanish State shipping was also subject to unrestricted engagement.

The first corsair operation, under the command of Captain Shiro Kaieda(4) aboard the submarine Balao- class submarine Cachalot (SS-337), began a reign of terror against largely undefended merchant shipping. When the Italians responded by convoying merchant shipping under escort, Kaieda implemented their prepared wolfpack doctrine, with the task force operating in three boat “coordinated attack groups”. These stable groups, already practiced in fleet problems, promoted strong coordination and esprit de corps. Like their German counterparts, attacks were coordinated through the use of encrypted wireless transmissions from Arcana KL-7 rotor cipher machines.

Once the attack groups had expended their stores of torpedoes and 13 cm deck gun shells, they would retire from the theater. Damaged boats would seek shelter in Palma de Mallorca, and if necessary accept internment in the officially neutral Spanish Free Soviet Republic. Damaged boats in Palma would be surreptitiously repaired to put to sea once neutrality would no longer be possible for the Free Soviet Republic. Some boats would be unable to complete the journey, and instead accepted internment in French North Africa.

Not all would be so lucky. Italian land-based air power was forced to rapidly develop its skills in anti-submarine warfare. Hunter-killer destroyer flotillas began actively hunting for the submarines, and not merely casually playing defense on convoy duty. And not all submariners were killed by enemy depth charges and guns.

Due to production bottlenecks on the newer Mk 16 torpedo, submarine commanders preferred to use the older Mk 14 for light ships and merchant vessels, reserving the more powerful Mk 16 for priority enemy warships. While the worst issues with the pre-revolution vintage Mk 14s had been resolved, deficiencies in the guidance gyro resulted in an unacceptably high number of them running in a circle and destroying their own submarine. One of these circular runs would result in the destruction of Nautilus (SS-306) in a January 1942 engagement off the coast of Sardinia, though thanks to Cdr Ashley’s emergency ballast blow maneuver, she had just enough reserve buoyancy for half her complement to escape a watery grave, and instead find themselves in an Italian POW camp.

[…]

In the cat-and-mouse phase of the Battle of the Atlantic, surplus submarines performed other duties. Some older boats received refits to mount an experimental bow sonar set, and were put to work hunting German U-boats. This early forerunner to the hunter-killer concept was held back by the limitations of sonar technology, but would be invaluable to the development of post-war submarine warfare.

Others were stationed as “life boat pickets” near important island airfields and patrol zones to improve rescue chances for aviators. This was especially useful for the crews of long-range patrol flying boats, which often had few recourse for safe recovery other than rescue by a lifeboat submarine.

This situation immediately changed with the Petain coup. With both the republican and monarchist right in France backing the old Marshal’s pronunciamiento, the ability of the legitimate government to retain control of the military was obliterated. Petain’s initial arrival into Paris had, aside from the fighting against the Parisian sections of the gendarmerie and a few loyalist units, initially masked itself as a parliamentary vote of no-confidence in Blum’s government.

In the weeks that followed, it became clear that this would not be a brief state of exception in the Third Republic, as the new regime assumed an openly reactionary character. During that period, the world held its breath, like a diver before the plunge into the dark, icy-cold waters. The plunge came soon, with the destruction of the Spanish Free Soviet Republic, and the taking of Gibraltar. The Pillars of Hercules were now closed, and now the Italian and French State’s ships hunted in the eastern Atlantic. One by one, all the remaining neutral states in the world were drawn into one side or the other, and the unrelenting carnage of unrestricted submarine warfare reigned on the seas.

With the passage of the Act of Union on 1 March 1942, it was open season on any ship flying the Tricolore without the Union Jack. In practice, it was not difficult to impress such vessels into Allied service.

In April, submarines of the WFRN 4th Fleet took part in the blockade of Venezuela. With no modern navy to speak of aside from a few second-hand gunboats, Venezuela had little choice but to accede to severing its relations with the Axis. The Battle of the Atlantic would now enter its attritional phase, with the German U-boat campaign intensifying, and the large Italian and French cruiser fleets now positioning to threaten Atlantic shipping. In this early period of uneasy cooperation with the Royal Navy, American submarines operated as pickets for the shipping lanes, seeking to engage their German counterparts or Axis surface warships.

Now subjected to Axis air power, operating closer to the littoral zones of Europe, losses in submarines climbed. Operating at periscope depth during daylight hours had to be strictly curtailed, and consequently identifying and tracking enemy vessels became extremely difficult. To improve task force attack coordination and provide warning against enemy airpower, some older submarines still in service were converted into radar pickets. The first two, Narwhal (SSR-166) and Argonaut(SSR-167), had just re-entered service in January 1942 as a proof of concept.

Narwhal and Argonaut had been iterations on the interwar concept of the “submarine cruiser”, large boats displacing 4,000+ tonnes submerged, armed with cruiser-calibre 15.2 cm in two single Mk 17 wet mounts. In their first life they’d been underpowered and slow, only capable of 32 klicks surface operation and 15 klicks submerged, and equally slow to dive. During their refits as test-beds for the GUPPY program, they had their internal arrangements substantially altered. The watertight seaplane hanger compartment in the aft of the conning tower was repurposed as space for air and surface search radar sets. The 15.2 cm guns and their magazines were removed, and the outer hull fixtures were streamlined. The riveted sections of the hull were reworked as flush welded surfaces.

The composite diesel direct-drive and diesel-electric system, with its multiple engine rooms and separate machinery was replaced with a diesel-electric system with more powerful prime movers rated to produce a surface output of 4,800 kW, enough for 39 klick surface running. Modifications to the ballast system helped reduce their unacceptably slow diving times.

Subsequent radar pickets would be built from late-series Gato- class orders, modified while still in construction. These modifications sacrificed some maneuverability and torpedo armament to relocate the control room from the conning tower to the main-pressure hull. The redesigned, streamlined sail would hold the radar, radio, snorkel, and periscope masts, along with a small access trunk. Additional battery banks would replace the 7.6 cm ammunition magazine and the aft torpedo room.

The radar picket submarines would serve as task force flag ships, and would almost never directly engage enemy targets. Instead, they would serve as the eyes and ears of the group, monitoring enemy communications and identifying ship and aircraft tracks with radar, coordinating attacks through the use of Arcana KL-7 cipher radios.

[…]

The most notable victories of the submarine force in the Atlantic would come in this period of total war. With attacks on enemy merchant shipping limited to the Mediterranean or the Baltic, the submarines that were not diverted to prosecute the UASR’s war of choice against Imperial Japan would now spend their time hunting enemy surface ships in support of the surface fleet.(5) Killing the wounded stragglers of surface action became the highest priority, especially after the loss of Haiti (BB-59) to U-501 after the Battle of the Westfjords.

In the days that followed, Blackfin (SS-322) identified the track of the wounded German battleship Großedeutschland limping back to Norway with destroyer cover. After penetrating the screen, Blackfin achieved a shooting solution, hitting with a single Mk 16 out of a spread of four. Engaged by enemy depth charges, Blackfin would ultimately be lost with all hands, but her single hit would prove enough to finish off Großedeutschland. A final perfunctory scuttle order was given for the sake of wounded pride, and the loss of the ship was immediately made a state secret.

Similar elan would finish off the German battlecruiser Goeben(6), limping home after sinking the battleship HMS Royal Oak and heavy cruiser HMS Norfolk during an arctic convoy attack. This would be the first action by a Tang- class submarine: Bass(SS-566), namesake of a boat lost in a war patrol during the Civil War.

Like their counterparts in the German Elektroboote program the Type XXI, the Tang- class were true submarines optimized for submerged operation, and assembled from prefabricated sections like the Liberty and Victory merchant ships. Their hulls were streamlined and shaped for underwater performance instead of surface seakeeping. The wide conning tower platform with its cramped control room was replaced by a streamlined sail like the radar picket conversions. The larger control room in the main pressure hull allowed more effective direction of sensors, maneuvering, and weapons in battle. With a shorter, wider hull than her predecessors, the Tang -class could submerge more quickly and maneuver more agilely under water.

Four 126-cell lead acid batteries provided greater submerged power and faster charging times at the expense of an eighteen month service life. This allowed them to operate submerged for several days while still being able to cruise at 10 klicks, and then to recharge at snorkel depth in about four hours. When engaging enemies, they could sprint submerged at up to 34 klicks, or conversely sprint away at her 250 metre test depth. With her distinctive shark-fin sonar domes at the bow, sail, and stern, they had greater passive and active detection ranges, and could be used in conjunction with the WFRN’s first submarine launched acoustic homing torpedo, the Mk 22.

The Tang- class carried no deck gun. While this limited effective patrol time, the other advantages more than outweighed this in practice. Despite seeing the heaviest action against the IJN in the Pacific theatre, the Tang- class suffered the lowest loss rate of the main submarine classes in the war. And while their per capita merchant shipping tonnage lagged behind their predecessors, they sank more enemy surface warships and submarines than any other class.

When engaging Goeben in the North Sea, Bass made a deep sprint through her destroyer screen, which could not maintain a reliable sonar track on her while they tried to match her 34 klick speed, both active and passive sets overwhelmed by the noise of their own machinery. This allowed Bass to confound the limping Goeben ‘s attempts to zig-zag, and achieve a broadside shooting solution, executed at 900 metres. Of the the salvo of four Mk 16s, two would hit and render the battlecruiser dead in the water. Fires started by the torpedoes would eventually cook off one of her 10.5 cm battery’s magazines, further frustrating damage control.

With Bass still lurking, and fruitless salvoes of depth charges yielding no signs of submarine wreckage, and the ever present threat of air attack in the front of his mind, KzS Robert Weber calculated that power could not be restored, nor could be assured that flooding could be stopped. Consequently, he ordered the ship abandoned, with a coup de grace delivered by the destroyer Z58.

Ironically, a second attack would not have come from Bass. Cdr Howard Gilmore had been creeping away to avoid the circling destroyers. Bass ‘s batteries had already been partially discharged before the battle, and the high speed attack run and initial escape had put the battery condition dangerously low. She wouldn’t have the power for another run, and would have to shut down all non-essential systems to ensure she had adequate margin to find her way to periscope depth after nightfall.

But her sonar operators heard the tell-tale whine of a four-shot salvo of G7a wet heater torpedoes, and the thump of their distant warheads, and marked a probable kill of a Goeben -class battlecruiser in the ships log.

[…]

As the UASR and the nascent Franco-British Union shifted awkwardly from cobelligerents towards allies in a common struggle against fascism, the silent service had to swallow some bitter pills. The intensification of the U-boat war, made possible by full access to the French and Spanish coasts, imperiled the industrial economy in Great Britain. Overseas imports were the life blood of the island’s economy. 56% of the country’s food calories were imported, as were most industrial inputs.

While the Royal Navy had made major advancements on its own in antisubmarine warfare, it was inevitable that a lack of urgency from peacetime and the lack of direct application left them behind the curve. They would have to catch up. And quickly; Germany had a full two years to refine its tools and doctrine, and they were rapidly schooling their French and Italian allies on the subject.

American destroyermen and submariners would have to do their part to strengthen the Royal Navy’s hand. For the officers of the silent service, on average younger and more ideologically committed to communism than Navy old guard, this was a bitter pill to swallow. However necessary the struggle in the present, it meant arming the Red Navy’s greatest potential adversaries with the tools to frustrate a decade of study and preparation.

The “Loomis Mission” to London would furnish design and technical literature on a number of classified systems, including the AN/BQG-42 Passive Underwater Fire-control System from the Tang- class, the Mk 26 active homing torpedo, the Bell Labs seawater battery, the GUPPY hydrodynamic studies, as well as much of the ongoing cryptanalysis of the German Enigma and Lorenz ciphers. Similarly, the Royal Navy was furnished with completed ships, principally destroyer escorts (DE) and escort carriers (CVE) on a Lend-Lease basis.

While the WFRN would receive 99 year leases on a network of naval bases around Africa and the Indian Ocean, and the war economy would be furnished with in-kind transfers of raw materials, these open-ended agreements signalled a new counterrevolutionary understanding between the two states. It would preserve the peace after the present enemy was defeated. And in this dangerous present, where without the benefit of hindsight could not be assured that Britain would remain steadfast in the anti-Nazi cause, giving the Royal Navy the means to recover from excessive early losses in screening ships would keep them in the fight. Deliveries of surplus escort craft, which the WFRN would struggle to man due to the ever present manpower crisis, would also allow the Royal Navy to avoid costly disruptions of its own naval production, and quickly put naval reservists on the sea, learning and doing rather than waiting on the shore.

[…]

The truest test of the WFRN submarine force would come in the Pacific against the Imperial Japanese Navy. The IJN was a true peer adversary, and had been studying how to fight for control of the Pacific since the guns fell silent in the Great War. Technologically, they had proven to be true peers, and had not needed to climb out a massive ship deficit of losses and defections in a Civil War. They also knew, intimately, the details of every pre-revolution American ship class, as the White Exile regime in Havana downsized a fleet it could not afford to keep, selling specimens either directly to Japan or to their allies in the UK.

Much of the Pacific had fallen into Japan’s hands like ripe fruit, a product of triangulation by the old colonial powers against the UASR. These condominiums over the Philippines and the Dutch East Indies furnished the Japanese industrial economy with crucial raw materials, especially oil and rubber. The Concordist regime cultivated its satellites carefully, and would at least initially not need to rule at the point of a bayonet.

While the industrial economy at home overheated from the rearmament prerogatives of the regime, overclocked as it was at the present it had furnished the country with a fleet that was at a dead-heat in battleship and carrier tonnage to the WFRN in 1942. They had comparable technology at the cutting edge, and had managed to beat the UASR in putting centimetric radar in production. Their destroyers and cruisers were armed with the potent 61 cm Type 93 torpedo “Long Lance”, which improved range and speed by utilizing pure oxygen instead of compressed air for the bulk of the engine run time.

Japanese submariners were brave and resourceful as well, and their boats were numerous and at least as good as the German pre-war types. While this was the one area where the WFRN had a major technological advantage over the IJN, it was not technology that held them back, but rather doctrine.

The WFRN Silent Service had been schooled to attack the logistical backbone of the modern industrial economy, and engage enemy warships as a secondary priority. With the IJN, the attrition of enemy warships was the primary aim of all branches of the Navy, bleeding the enemy in preparation for a decisive series of engagements that would yield fleet supremacy over the Pacific.

Japan’s industrial economy was dispersed across Manchuria, Korea, and the Home Islands, and dependent on a wide range of imports from further afield. The sequence of events following the French quasi-civil war had put Japan onto a collision course with the British Commonwealth, a war that neither state initially desired, but which cut off the country immediately from most ore, scrap metal, cotton, and advanced machinery, and imperiled the status of the condominiums. Ambitious filibusters launched by IJA officers poured fuel on the fire, and the occupation of French Indochina against the “rebels” there loyal to the Third Republic pushed matters beyond repair.

As the undeclared border war in the Soviet Far East festered, the die was cast. After years of undeclared limited war fought between proxies and expeditionary groups, the Central Executive Council of the UASR voted unanimously in secret session on 14 August 1942 to declare war on the Empire of Japan, though in truth the matter had been decided some weeks before. The Clausewitzian war of observation, limited in geographic scope, aims and methods, would now veer towards the Absolute.

Within minutes of the transmission of the declaration, the unrestricted submarine warfare campaign would begin, launched by boats prepositioned along trade lanes in the previous weeks.

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1. IOTL, the US Navy designed and produced six iterative classes in small numbers over the course of the 1930s before the Two Ocean Navy bill resulted in mass production. To not get too lost in the weeds, I’ve treated those classes as a series of emergency Civil War builds and refits, with TTL’s Gato being the first design that could incorporate all the operational experience from the Civil War.
2. This is a slight anachronism by the author. Mussolini had not yet deposed Victor Emmanuel III, but since the country spent most of the war styled as the Italian National Republic, it and its institutions are more commonly remembered in their fascist-republican form instead of the pre-war compromise under the constitutional monarchy still operating under the 1848 Statuto Albertino.
3. Kilopièze. Pièze is the unit of pressure under the metre-tonne-second metric system, adopted by the US government for wartime industry during the Great War, and also standard in France and the Soviet Union. Though it will eventually be superseded by the metre-kilogram-second based SI like OTL, such units are still used by convention and easily convert to SI units. 1 pièze is defined as 1 sthène (tonne-force) per square metre, and is thus equal to 1 kilopascal.
4. Formerly a Kaigun-tai-i (Lieutenant/OF-2) in the Imperial Japanese Navy, and the navigational officer of the submarine I-53. Already a radicalized communist sympathizer, he led a mutiny on I-53 during the American Civil War when his commanding officer ordered the sinking of the battleships at Pearl Harbor during the chaos of the ongoing Pacific Fleet mutiny, and subsequently defected.
5. This is a bit of a retcon of the events as initially presented. There will be a later update fleshing out the sequence of events for the Pacific War more fully.
6. Essentially, the OTL O-class design study, a 29,000 tonne ship capable of 35 knots, and armed with six 38 cm guns in three twin turrets.

*[WPA]: Works Progress Administration *[NBI]: National Bureau of Investigation