Shipbucket

FLUFF: PLAN DOG; RAINBOW 2 AND HECTOR BYWATER

First, before we present the consequences of this AU as speculated, let us see where the United States, Japan and Great Britain are. Immediately, the consequences of the Treaty of Paris (1899) should be factored into the setup. In the RTL, the US and Germany split up Spain’s Pacific possessions between them. Germany is particularly keen to land territory in New Guinea, the Bismarks and the islands north of the Solomons Islands chain. The US, with a full-blown insurrection on her hands in the Philippines and having tasted war at the hands of the Spaniards, wants nothing to do with a clash with Germany over territories she regards as expensive to administer and probably not worth the return on investment as the Philippines is turning out to be.

In the AU, John Hay tells Bernhard Graf von Bülow to go to hell as for the United States he buys up the Marianas, Marshalls, Carolines, and the Gilberts along with the northern Philippines from Spain (2 million dollar bribe to Ventura García-Sancho, Marquis of Aguilar de Campoo under the table is part of the official purchase and not counted in the public payout.), in a package deal. This whole 100 million US dollar expense on an almost already bankrupt federal government is the gift that keeps on giving grief.

Roosevelt’s admirals; Watson, Schley, Mahan, Fahrquaur, Dewey and Sigsbee; the day after the deranged lunatic, Leon Czolgosz, makes him president by shooting McKinley, demand a new canal so they can cut transit times between the Atlantic and Pacific fleets. There is one French project, The Panama Canal Company, that is currently bankrupt and that McKinley’s maniacal Secretary of the Army is secretly taking over in a Panama filibuster. Elihu Root is not exactly playing with a full deck in the deal. The admirals do not like the dangers of a war with Columbia that could bring i9n Great Britain and they are not enthused about the French route anyway. They want the Nicaragua canal. It will be wider, easier to dredge, not as many locks and it promises Lake Nicaragua as a convenient anchorage to park ships in a trans-isthmus movement. Besides, conquering Nicaragua is easier and cheaper than bribing Columbia, or so they think.

Roosevelt, never one to settle for a hamhock, when he can have the whole hog, goes for both ditches on the sound principle, that double the canals means that one of them can be exclusively USN used in wartime without interrupting neutral shipping (and the transit fees the US intends to collect for the benefit of Panama and Nicaragua of course.)

Teddy Roosevelt does a lot of questionable imperialist things in the McKinley AU after McKinley is assassinated. He is almost positively British in the way he behaves. He secures a Shanghai concession from China which is something that not even Japan attempts, takes over half the Sulu Sultanate in a pure conquest war, prosecutes a war of extirpation in the northern Philippines, takes over administering Chile’s copper mines, makes Cuba a defacto colony, ditto for Ecuador, reduces Hawaii to a USN administrative enclave and that is what he does for real.. All I do for the Hoover AU is presume that Hay gets McKinley to agree to all the side deals, Hay has going in Paris after the Spanish American War.

Roosevelt afterwards in the AU allows Hay a free hand to thwart the Germans at every turn, In the RTL, Kaiser Wilhelm II tries to inveigle Roosevelt into an anti-Japanese alliance. Roosevelt at the time tells him to go to hell, especially after the Venezuela debt crisis, when Roosevelt reduces that country to a defacto American satrapy to keep the European creditors out and force American creditors to the head of the line. In the AU, this does not have to be tweaked at all. In fact, WW I rather much runs on schedule, with the only AU tweaks being that the American army uses their own native built artillery, airplanes, straight pull Mannlicher rifles and the Hotchkiss air cooled gas operated machine gun, which they sell to the French, instead of the other way around.

WW I Germany has a lot of reasons to hate the United States. The hate is mutually shared.

Wilson still bungles Versailles and Harding still inherits a huge belated bloated Congress passed WW I naval building program after Wilson holidayed the USN’s construction schedules from 1913-1916. Charles Evan Hughes does what he does at the Washington Naval Conference, Sims sneaks in his carriers and the “substitute stretched Marylands” to replace the Lexingtons, and by 1928 when Hoover rolls into office, Great Britain, Japan and France know they have been had; especially in the Pacific.

Great Britain’s crown government (Baldwin/George V) is financially and politically in no position to do anything about it. Neither is Leon Blum of France. However… Tanaka Giichi, Prime Minister of Japan is in a position to do great harm. In the RTL, this conservative actually did his ineffectual best to tamp down the crazies who pulled off a retaliation of the Jinan Incident, where Japanese nationals were Chinese butchered in response to a Japanese massacre of a Chinese truce delegation and the subsequent assassination of the Chinese warlord, Zhang Zuolin, who ordered the murders. He was blown up. That would be the first big OOPS. The Mukden Incident follows hard upon that disaster, but in this case, junior Japanese officers in a political practice known as Gekokujō (leadership from the bottom) in this AU, blow up a train full of their own generals, blame it on the KMT tenuously under Chiang Kai Chek and the Second Sino-Japanese War is on.

The US consul in Nanking charters a President-class liner that has docked at Shanghai on one of its regular San Francisco to Shanghai runs. Americans who wish to evacuate from Shandong, Anhui and Jiangsu provinces to escape the onrushing Chinese and Japanese armies are packed aboard and sent out under a big fat red-cross flag. Not even an American flag is considered a safe banner under the circumstances. There are 2000 missionaries aboard. The ship is bombed and strafed northeast of Taipei, Formosa; just as the liner is about to turn south for its run to the nearest American stronghold, Manila.

The Japanese claim they do not bomb it, and even if they did, it is an accident, and it looks like a Chinese troop transport and why is it not flying the American flag?

Does not matter in the AU. 2000 drowned “missionaries”, the sudden fortuitous publication in the San Francisco, California Chronicle newspaper of The Tanaka Memorial and Hoover has a war on his hands in this AU.

Never mind that accidents, incidents, American journalists and Chinese Nationalist lies and Russian communist propaganda conflue. We’ll see how it turns out in a nonce.

Yup. They do use poison gas on each other. Hence the massacres.

Map by Tobius.

Hi Tobius:
Another question. I note that you favored the flush deck design over the stepped one. But, specially in the drawings of less displacement vessels, the height over the water line of the hull in the stern looks too high (almost a deck high). May I ask why are you doing that? Cheers.

edited.

The ship volume rule, tuna keel and the Atlanta class example again.

FLUFF: PLAN DOG; RAINBOW 2 AND HECTOR BYWATER (PART II)

How do they stack up against each other? If this was Republic of Koko 1931, I’m not confident Mister Hoover’s Navy would have a snowball’s chance in a blast furnace. I see a lot of subtle things BB1987 introduces that geographically and technologically makes the RTL USN position difficult in his AU for WW II, much more so for a WNT RTL USN.

However, this is my AU and the difficult opponent is the Japanese IJN of 1931, which is still more than a handful for the 1931 AU American navy. With the shifts in naval parameters, one would think in a battleship dominated era, that the IJN just post WNT in this AU is in a happier position than its RTL counterpart. It has near naval parity (actual superiority in the Pacific), with the Americans, a somewhat faster line (28 knots versus 25 knots), a British alliance of sorts and a somewhat stronger political and military position in northern China in the AU thanks to the much more over-eager Kwangtung army. The AU drawback is that the Americans have those central Pacific islands and their lifeline to the Philippines is much stronger. Truk and Eniwetok are US anchorages, not Japanese. The Americans also hold Rabaul, so that any Japanese adventure into the western Dutch East Indies to steal the oil fields will have the Americans plonked on Japan’s flank immediately. The Japanese will have to be far more cautious and a bit more devious in their war-making. Their opening moves being Chinese restricted are a series of coastal landings to secure Chinese ports through which some European power or other western power (read America) might send the KMT military aid and supplies. That would make some political sense, since the Japanese lack the means to blockade 2000 miles of Chinese coastline without inciting a naval war. Even the Imperial Japanese Army knows that much.

So what goes wrong? Well… there is the SS Milliard Fillmore Incident. And the yellow press in America does not help with publishing “The Tanaka Memorial” lie. And then the Japanese use poison gas and experimental plagues in Zhejiang province south of the Shanghai enclave in conjunction with the “Rape of Nanking” to block the KMT “Great Northern Expedition’s southern prong, since if the KMT army reaches the coast it will cut off all those southern coastal landings the Japanese execute. This would be a disastrous loss of face. However, a perfectly reasonable move by the Japanese military leadership on the local scene, being swamped by hordes of Chinese KMT fanatics as they see it, kind of makes the situation between Japan and America that Katsuji Debuchi, the hapless Japanese ambassador to the US, tries to ameliorate; go from extremely difficult to the “he has to take the first train to Canada” to avoid arrest and imprisonment as an enemy alien.

Baldwin, under the circumstances, may observe the diplomatic niceties and declare Britain’s firm neutrality concerning the mess and Leon Blum may ditto it for France, but Hoover is like unto Tanaka as regards the onrush of events. The USN already has its orders from Secretary Charles F. Adams to whittle down the Japanese Navy should Congress declare war. PLAN DOG is such a series of staged surprise attacks on Sasebo Kogashima, Yokusuka, Hakodate and Kantan and Uchirowan Bay. Those ports and bays are to be mined and blockaded by submarines. The US Pacific fleet logically operates as a covering force, but from where and to do what? This is why TRUK becomes important. In the RTL, the Japanese hold onto it until WW II’s end as they do for Rabaul. In this AU, however, the US holds it. From Truk (Chuuk) and Eniwetok, the US Pacific fleet can mount a distant blockade and stage a series of raids on the Japanese coasts as the British did in WW I to Germany. The first of these raids, will be a doozy. (See below.)

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NAVY TECHNOLOGY 1931:

When it comes to reconnaissance, the Japanese and the Americans in 1931 have already rejected the airship as a viable platform. Though, ten years later the USN will operate a blimp fleet in home waters that will effectively neutralize enemy submarines, this is 1931 and the reconnaissance for the fleet work needed operates in a Pacific region called Typhoon Alley. That would be the waters east of the island chains and landmasses that stretch off east Asia’s shores out from the Philippines to Japan and clear into the nursery area of storms, the north Pacific. Now the Japanese are great weather forecasters, but even they pale in comparison to the US Weather Service. From the Aleutians and from weather ships stationed in the US Mandates, the Americans notice a freight train of storms that follow, one after another from August into September, all on the same track. The Second Sino-Japanese War is scarce 2 months old when the Japanese expeditions on the south Chinese coast, and the Japanese and Chinese KMT armies fighting for Jiangsu Province are hit with the first of 9 storms, one right after the other. These are not small storms. The IJN is forced to port up, not only along the Chinese coastal ports, but also in their home Japanese ports. This is unfortunate for them.

American submarines, in this AU, come in two flavors: those which lay mines across the mouths of enemy harbors and those which lie outside enemy harbors in wait to ambush enemy traffic, to and fro. There are 5 of them deployed at Subic Bay, and 12 at Pearl Harbor, but the main submarine base just happens to be at Guam. And there are 24 boats bobbing happily there at Apra Harbor at the moment. The Japanese do not know this, because while they do have some flying boat aircraft that can reach Guam , their H1Hs are being chased off by Boeing F4Bs and Grumman FFs based out of Agana. How do the Americans detect the Japanese snoopers without radar? Well like the Japanese with their “Yokohama Trumpets” the US uses British invented acoustic collectors called REDCAR and a trumpet horn system, also British invented, called BIGEAR. Good enough to give about 12-15 minutes of warning in 1931, which at the era’s aircraft cruise speeds of 50 m/s, translates into 36,000 meters detection threshold range. OOPS. Better amend that to the H1Hs are splashed before they can get a radio message off. 8/.

Anyway, in 1931, do not expect 虹岳島空襲。軍の練習ではないです。It will be, 虹岳島湾港に敵の潜水艦。攻撃を受けております。The air raids will follow after Admiral Eisuke Yamamoto receives word at Yokosuka that Hei and Ise are kissing mud at Sasebo, Mutsu has blown up and capsized at Kogashima and that Akagi and Amagi are sunk in deep water at Uchirowan Bay. Kaga is limping into Yokusuka with a couple of torpedo hits which will drydock her for months. This costs the Americans 6 submarines out of the 30 involved, but in the calculus of naval war, Japan goes from naval parity in the Pacific to a mere coast guard, as the German High Seas Fleet did in just 2 days of fighting in WW I and that is a cheap price for the USN to pay to do it. The American ambassador hand delivers the demarche note to Tanaka just as the USS Charpwick puts a couple of fish into the Mutsu. No torpedo nets? No picket boats? That is what my research indicates is the Japanese condition at their naval facilities in 1931. At least in the RTL when the Japanese attacked Pearl Harbor, the USN had pin-balled the harbor with hydrophones and mounted a picket patrol destroyer guard. It is just barely possible that one of the five Japanese midget subs got past the USS Ward, but not very likely. Three of the wrecks are known. Nothing has been found inside the harbor, despite the recent claim by revisionist historians that a midget sub might have gotten USS Oklahoma. Anyway, Japanese bays are deep, entrances are wide, currents are strong and a GUPPY would love those conditions to snort around in.

Next up, How do things go at Lingayen Gulf?

I'm thinking of adding a 500 ton torpedo boat to the lineup. Considering the Japanese problems with the Chidoris, that should prove interesting.

The Japanese will run into that around the Philippines

edited.

If one goes to a Pacific hydrography chart., one sees the reason Japan is a Japanese merchant ship happy hunting ground for US subs.

Deep basins surround the Japanese home islands but there are sound baffling trenches that lead from those basis into the various straits and into their major naval base harbors. A sub can operate in those noise shadows or in the shrimp beds in the offshore coastal shelf shallows. Other shallow trench basins provide a highway for a sub to sneak into Japanese fleet exercise areas and anchorages. Many Japanese harbor channels are multiple ingress and exit, with surface to floor depths too deep to net and with currents to mine with moored mines. And in 1931 there are no CAPTOR mines. Bottom mines are too deep.

FLUFF: HECTOR BYWATER PART III: HOW DOES THE AU USN STACK UP VERSUS RTL?

This is a bit of fluff to explore the way technically things look before we get back to the Pacific War. As is the case in technical analysis, one likes to have a benchmark, or set of benchmarks.

In this case, the IJN and the IJA provides good ones.

Aircraft carrier: being typical is the KIJMS Akag
Class and type: Akagi class (In this AU, the Amagi, survives the earthquake and is also constructed to the same profile.)
Type: Aircraft carrier
Displacement: 36,500 long tons (37,100 t) (standard); 41,300 long tons (42,000 t) (deep load)
Length: 260.67 m (855 ft 3 in)
Beam: 31.32 m (102 ft 9 in)
Draught: 8.71 m (28 ft 7 in)
Installed power: 133,000 shp (99,000 kW); 19 Kampon water-tube boilers
Propulsion: 4 shafts; 4 Kampon geared steam turbines
Speed: 31.5 knots (58.3 km/h; 36.2 mph)
Range: 10,000 nmi (19,000 km; 12,000 mi) at 16 knots (30 km/h; 18 mph)
Complement: 1,630
Armament: 6 × single 20 cm (7.9 in) guns, 6 × twin AA 12 cm (4.7 in) AA guns
4 × 8 barrel 4 cm (1.6 inch )”Yokusuka Organ” 2 pounder AAA guns
Armor: Belt: 152 mm (6.0 in)
Deck: 79 mm (3.1 in)
Aircraft carried:
66 (+25 disassembled as reserve in the hanger).
Note:
1 In the AU, the Japanese do not have access to the their version of the gas operated Hotchkiss or the French director that comes with it., so they are left with the Vickers 2 pounder Pom Pom as their AAA medium range weapon. This gun in the multiple barrel mounts comes with the Japanese version of the repeater pointer Mark III directors the British use. This limits the Yokusuka Organs to L/A barrage fire.
2. The air group in 1931 is as follows. 22 fighters, 32 torpedo/level bombers and 12 scouts, artillery spotter aircraft.
Types available from Japanese production
Nakajima A1N (Fighter, Gloster Gandet)
Nakajima A2N (Fighter, Boeing P-100)
Mitsubishi B2M (Torpedo/level bomber, indigenous design.)
Mitsubishi 1MR (Scout plane of indigenous design).
It should be noted that except for the Boeing P-69 and P-100, bought from a third party (Argentina) and Nakajima reverse engineered with a British engine (the P-100 is the F4B in USN service), many of these aircraft are derived from the work of British expatriate; Herbert Smith; who comes from the Sopwith Aircraft Company of Sopwith Camel fame. Mitsubishi, when they need an aircraft expert to compete with Nakajima , hire HIM. If the US had known what he is doing from 1920-1924 with Mitsubishi and what Smith’s Japanese students will do with what he teaches them, the Americans would have killed him before he ever set sail for Japan.

The AU Lexingtons which are typical:
General characteristics (as built)
Type: Aircraft carrier
Displacement: 36,000 long tons (37,000 t) (standard); 43,055 long tons (43,746 t) (deep load)
Length: 885 10 inches ft (270. m)
Beam: 108 ft 4 inches (33 m)
Draft: 30 ft 5 in (9.3 m) (deep load)
Installed power: 180,000 shp (130,000 kW), 12 diesel electric complexes, 15,000 hp (10,833 kW) each
Propulsion: 4 shafts, 4 sets of electric transmission final drives
Speed: 33.25 knots (61.58 km/h; 38.26 mph)
Range: 10,000 nmi (19,000 km; 12,000 mi) at 10 knots (19 km/h; 12 mph)
Complement:
2,000 (including aviation personnel) in 1931
Armament: 4 × 2 twin 3.9-inch (10 cm) DP guns AAA/ASh
16 × 4 barrel (3 cm) anti-aircraft guns
Armor: Belt: 5–7 in (127–178 mm)
Deck: 2 in (5 cm)
Gun turrets: 0.75 in (2 cm)
Bulkheads: 5–7 in (12.5–18 cm)
Aircraft carried: 64-78 in air-group with 32 spares in hanger^1 and ^2
Aviation facilities: 2 catapults, (drum cable accelerators, limited to 4,000 kgs at 45 m/s)^3

^1 Going into the Great Pacific War, the USN opens up with this lineup.
Boeing F2B biplane fighter
Boeing F3B biplane fighter
Boeing F4B biplane fighter, best of the American fighters available.
Curtiss F6C obsolescent biplane fighter
Curtiss F7C obsolescent biplane scout/fighter
Curtiss F8C current biplane scout/fighter
Martin BM scout/dive bomber
Consolidated BY-1 level bomber
Great Lakes GF, reconnaissance/utility seaplane
Vought O2U scout/fighter, famous for “killing” King Kong.

^2 The Japanese will find that they are handicapped by the Armstrong Siddley Jaguar engine. In a rare mistake for the Japanese, this piece of absolutely dreadful engineering is licensed and built by Mitsubishi to power some of their aircraft. On the American side of the ledger, the Boeing F4B in their fighter line historically and in this AU is outclassed by the Nakajima A1N in both climb and turn. As goes the Boeing F4B, so goes the lineup type for type. As in the RTL 1941 Japanese torpedo planes are better than American ones, while dive bombers are the American advantage in this AU. Oddly enough; the Americans have an edge in shipborn reconnaissance in aircraft as well as doctrine.

Comparing the aircraft carriers to each other, in the AU, the Japanese are slower, have better turning circles, better flight deck armor, worse torpedo protection, and smaller hangers, more fly-off decks and generally better attack and fighter aircraft. In 1931 however, the Americans have working bow catapults (2 of them on Lexington to Akagi’s 0. ) which allow for a strike package of 40 + aircraft off in 30 minutes. The Americans also have better scout planes and more of them. Neither navy has entirely abandoned the British battle model of tacking the aircraft carrier to the battle line as a tail-end Charlie, though both navies have concluded that the aircraft carrier needs to detach and flee to the rear while the battleships slug it out. As a general evaluation in 1931, either RTL or AU, these carriers are too close to each other to say, it will be up to technology. The better ships purely depend on the better trained crews. Edge in the beginning goes to Japan in that regard. More time at sea + more intensive and brutal mission oriented peace-time training makes the “war” trained surface ship Japanese sailor about 20% more efficient than his peacetime American counterpart. Now after the shooting starts and the Japanese navy loses many signalmen strikers, mechanics, engine room gangs, and carpenters of all types and their petty officer corps is wiped out, they are done. 120 day replacement wonders will lead to AU disasters typical of the RTL HIJMS Shinano. The IJN will never recover what damage control discipline they have once their specialists are gone. In that one critical area which is training, the USN with its huge training establishments and Atlantic fleet cadre reserves will enjoy superiority.

IN THE AIR:

Objective research shows that in the RTL 1930s, the Russians and the Chinese engage the IJA and IJN in the air and usually come out the loser in the exchange. The Russians never seem to learn, but the ROCAF pilots stuck in those Polikarpov and Ilyushin deathtraps that Stalin’s Russia supplies, became very good at the dogfight game until killed off by flying too many missions. Long before Boyd teaches the USAF about energy management, the ROCAF pilots know about ZOOM and BOOM as applied against nimble Japanese aircraft that can out-360 circle them in a turning fight. This is exactly what USN pilots are not taught, though the Boeings and the Curtisses are inadvertently set up for this kind of aerial combat approach. What the USN does have on the Japanese is WW I combat experience, it never gives up. In 1931 or 1941, the Americans fly like the French or Germans do, not the British who have dreamed up new and terribly wrong fighter formation tactics that will cost them dearly until they get back to their own Royal Flying Corps roots. The Japanese have learned the wrong British methods of 1931 and they will use them against the USN. The Americans will simply cut them to ribbons, even though the Japanese aircraft line is nimbler, faster and at this date, has more reliable aircraft. The Three Vick is a disaster.

But enough about aircraft carriers; this 1931 AU or RTL era is still arguably dominated by the battleship and surface warfare.*1 When it comes to battleships the USN will show the IJN what is what. Right?

Let us look at the 1931 Japanese standard: HIJMS Hyuga:

General characteristics of Ise class battleship
Class and type:Ise-class battleship
Displacement:38,872 long tons (39,496 t)
Length: 219.62 m (720 ft 6 in)
Beam: 33.8 m (110 ft 11 in)
Draft: 9.14 m (30 ft 0 in)
Installed power: 33,556.5 kW (45,000 shp)
Propulsion: 4 × Parsons turbines, 24 × Kansei boilers (as built), 24 × Kampon boilers (after 1935 refit),
4 × shafts
Speed: As built: 23 kn (43 km/h; 26 mph); 25 kn (46 km/h; 29 mph) when re-engined
Capacity:
As built: Coal: 1,000 tons (normal), 4,000 tons (maximum);Fuel Oil: 4,500 tons of fuel oil when re-engined
Complement: 1,463
Armament:
As built: 12 × 356 mm (14 in)/45 cal guns (twin turrets, 2 fore, 2 mid, 2 aft), 20 × 140 mm (5.5 in)/50 cal guns, 16 × 12-pounder (76 mm (3 in)) guns, 4 × 12-pounder (76 mm (3 in)) AA guns, 6 × submerged 533 mm (21 in) torpedo tubes
After refit: 12 × 356 mm (14 in)/45 cal guns; 16 × 140 mm (5.5 in)/50 cal guns; 8 × 127 mm (5.0 in)/50 cal DP guns; 4 × 8 barrel Type 96 4 cm (1.6 in Pom Pom) AAA guns
4 × 533 mm (21 in) torpedo tubes
Armor:
Belt: 228.6 to 305 mm (9 to 12 in) (amidships); 76 to 127 mm (3 to 5 in) (ends)
Deck: 31.75 to 63.5 mm (1.25 to 2.50 in)
Turrets: 203 to 305 mm (8 to 12 in)
Conning Tower: 152 to 305 mm (6 to 12 in)
Aircraft carried: 3 × floatplanes
Aviation facilities: 1 × catapult, compressed air type.

It should be of note that the Japanese 14 inch (35 cm)/45 caliber gun is a British design.
Specifications: Vickers: 14 inch/L45 BLNR (Wellin interrupted screw block)
Weight: 86,000 kilograms (86 t)
Barrel length: Bore 52 ft 6 in (16.002 m) (45 calibres)
Shell:673.5 kg (1,485 lb)[1]
Calibre: 14-inch (355.6 mm)
Elevation: -3° to +43°
Rate of fire: 2 rpm (optimistic. It was more like 45 seconds.)
Muzzle velocity: 775 m/s (2,540 ft/s)
Effective firing range: 28.7 degrees; 32,810 yards (30,000 m)
Maximum firing range: 38,770 yd (35,450 m)

The Japanese gun in 16.1 inch/L45

Specifications
Weight
102,000 kilograms (224,872 lb)
Length: 18.84 meters (61 ft 10 in)
Barrel length: 18.294 meters (60 ft 0.2 in) (bore length)
Shell: Separate-loading, bagged charge
Shell weight:1,020 kilograms (2,250 lb)
Caliber:41 centimeters (16.1 in)
Breech: Welin breech block
Elevation: –2° to +35° (later after 1935 –3° to +43°)
Rate of fire: 24 seconds (More like 45 seconds)
Muzzle velocity: 780–790 meters per second (2,600–2,600 ft/s)
Effective firing range: 30,200 meters (33,000 yd)
Maximum firing range: 38,400 meters (42,000 yd)

To contrast with the Ise, let us look at an AU “Stamdard battleship”

General characteristics
Class and type: Maryland-class battleship
Displacement: 32,600 long tons (33,100 t)
Length: 656 ft 2 in (200 m)
Beam: 97.3 ft (29.7 m) (original), 114 ft (35 m) (rebuilt with torpedo defense added.)
Draft: 30 ft 6 in (9.30 m)
Installed power: 90,000 shp (65,000 kW), 6 diesel electric complexes, 15,000 hp (10,833 kW) each
Propulsion: 4 shafts, 4 sets of electric transmission final drives
Speed: 25 knots (46.3 km/h; 28.77 mph)
Range: 10,000 nmi (19,000 km; 12,000 mi) at 10 knots (19 km/h; 12 mph)
Complement: 1,080 officers and enlisted
Armament: 8 × 15.75 in (40 cm)/L45 guns (4 x 2)^1
12 × 7.9 in (20 cm)/L45 guns (6 x2)
16 × 3.9 in (10 cm)/L50 guns DP AAA/ASh
4 x 4 barrel Remington 3 cm/L50 AAA guns.
Armor:
Belt: 8–13.5 in (20–34 cm)
Barbettes: 13 in (33 cm)
Turret face: 18 in (46 cm)
Turret sides: 9–10 in (23–25 cm)
Turret top: 5 in (13 cm)
Turret rear 9 in (23 cm)
Conning tower: 11.5 in (29 cm)
Decks: 3.5 in (8.9 cm)
Aircraft carried: 1 × floatplanes (peacetime); 4 x floatplanes (wartime)
Aviation facilities: 1 × aircraft catapults (after refit; 2 x catapults)

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The notional US 15.75 inch/L45 gun…

Specifications
Weight: 230,948 lb (104,756 kg) (without breech), 235,796 lb (106,955 kg) (with breech)
Length
736 in (18.7 m)
Barrel length: 720 in (18 m) bore (35 calibers)
Shell AP Mark 3: 2,222 lb (1000 kg) armor-piercing (AP) (Mark 1 gun)
AP Mark 5: 2,240 lb (1,020 kg) AP (Mark 5 and 8 guns)
HC Marks 13 and 14: 1,900 lb (860 kg) High explosive (HC) (Mark 5 and 8 guns)
Caliber: 15.76 inches inches (~ 40 cm)
Elevation: -4° to +45°
Traverse: 300° max/280° min
Rate of fire: 1.5-2 rounds per minute
Muzzle velocity:
AP Mark 3: 2,700 ft/s (790 m/s)
AP Mark 5: 2,520 ft/s (770 m/s) Full Charge
HC Marks 13 and 14: 2,635 ft/s (803 m/s) Full Charge
AP Mark 5: 1,935 ft/s (590 m/s) Reduced Charge
HC Marks 13 and 14: 2,075 ft/s (632 m/s) Reduced Charge
Effective firing range before turret refit.
AP Mark 3: 22,900-yard (20,940 m) at 15° elevation
AP Mark 5: 23,000-yard (21,031 m) at 15° elevation
Effective firing range after refit
AP Mark 3: 34,300-yard (31,364 m) at 30° elevation
AP Mark 5: 35,000-yard (32,004 m) at 30° elevation
Maximum firing range
AP Mark 3: 40,600-yard (36,700 m) at 45° elevation

As can be seen, the AU US Standard Battleships are smaller, almost as fast or faster, more heavily armored and have roughly equivalent overall gun armaments to their Japanese counterparts. Their shorter and beamier hulls roll considerably in a seaway, which necessitates firing on the clock to time the salvo to coincide with the zero of a period (about 15 seconds for a roll or 7.5 seconds via roll inclinometer). The same comparisons can be drawn for most AU US cruiser classes except that the Japanese cruisers have a marked advantage in tonnage, size, and numbers of gun barrels. When it comes to torpedo armament, it is a wash. In this AU, the Japanese do not have a crushing superiority as they do in the RTL, but all that means is that with torpedo parity, both sides will suffer catastrophically in melee combats such as Savo Island. So once again it comes down to the ship’s crews, the leadership and the training. If the RTL is any guide, the US surface fleet will have a rough time of it. The IJN will have it worse, though. US ship captains seem to have fought their ships better.

Let us look at submarines:

General characteristics
Class and type: Kaidai-class submarine (KD5 Type)
Displacement: 1,732 tonnes (1,705 long tons) surfaced
2,367 tonnes (2,330 long tons) submerged
Length: 97.7 m (320 ft 6 in)
Beam: 8.2 m (26 ft 11 in)
Draft: 4.7 m (15 ft 5 in)
Installed power: 6,000 bhp (4,500 kW) (diesels), 1,800 hp (1,300 kW) (electric motors)
Propulsion: Diesel-electric, 2 × diesel engines, 2 × electric motors, 2 screws
Speed: 20 knots (37 km/h; 23 mph) surfaced, 8.25 knots (15.28 km/h; 9.49 mph) submerged
Range: 10,800 nmi (20,000 km; 12,400 mi) at 10 knots (19 km/h; 12 mph) surfaced, 60 nmi (110 km; 69 mi) at 3 knots (5.6 km/h; 3.5 mph) submerged
Test depth: 70 m (230 ft)
Complement: 75
Armament: 6 × 533 mm (21 in) torpedo tubes (4 bow, 2 stern) up to 16 each 21 inch torpedoes carried
1 × 120 mm (4.7 in) deck gun, 1 × 13.2 mm (0.52 in) anti-aircraft machinegun

This would be the typical Japanese AU patrol submarine, based on the German WW I U-cruiser.

The AU US equivalent is a far different beast.

General characteristics (GUPPY fleet boat)
Class and type: Type 171-class submarine
Displacement: 1,870 tons (1,900 t) surfaced
2,440 tons (2,480 t) submerged
Length: 243 ft (74 m)
Beam: 32 ft 8 in (10.33 m)
Draft: 17 ft (5.2 m)
Propulsion: 1 × diesel engine with a snorkel, driving an electrical generator
SARGO type batteries, 504 cells (4 × 126 cell batteries)
1 × low-speed direct drive electric motor driving one ducted propeller
Speed: Surfaced: 18 knots (33 km/h) maximum; 13.5 knots (25.0 km/h) cruising
Submerged; 16 knots (30 km/h) for 4 hours on the battery, 9 knots (17 km/h) while snorting, 3.5 knots (6.5 km/h) cruising on battery typical
Range: 15,000 nautical miles (28,000 km) surfaced at 11 knots (20 km/h)
Test depth: 150 m (460 ft)
Endurance: 96 hours at 4 knots (7.4 km/h) submerged on battery
Complement: 9–10 officers, 5-10 petty officers 60-70 enlisted men
Sensors and processing systems:
Fessenden oscillator, the US version of ASDIC (called SONAR) and hydrophones
Mk 6 torpedo fire control system
Armament:
4 × 21.67 inch (55 cm) torpedo tubes all forward. 20-24 torpedoes carried.
1 x 3.9 in (10 cm)/L40 Model 1910 retractable deck gun with 60 rounds

This “fleet boat” is faster, deeper diving and better equipped for infiltration and ambush attacks inside an enemy coast than its Japanese counterpart. Japan’s coastline is tailor-made for this kind of boat. And that is something to keep in mind when we turn our attention to the Philippine Islands in a bit.

Good work posting a bunch of old and (sometimes) uncredited ripoffs from a Google Images search in your thread on our own forum! What are you thinking? Replace those images at once with the latest credited work available on shipbucket.com

Thanks in advance...

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USN components, camouflage colors, & reference links (World War II only)