Bingo on LEX, her damage was contained and she was underway and conducting flight operations. Better damage control WRT AVGAS bunkers and she makes it back to Pearl Harbor under her own power.
Improving the 'Graf Zeppelin' Aircraft Carrier - ship and class
- Thread starter Amartus
- Start date
Bingo on LEX, her damage was contained and she was underway and conducting flight operations. Better damage control WRT AVGAS bunkers and she makes it back to Pearl Harbor under her own power.
McPherson
Banned
Lot to deal with...
This assumes facts not often considered in this kind of discussion. The Graf Zeppelin was designed by decent engineers, who were not entirely witless. They knew how to design elevators. Their racetrack mechanical handling arrangements to feed the catapults, was a nifty way to leapfrog the plane handling arrangements for the compressed air powered cats at the bow. It allowed them to obviate the need for specialized trained flight deck plane handlers who moved planes back and forth in the spotting yoyo so common to the American, and British carriers of WW II. This arrangement of course makes sense for a ship with a slow launch cycle and a strike below aft, arm/fuel in the hanger and feed up and forward to the compressed air powered catapults op cycle. It assumes an architecture for a cramped short enclosed hanger and a small air-wing. It is AFAIK uniquely German and tries to "automate" plane handling as a mechanical process.
The tram car trolley system even extended to overhead crane arrangements in the hanger with the added benefit that aircraft were supposed to be triced on the hooks in the hanger when not in use. It is ingenious, too complicated, with too many mechanical fail points and absolutely overthought and German.
At some point, when the trolley car system breaks down or the Germans figure out how to wind over deck, the spotting yoyo comes into play. Notice on the Italian Aquila that there is a crash fence on the flight deck along with the German type trolley car feed system? The Italians had figure THAT PART out.
Now assuming the Germans balcony their AAA guns and land the 15 cm guns freeing up that deck space, one gains volume for a tertiary "storage" hanger Depending on how clever the Germans are, the aft elevator/loft becomes a two story job and more planes can be shuffled below to "park" but not service. They are queue delayed until the active cycle is complete. Maybe 15-20 folded up and stowed on standby? This could conceivably result in a 60 plane carrier. Useful if a fighter bomber method of aviation employment is enjoined.
A raider carrier has to be all beak and claws. The "fighters" have to scout, attack and defend.
a. Albacore was fine as is.
b. Joffre and Panleve have serious design faults.
c. Aquila has to overcome Il Duce. Shoot him and the Regia Marina looks a whole different kettle of fish. Italo Balb can be reasoned with. That psychopath loves aircraft and navies. Are there enough ocean liners?
Mission drives need. Unless the dictators can be sidelined and mission drives peacetime intent, then the ego-nuttery that was our RTL is what drives results. Britain (the flying club) is not immune to this nuttery.
More wing area = more lift = lower stall speed = easier wind over deck operations. It is the difference between a 15 m/s carrier in a rough seaway and a 17 m/s carrier in a rough seaway on a sustained launch into the wind speed run..
See above. Lift matters, both for the type of carrier built, endurance of the plane launched, and load carried aloft. (Albacore is a good example of what happens and why it is going on. It is an intelligent solution to a British carrier problem (slow speed into the wind runs) that is unfairly criticized.)
See above.
Again see above.
First; the S2CB Hellcat was the coffin nail for Curtiss. People think the Brewsters were terrible? This piece of junk had an inbuilt in flight stability problem that almost crippled it as a dive bomber. It was foisted on the navy anyway. Rejected because...
Second; navy pilots discovered the do-everything Avenger could dive bomb. And do that role surprisingly well.
With elbow room needed for fueling and arming the planes on the flight deck, yoyos, takeoff runs, and so forth, it matters as to how effective the weapon launch characteristics. Berthing among the democracies is a curious question. Those navies actually had legislatures pass laws prescribing square and cubic footage per man because the admirals (C&R) thought of the crew last when it came time to cram too much into too small a hull.
The crazy Russians put saunas aboard their Boomers.
It still took more and more powerful torpedoes to polish off the Yorktowns than their Japanese counterparts. Shokaku and Zuikaku being the case proofs. Yorktown took tremendous damage pre-Enterprise refit. Hornet took more torpedoes (sitting duck target) than any Japanese carrier (including the Shinano) ever could survive..
In the Douhet crazy era, that sums up everyone's problems. In the US case, the B-17 was sold by the AAF as an anti-shipping weapon to Congress. Never mind that this was mission poaching by the army air forces on naval aviation turf, (a problem which continues to this day. The B-1 Lancer is a PERFECT antishipping launch platform and LRMP for the USN. Who owns it? The USAF.). Anyway the B-17 was a high altitude level bomber with a daylight only precision bombing mission and design parameters. It needed long all weather runways to operate and it employed a large crew. It was a prototype city killer bomber. How was it supposed to hit a ship from 5,000 meters up? Only the clueless (Congress) believed the AAF lies. The AAF got their city-killer and the USN was stuck with seaplanes and carriers. Later (but only in wartime) did land-based LRMPs (Liberators, a bodged compromise) see service with both the British and American navies.
The PB4Y-2 Privateer was what should have been the naval standard.
Agreed. However, despite Goring, the Germans did manage a halfway anti-shipping answer, that had it been pushed harder (guided bomb) would have solved a lot of :"dive bombing" problems for them in the Battle of the Atlantic. Even if the FW 200s were lost at a rate of 1 plane per 3 ships per mission, it makes economic sense to try before the allies wise up and send fighters to sea.
Dedecking a carrier is a mission kill. That is what doomed the carriers lost during the first part of the Pacific war, Japanese and American.
This assumes facts not often considered in this kind of discussion. The Graf Zeppelin was designed by decent engineers, who were not entirely witless. They knew how to design elevators. Their racetrack mechanical handling arrangements to feed the catapults, was a nifty way to leapfrog the plane handling arrangements for the compressed air powered cats at the bow. It allowed them to obviate the need for specialized trained flight deck plane handlers who moved planes back and forth in the spotting yoyo so common to the American, and British carriers of WW II. This arrangement of course makes sense for a ship with a slow launch cycle and a strike below aft, arm/fuel in the hanger and feed up and forward to the compressed air powered catapults op cycle. It assumes an architecture for a cramped short enclosed hanger and a small air-wing. It is AFAIK uniquely German and tries to "automate" plane handling as a mechanical process.
The tram car trolley system even extended to overhead crane arrangements in the hanger with the added benefit that aircraft were supposed to be triced on the hooks in the hanger when not in use. It is ingenious, too complicated, with too many mechanical fail points and absolutely overthought and German.
At some point, when the trolley car system breaks down or the Germans figure out how to wind over deck, the spotting yoyo comes into play. Notice on the Italian Aquila that there is a crash fence on the flight deck along with the German type trolley car feed system? The Italians had figure THAT PART out.
Now assuming the Germans balcony their AAA guns and land the 15 cm guns freeing up that deck space, one gains volume for a tertiary "storage" hanger Depending on how clever the Germans are, the aft elevator/loft becomes a two story job and more planes can be shuffled below to "park" but not service. They are queue delayed until the active cycle is complete. Maybe 15-20 folded up and stowed on standby? This could conceivably result in a 60 plane carrier. Useful if a fighter bomber method of aviation employment is enjoined.
A raider carrier has to be all beak and claws. The "fighters" have to scout, attack and defend.
a. Albacore was fine as is.
b. Joffre and Panleve have serious design faults.
c. Aquila has to overcome Il Duce. Shoot him and the Regia Marina looks a whole different kettle of fish. Italo Balb can be reasoned with. That psychopath loves aircraft and navies. Are there enough ocean liners?
Mission drives need. Unless the dictators can be sidelined and mission drives peacetime intent, then the ego-nuttery that was our RTL is what drives results. Britain (the flying club) is not immune to this nuttery.
More wing area = more lift = lower stall speed = easier wind over deck operations. It is the difference between a 15 m/s carrier in a rough seaway and a 17 m/s carrier in a rough seaway on a sustained launch into the wind speed run..
See above. Lift matters, both for the type of carrier built, endurance of the plane launched, and load carried aloft. (Albacore is a good example of what happens and why it is going on. It is an intelligent solution to a British carrier problem (slow speed into the wind runs) that is unfairly criticized.)
See above.
Again see above.
First; the S2CB Hellcat was the coffin nail for Curtiss. People think the Brewsters were terrible? This piece of junk had an inbuilt in flight stability problem that almost crippled it as a dive bomber. It was foisted on the navy anyway. Rejected because...
Second; navy pilots discovered the do-everything Avenger could dive bomb. And do that role surprisingly well.
With elbow room needed for fueling and arming the planes on the flight deck, yoyos, takeoff runs, and so forth, it matters as to how effective the weapon launch characteristics. Berthing among the democracies is a curious question. Those navies actually had legislatures pass laws prescribing square and cubic footage per man because the admirals (C&R) thought of the crew last when it came time to cram too much into too small a hull.
The crazy Russians put saunas aboard their Boomers.
It still took more and more powerful torpedoes to polish off the Yorktowns than their Japanese counterparts. Shokaku and Zuikaku being the case proofs. Yorktown took tremendous damage pre-Enterprise refit. Hornet took more torpedoes (sitting duck target) than any Japanese carrier (including the Shinano) ever could survive..
In the Douhet crazy era, that sums up everyone's problems. In the US case, the B-17 was sold by the AAF as an anti-shipping weapon to Congress. Never mind that this was mission poaching by the army air forces on naval aviation turf, (a problem which continues to this day. The B-1 Lancer is a PERFECT antishipping launch platform and LRMP for the USN. Who owns it? The USAF.). Anyway the B-17 was a high altitude level bomber with a daylight only precision bombing mission and design parameters. It needed long all weather runways to operate and it employed a large crew. It was a prototype city killer bomber. How was it supposed to hit a ship from 5,000 meters up? Only the clueless (Congress) believed the AAF lies. The AAF got their city-killer and the USN was stuck with seaplanes and carriers. Later (but only in wartime) did land-based LRMPs (Liberators, a bodged compromise) see service with both the British and American navies.
The PB4Y-2 Privateer was what should have been the naval standard.
Agreed. However, despite Goring, the Germans did manage a halfway anti-shipping answer, that had it been pushed harder (guided bomb) would have solved a lot of :"dive bombing" problems for them in the Battle of the Atlantic. Even if the FW 200s were lost at a rate of 1 plane per 3 ships per mission, it makes economic sense to try before the allies wise up and send fighters to sea.
Dedecking a carrier is a mission kill. That is what doomed the carriers lost during the first part of the Pacific war, Japanese and American.
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McPherson
Banned
Quite reasonable, but then one has to explain Musashi. She went down and so did Yamato. Her, Yamato's, belt armor and torpedo defense unzipped early and she was doomed after several hits before internal fires set off her magazines. It is likely that design flaw was what killed Shinano and four fish might have been enough, even if she had a competent crew and watertight doors fitted.
RamscoopRaider
Donor
Yamato took 7-8 torpedoes and several bombs before she was doomed and Musashi took 10 torpedoes and 10 bombs before she was arguably doomed (both ships took more than this but that was arguably overkill). I consider it possible 4 torpedoes could have done the job, likely? Not convinced of that
McPherson
Banned
Again quite reasonable. I'm just saying the Japanese were shocked that Musashi had to be beached in that mid attack episode. Someone aboard knew they were kaput at that point. The American follow ups were a guaranteed overkill that she would not make it to shore. YMMV.
Musashi was hit by, at minimum, 19 heavy bombs (a mix of 500 and 1,000 pound SAP and 500, 1,000 and 1,600 AP) and 17 torpedoes. Her armor "unzipped" because it was directly struck by 36 ship killers plus numerous near misses. Despite that she took SIX HOURS to sink. Given the number of torpedo hits it is likely that more than half of her external hull below thewaterline was either complete gone or had suffered severe cracking (assuming a fairly conservative 40 feet of destruction diameter per torpedo hit). The ship had half of its outer hull completely destroyed (plus other damage from near miss bombs that detonated below the main belt) but didn't sink for six hours and managed to maintain engine power until roughly half an hour before her loss
Her sister Yamato was "only" hit by 12 heavy bombs and 7-8 torpedoes (having learned from the attack against Musashi all but one of these hits were on the port side, the AAR on the sinking of Musashi indicating that by striking both flanks the torpedoes had actually provided a counter flooding effect) before she capsized and sank.
Both of the Yamato class ships were bad decisions by the IJN, three or four 406mm gunned fast BB (or half a dozen carriers) would have been a far better use of resources, but the ships demonstrated remarkable ability to accept damage.
McPherson
Banned
Lt. Carter was a j.g. Avenger pilot in the third wave (based on the link you provided).
Before he arrived Yamato had already been hit by 8-10 heavy bombs and three, perhaps four, torpedoes. His brief comments indicate that his flight provided the coup de grace, but he was not there until Yamato had been getting pounded for over an hour.
How many ships actually ever survived 5 torpedo hits?
Does anybody know what's the most working torpedo hits that any ship survived? (preferably out of harbour and returned to service)
McPherson
Banned
How does that change the number of reported torpedoes or Aragi's report?
Not many.
The Seia Maru: a 6700ton (GRT) auxilliary ammuntion ship. Weird candidate; but it was at sea when reportedly hit by three US torpedoes and did make it back to port and did eventually return to service. It was eventually sunk in 1944.
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BlondieBC
Banned
Both have the same mentality because they have the same needs. Both are primarily land powers who have two military naval objectives. The first is to keep the enemy navy and more importantly amphibious forces off their coasts. If this is accomplished, the army can focus on land attacks not defending against potential attacks on the coast line. It is a shame to build a great Heer and then have 20% of them on coastal guard duty. The secondary need is to deny the ability to move merchants across the sea to their enemy. There is no need to be able to move their own merchants or amphibious ships across the sea. The British before WW1 called this the "second class navy" strategy.
I have spent a lot of time working on how the Germans should have built their navy. And generally speaking, the Imperial and to a lesser extent the Nazi navies should have built ships and planes on the Soviet plans. The Soviet Navy was what the German High Seas Fleet should have been. And what the Nazi's navy should have been. Fortunately, we can only debate how effective the soviet navy would have been in WW3. The Nazi should have only started building a carrier about 30 years into their naval rebuilding program. And in this case, the carrier purpose would probably to provide fighter coverage to it submarine or surface navy.
Every ton of steel put into the Graf Zeppelin was wasted metal. The same for the Bismark class ships. Germany need more trucks. More troop transports. More fighters. More tanks. More artillery. More track. More trains. More U-boats.
McPherson
Banned
You get it.
Or assistance to the Italians in a Mediterranean combined strategy. (See above, where I discuss the German limitations in the Mediterranean.)
More rocket propelled buzz bombs for port bombardments, more LRMPs and more anti-shipping missiles.
BlondieBC
Banned
Yep. I get it.
A month or so ago, I looked up the proposed Soviet first carrier. Look at the planes. Then said. Yep, this right. This ship only had fighters who could also scout. And could also do some attack role. The purpose of a wise Graf Zeppelin would be to keep Swordfish at bay. To scout for ships. To sink thin skin ships such as DD or merchies. And mainly to give the royal navy fits in counter the Graf Zeppelin in thinking about the ship. But there is a problem. The soviets had great land based naval aviation. A large submarine force. Well balance surface navy. The proposed soviet carriers would create a giant circle where NATO long range attack planes could not operate without significant shorter range fighter protection. The problem for the Nazi's is they had no good, land-based long range medium or heavy bombers with guided weapons. The did not have that many subs starting the war. And the Nazi surface fleet was not competitive even if I assume the British refuse to use war planes.
And then I looked at Calbear CVL post. Even if I assume the Nazi have the same tonnage, but in American CVL. It does not help. Even if the Nazi have them at the start of WW1. Pointless in conquering Poland. Probably saves a few ship losses in taking Norway, and sinks a few British ships. The British have plenty of warships. I guess maybe the carriers can win the sea battle at Dunkirk, but the CVL would have trouble staying that close to England for very long. Then what. Attack Leningrad in late June 1941? Total waste of resources. Then in 1942. Can't sink enough convoys to break the back of Soviet land forces.
I have not done much reading on Italy in WW2. Either land or naval issues. My overall impression is the Italians under performed. And my impression is the only way for Germany to help is with land based naval aviation. And this is one of the reason I love naval air power as soon as it available, even if it is Zeppelins. When I imagine Germany spending the Graf Zeppelin funding on a few squadrons on quality naval aviation, I see opportunity. And to be fair, this is how the Graf Zeppelins squadrons will be used. If we imagine 2 squadrons fighters, 2 squadron dive bombers, 2 squadron torpedo. All certified for carrier landings. I get a powerful and flexible tool. These units might well be able to cut off the evacuation of Dunkirk. Depending on how fast air bases could be capture, might be very useful in Norway. Might be very useful with Army Group North in 1941. If moved to the Med, they are hugely useful. Malta could be isolated. UK shipping loses increase. Put half these squadrons in Sicily, half in Tunisia. It gives the UK fits. Depending upon range, squadrons in Crete might be hugely useful. Depending upon the speed of redeployment, they might be very useful in dealing with Torch.
And yes, I think the Germans lost an opportunity not pushing glide bomb development.
And plane are cheap compared to capital ships.
McPherson
Banned
1. Italian naval thinking permeated Russian naval thought.
2. The Americans had an answer for both the cold war Russian submarine fleet and their nascent carriers. This would be their own submarine force which was quite deadly. Soviet ASW was not too good.
3. Raiding does not win naval wars. Use of the sea does. And if a seapower cannot use the sea, it generally loses the whole war. That is Mahan. The submarine and the aircraft does not allow its users to use the sea, but those weapons platforms can deny. Sometimes that is good enough. The American Revolution succeeds because France can deny Britain the use of the seas along the North Atlantic and along the Indian coasts. Britain can save one enterprise, but not both. She chose India. (Mahan). So we have a United States.
Better invest in diplomacy (Japan) and LRMPs.
The only way the Germans can help Italy in the PoD's proposed is tech transfers and resource support.
Italy needs the resource basics, food, fuel, steel.
Tech support comes in the form of licensed items and tech crossovers; from Germany a machine gun, aviation engines, tank destroyers, grenades, and maybe a tank line. From Italy, Germany could use explosives, torpedoes (Italian tech finds it way into US WW II torpedoes!) anti-shipping tactics.
As for Italian armed forces being underperforming? Top down rot down. The Italian soldier did not believe in the war. This affected his performance a bit. HOWEVER, the professionalism and the courage and the skill when they did fight; land, sea and air was second to none. Their technology and their political leadership failed them. France and Russia suffered the same debilitation. Nobody usually, if he is objective, complains about them.
Not cheap, just quicker to produce and replace as expendable attrition units.
It doesn't, but your post referred specifically to Lt. Carters report and made no mention of Captain Aruga.
The link also somehow divines what Captain Kosaku Aruga's thoughts were during the attack despite the fact that he, in true IJN tradition, lashed himself to wheel of his command and went down with his ship meaning there is no record of his thought during that time. Based on the time given in the link you provided, 14:10, the Yamato had already received 12 bomb hits and 7-8 torpedoes (the AAR from 2nd Destroyer Squadron for Ten Ichi indicates that Yamato sank at 14:17, six minutes earlier than TF 58 records).
The final few torpedoes mentioned were the ones that struck the ship after she had heeled far enough onto her beam that they struck the bottom of the hull (having been set to run 20 feet below the surface). IJN records and post war interviews by the USSBS (Pacific) also indicate that the counterflooding described as occurring at 14:10 actually took place between 13:30 and 13:35.
McPherson
Banned
And that still means 5 did her in.
"The final few torpedoes mentioned were the ones that struck the ship after she had heeled far enough onto her beam that they struck the bottom of the hull (having been set to run 20 feet below the surface). IJN records and post war interviews by the USSBS (Pacific) also indicate that the counterflooding described as occurring at 14:10 actually took place between 13:30 and 13:35."
https://scout.com/military/warrior/Article/How-the-Japanese-Yamato-Battleship-Sank-WWII-101459563
Better source.
"The final few torpedoes mentioned were the ones that struck the ship after she had heeled far enough onto her beam that they struck the bottom of the hull (having been set to run 20 feet below the surface). IJN records and post war interviews by the USSBS (Pacific) also indicate that the counterflooding described as occurring at 14:10 actually took place between 13:30 and 13:35."
https://scout.com/military/warrior/Article/How-the-Japanese-Yamato-Battleship-Sank-WWII-101459563
Better source.
So the multiple bomb hits and additional torpedoes, which had struck before the final wave that included Lt. Carters, did no damage?
The issue here seems to be the focus on five torpedoes. There were three waves that struck Yamato, none of them separately put five torpedoes into her. Combined, and including the unnecessary final three that hit the bottom of the hull due to her ever increasing list, a total of 10-11 torpedoes hit the ship, so 7-8 were responsible for her sinking, along with massive bomb damage from direct hits and near misses). The number of torpedo hits jumps from 4 to 7-8 during the attack of one four aircraft section. There is no way to determine if hit five was the lethal blow, or if it was six, or finally seven/eight.
This most recent source pretty much confirms everything we have been saying (although it has a lower number of heavy bomb hits than most records and AAR indicate), that the ship sank as the result of accumulated damage over a series of strikes that lasted less than two hours.
BlondieBC
Banned
2) We don't really know if the USA had an answer for Soviets fleet. We would need a war to see who had the right strategy. And there is also an ebb and flow of strategy and counter strategy. As technology, diplomacy, and resources change over time; we tend to see one or the other become dominant in an alternating pattern. Soviet gets better bombers, USA gets better carrier based fighters with better air-to-air missiles. Soviet improve missiles more, USA build AEGIS ships.
3) Raiding can win naval wars. WW1 was winnable by German raiders if you an avoid bringing the USA into the war. WW2 is winnable with raiding if the USA stays out. WW2 is also winnable at sea for the Germans before the USA enters the war. You also look to Russia in the Black Sea in WW1 to see a successful denial of the sea win.
3A) Mahan can be a mental trap. His work is good, but his strategy is not the only good strategy available. And no one ever executed a pure Mahan strategy. They all the 'Mahan' naval nations made significant changes.
While the Italians do need resources and tech support, there is a big naval benefit that can be done. IOTL the Germans transferred about 60 planes or so to the Sicily. Just plane old BoB type fighters. The war went much better. So obviously transferring more fighters, some stuka, and patrol craft would have been a big help. One never knows which German plane might fight the carriers coming to attack Taranto. Or just deter the attack entirely. Or damage enough additional UK ships to deter.
Back to the original POD. I think they have the workup on the Graf Zeppelin staring about mid 1942 with operational status in mid 1943. This implies that the squadron is fully trained on non-carrier landing skills by mid 1942. Probably means we start working up the squadrons in mid 1940. Maybe a year earlier. These squadrons should be combat effect from airstrips by mid-1941 at the latest. These squadrons can be sent to the Med to help the Italians while the ship is being built.
The glide weapons are cheap. Cheap in a war is not an absolute term but must always be compared to the other side resources consumed. The full additional R&D plus producing a few thousand of these weapons is well below the cost of single British capital ship. And maybe below the cost of a handful of cruisers. The planes and the rest of the needed weapons existed. So if one imagine a push to develop these weapons in the 1930's instead of buildings some other naval assets, the expected result of using a 1000 or so of these weapons instead of gravity bombs is multiple capital ships, a few cruisers, a few dozen DD and similar ships and probably a score or two of merchant ships. Say 50 ships in worse case scenario, maybe as high as 100 ships. The low end is well above the best case scenario for both Bismarck class ships.
I know we're going off in a 'lil bit' of a tangent here with the Yamato sinking, but has anyone seen this movie?
Its far from accurate in regards to the final sinking with the Shanshiki shells downing US aircraft and the protagonists shooting down more planes alone than the US lost that day. But the attack itself is rather well done, although the US aircraft, in addition to strafing appear to be firing rockets at the Yamato which would make sense as they would supress her AA guns. Also the work on the 25mm mounts is actually VERY accurate. The IJN's 25mm gun was a complete pig of a weapon, and as they had nothing better they just 'solved' their AA problem by adding more of these exceptionally medeocre weapons to their ships. In the action scenes you see the loaders pushing down on the ammo boxes, that was SOP as the gun had a habit of bucking the ammo boxes out of their housing. And due to them being clip fed, when you see them firing one or two barrels on the triple mount instead of all three, again this was what they were taught. That way you'd have one gun loaded with ammo whilst the other two were reloaded. Its very nice accurate touches like this, as well as the pre-battle stuff where we get to know our protagonists and you see the very harsh life of the sailors in the IJN at the time that make up for the historical inaccuracies.
Its far from accurate in regards to the final sinking with the Shanshiki shells downing US aircraft and the protagonists shooting down more planes alone than the US lost that day. But the attack itself is rather well done, although the US aircraft, in addition to strafing appear to be firing rockets at the Yamato which would make sense as they would supress her AA guns. Also the work on the 25mm mounts is actually VERY accurate. The IJN's 25mm gun was a complete pig of a weapon, and as they had nothing better they just 'solved' their AA problem by adding more of these exceptionally medeocre weapons to their ships. In the action scenes you see the loaders pushing down on the ammo boxes, that was SOP as the gun had a habit of bucking the ammo boxes out of their housing. And due to them being clip fed, when you see them firing one or two barrels on the triple mount instead of all three, again this was what they were taught. That way you'd have one gun loaded with ammo whilst the other two were reloaded. Its very nice accurate touches like this, as well as the pre-battle stuff where we get to know our protagonists and you see the very harsh life of the sailors in the IJN at the time that make up for the historical inaccuracies.