American militarism pre-WW2 and the Ultimate Battleship

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TheMarcksPlan
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by TheMarcksPlan » 22 Feb 2021 04:15

Just by the by... Another potential benefit of using structural steel as armor:

The guns are mounted on pinions placed directly in the turret face, which is ~4ft thick. I've done the calculation on recoil force and the compressive strength of steel (can reproduce calculation here if someone asks nicely). Long and short is this frees up more turret space and we can actually reduce recoil distance due to the enormous strength of a ~4ft thick steel slab. Reduced recoil further frees up turret space (shorter distance between tray and breech) and can cut maybe .3 seconds off cycle. That aspect isn't part of the turret side-view I posted far upthread but is a reserve if needed.

Another thing from a prior post:
T.A. Gardner wrote:The gun is then fired when the ship reaches a level position in roll, pitch, etc., as the gun isn't stabilized. This ensures a more accurate shot.
This is true but on megaship would be massively mitigated:
  • The ship's linear dimensions are ~4x as great as Iowa's. 10ft waves on megaship have the impact of 2.5ft waves on Iowa; 2.5ft waves are likely statistically insignificant.
  • The megaship would be fin-stabilized. First used in 1933, fin stabilizers are more effective with the square of speed as they operate by generating asymmetric lift. A megaship doing 40kn would be very efficient to stabilize.
  • A 0.1 degree elevation error for a 45 degree shoot (megaship's preferred range) causes a 0.0003% range error.
For those reasons, megaship would in most conditions not experience statistically-significant firing delay due to roll/pitch. Were roll significant, fin stabilizers would shrink the roll-period on a fast-moving megaship (e.g. a megaship shooting at airplanes).
https://medium.com/counterfactualww2
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by TheMarcksPlan » 22 Feb 2021 05:42

TheMarcksPlan wrote:Of course we don't want to compress the powder sufficiently to ignite it. I don't know what that limit is but intuitively seems far afield of a slight squeeze in the chamber
Well my powder-compression intuition is a bit off. After writing the above, recalled:

https://en.wikipedia.org/wiki/USS_Iowa_ ... on#Overram
https://medium.com/counterfactualww2
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by TheMarcksPlan » 22 Feb 2021 06:44

Re the issue of bags falling out at 45 degrees, we don't even know if this would actually happen. Iowa loaded at 5 degrees, if bags were frictionless they'd fall out at that angle anyway. So we have an empirical issue of bag friction.

Even if bag friction in the default case is insufficient for 45 degrees, I don't take the objection seriously because there are multiple solutions easily feasible. Last bag has a foam outer edge that can be compressed, for example. Worst case you just use a brass base charge as the Germans did in all their big guns.

The issue of shells falling out I don't take seriously at all: as stated already, every high-angle gun relies on metal-metal friction to hold shells in place well above megaship loading angle.
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by TheMarcksPlan » 24 Feb 2021 04:23

Had the ship existed in late '41, and the Japanese somehow not been deterred, I could see the following career:

December 7, 1941: In Tacoma, the likely place for its West Coast facilities.

January 1, 1942: Boards 4 divisions and their vehicles + supplies, 1,500 planes (400 P-38ish craft, 200 B-25ish, 400 SBD's, 200 F4F's, 300 Avengers).

January 1-7, 1942: Sails to Corregidor (quay built there for it), destroying shipping and isolated warships with AC on its way while avoiding battle due to its cargo.

January 10th, 1942: Having reinforced Philippines, destroys all shipping in South China Sea with its AC, halting Japanese advance towards Singapore.

February 10th, 1942: After megaship has rampaged across forward Japanese positions, isolating its armies and outposts, IJN's honor compels it to sail en masse against a megaship that has begun launching attacks on the Home Islands. Megaship uses its long-range P-38ish craft (and naval intel) to maintain full awareness of Japanese forces at sea.

February 11th, 1942: Megaship attacks the Japanese aircraft carriers, maintaining ~200nm distance from strong IJN forces. First wave: 300 P-38's to clear the skies ahead of the strike. Second wave: 200 B-25's who loiter until the second wave is in the air. Third wave: 300 SBD's/Avengers. Result: Kido Butai sunk. Successive strikes on the IJN surface fleet steaming towards megaship, who maintains distance throughout the night.

February 12th, 1942: Megaship reverses course, gets between IJN fleet and Home Islands, begins shooting 5,000 18in rounds/minute into the formation from 48,000 yards. After 15min ceases fire. Only scattered ships still afloat. Disengages, begins launching AC to finish remnants of IJN.

February 18th, 1942: Back in Tacoma. Minor repairs superficial damage.

March 6th-10th, 1942: Air raids on Home Islands, focusing on shipping and remnant IJN in Tokyo Bay and Inland Sea. Bombards and annihilates steel factory at Hamamatsu. CAP and AA shoot down hundreds of Japanese planes. Hit by submarine torpedo, one shaft lost, speed reduced by 0.5kn.

March 10th-12th, 1942: Yellow Sea. More shipping destroyed. Two more hits from submarine torpedoes. Reserve buoyancy decreased by 3,000 tons (0.3%).

March 16th, 1942: Bombards IJA on Luzon in support of American counteroffensive. Temporary repairs in Manila.

Remainder of March, 1942: Air raids against Japanese bases in SW Pac, heavy bombardment of Turk and Palau. Facilities leveled.

April 1942: Patched up in Tacoma; damaged shaft removed but, to save time, not repaired. Max speed permanently limited to 39.5kn.

May 1st, 1942: Transferred to Atlantic Fleet.

May 20th, 1942, Morning: Appears off of Brest at first light, fires 100,000 AP shells at U-boat pen, 10,000 hit, structure effectively useless. Leaves at 0900, launching air cover.

May 20th, 1942, 1200: Arrives off Lorient, same as Brest. Uboat pens functionally destroyed, collapsing concrete destroys occupants.

June-October, 1942: Moves all available U.S. troops/vehicles to Britian from Provincetown facility to newly inaugurated deepwater quay in Firth of Clyde (FDR told Churchill to start building in 1940).

October 21, 1942: Helps escort convoy to Malta, air raids on Sicily.

October 23, 1942: Appears of El Alamein at first light. Drops 500,000 tons of shells on 25 miles of Rommel's left flank. Monty breaks through in the north, hooks left to trap Rommel against the Qattara Depression. Rommel captured, DAK finished.

October 24, 1942: Sails back through Sicilian Narrows. Mined twice. Reserve buoyancy decreased by 0.6%.

October 25- November 2, 1942: Operates in Tyrhenian Sea, shutting down shipments from Italy to Africa with aircraft. AA, CAP, fighter sweeps destroy most of LW in the area. Sardinia focus to eliminate any LW danger to Torch. Kesselring decides not to attack megaship after a few days but has already lost most bombers futilely. Air raid on La Spezia knocks out most of Italian fleet. Torpedo'd again (reserve buoyancy down by 0.9%).

November 3-7, 1942: Patched up in Gibraltar, picks up ammo left there on previous transatlantic run.

November 8th, 1942: Sails ahead of Torch fleet. With LW seriously weakened and most of Italian fleet destroyed, Americans consent to advance the eastern task force to Bone. Megaship covers landings, patrols narrows with planes. Many small craft and mine-layers sunk. Axis aerial and surface transport interdicted. Tunis falls during November, Axis never gets over a significant fighting force and Rommel's forces are already destroyed.

Remainder of November: Two trips to move US forces to Britain.

December 1942: Supports landings on Sicily, bombards Axis "flak fortress" and other installations at Messina when they try to evacuate. All Axis forces captured. Bombards Rome. Italy surrenders.

Winter-Spring 1943: Moves American forces to Britain.

May-July 1943: Shore bombardment in support of Roundup, then continues moving forces to Europe.

August 1943: Transferred back to Pacific.

Remainder of war: Maintains blockade of Japan, moves U.S. forces to Pacific when necessary.

---------------------------------------

War in Europe over by Spring '44, Japan never gets Indonesian oil and loses navy in early '42. Maybe same VJ date as OTL with a siege until the A-bombs. But many fewer American deaths.

Alternative story would involve Sledgehammer '42 enabled by the megaship moving 40 divisions to Europe. That requires America to have built a larger army, which is feasible given ATL conditions.
https://medium.com/counterfactualww2
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by Richard Anderson » 24 Feb 2021 08:27

TheMarcksPlan wrote:
24 Feb 2021 04:23
Had the ship existed in late '41, and the Japanese somehow not been deterred, I could see the following career:

December 7, 1941: In Tacoma, the likely place for its West Coast facilities.

January 1, 1942: Boards 4 divisions and their vehicles + supplies, 1,500 planes (400 P-38ish craft, 200 B-25ish, 400 SBD's, 200 F4F's, 300 Avengers).
I'm sorry, but I really have to ask, how much do you drink before you post this kind of stuff? :lol:

The USAAF had 69 P-38 on hand on 31 December 1941 and no other ish in that role. They had 151 B-25. I'm not sure the Navy had 185 SBD operational, let alone 400, but they could probably just manage the F4F by stripping the entire fleet. 300 Avenger? Uh, it first flew on 7 August 1941 and the first production TBM rolled off the line in January 1942.
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by TheMarcksPlan » 24 Feb 2021 10:04

Another poster - bored and bitter in his retirement, seething in resentment about What If's in general - makes a point about plane numbers to which the response is so painfully obvious that one hesitates to respond at all.

Can anyone guess the answer?

Yes, that's right - obviously. A more militaristic USA willing to spend a few billion on a battleship/carrier doesn't build the same planes (number and/or type) as OTL.
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by Terry Duncan » 24 Feb 2021 11:52

TheMarcksPlan wrote:
24 Feb 2021 10:04
Another poster - bored and bitter in his retirement, seething in resentment about What If's in general - makes a point about plane numbers to which the response is so painfully obvious that one hesitates to respond at all.

Can anyone guess the answer?

Yes, that's right - obviously. A more militaristic USA willing to spend a few billion on a battleship/carrier doesn't build the same planes (number and/or type) as OTL.
Maybe a few less of the personal comments even if in humour?

The problem is that this idea is so far out and unworkable that people are going to point out holes. The money, the steel, the planes etc. Why do you think nobody has built a ship of such size even today? Maybe looking at a ship design simulator would be of use to you? There at least one still freely availble as far as I am aware, you may find it useful?

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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by Peter89 » 24 Feb 2021 12:15

Such concentration of force is simply not sensible; even if the megaship is built and invincible, it cannot be in two places at once. Thus, even the most imbecile naval officier would see the solution: evade the megaship, and strike where it isn't.

Weapon systems in WW2 were extremely prone to mechanical failures. The bigger and more complex they were, the more prone to failure they've become. The repair problem with the OTL sized capital ships existed already; such a ship could hardly be serviced at too many points of the world, thus limiting its operational capacity.

It was somewhat like the German super heavy program; the maus and other megatanks were invincible on paper, but what happens if they have to cross a bridge / river?

Mechanized warfare was much more about simple maintenance, easy repair, cheap replenishment, versatile deployment, etc. than about absolute power.

For example, if you could choose between 1 carrier which could carry 200 planes or 2 carriers which could carry 100 planes each, the latter is almost always the better option.
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by Terry Duncan » 24 Feb 2021 12:26

Peter89 wrote:
24 Feb 2021 12:15
Such concentration of force is simply not sensible; even if the megaship is built and invincible, it cannot be in two places at once. Thus, even the most imbecile naval officier would see the solution: evade the megaship, and strike where it isn't.

Weapon systems in WW2 were extremely prone to mechanical failures. The bigger and more complex they were, the more prone to failure they've become. The repair problem with the OTL sized capital ships existed already; such a ship could hardly be serviced at too many points of the world, thus limiting its operational capacity.

It was somewhat like the German super heavy program; the maus and other megatanks were invincible on paper, but what happens if they have to cross a bridge / river?

Mechanized warfare was much more about simple maintenance, easy repair, cheap replenishment, versatile deployment, etc. than about absolute power.

For example, if you could choose between 1 carrier which could carry 200 planes or 2 carriers which could carry 100 planes each, the latter is almost always the better option.
Yes, and with ships we have the 'internal vs external belt' argument, as the former offers better prospects until it comes to repairs.

Then again, there is a mega carrier, probably a megaship per ocean, and a mega mega floating repair dock to service them all.

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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by danebrog » 24 Feb 2021 12:53

Peter89 wrote:
24 Feb 2021 12:15
It was somewhat like the German super heavy program; the maus and other megatanks were invincible on paper(...)
Hip, hip, horray!
From Tiger to Maus to Ratte....and in the end it was puny tanks like the Hetzer that did the job
The same can be roughly applied to the navy: One is building a mega-giga-carrier - the other is building hundreds of submarines....
You don't even need to sink the supership, it's enough to send it to the shipyard for months for neccessary repairs.
Supercarrier gone - the other side suddenly has tens of submarines free for other uses....
Battles are won with tactics, wars with the slide rule

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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by TheMarcksPlan » 24 Feb 2021 13:08

Terry Duncan wrote:The problem is that this idea is so far out and unworkable
Thanks for the even-handed hosting. ;)

I mean I get the intuitive reaction; the point of the thread is to avoid grabbing our nearest intuition and to drill down on analysis of factors that make ships go/float/fire/survive/destroy.

Do you still believe that a 6:1 L:B ratio precludes high speed, regardless of Froude Number?
Terry Duncan wrote:that people are going to point out holes.
Honestly, Terry - where have I been resistant to good critiques of the idea? Our discussion of the Tall Boy/Grand Slam made me revise the deck armor specification straight away.

What I don't appreciate is replies that are just so obviously shallow they seem to be in bad faith. On what I concede is at least a $2.5bn megaship program, pretending that America would forget to spend a few million on extra airplanes for it is risible. It's the kind of unproductive, tiresome objection that is one the worst sides of this board (a board that has a lot of good things and to which I've recently chipped in money). At some point I get sick of pretending that bad faith objections need to be taken seriously and have to treat them humorously.
Terry Duncan wrote:Maybe looking at a ship design simulator would be of use to you?
Any suggestions?

As I said upthread, though, I don't always trust these simulators. If they're based on the fundamentals of ship design, great. If they're based on rules of thumb, no thanks.
Peter89 wrote:Such concentration of force is simply not sensible; even if the megaship is built and invincible, it cannot be in two places at once. Thus, even the most imbecile naval officier would see the solution: evade the megaship, and strike where it isn't.
That's fine for your navy but not for the merchant fleet and attack transports whose path the navy is to clear.

If megaship forecloses Japanese invasion and trade routes in December 1941 - by patrolling the South China Sea for example - what does Japan do? Give up on getting oil?

You're not connecting the tactical to the strategic:
Even the most imbecilic naval officer would know that the Navy had thereby lost the war, even if it never lost (always avoided) the battle. Brilliant tactic if you ignore every strategic reason for having a navy in the first place.

Likewise for your "two places at once" point: ending Japanese expansion the second it starts is a sufficient justification for megaship.
Peter89 wrote:Weapon systems in WW2 were extremely prone to mechanical failures.
Ok. One of 16 turrets goes down you fix it or, in a pinch, go without it. Same with one of 40 propellers.

In fact that's one reason the megaship possesses excessive strength: it's intended to remain operational even when part of its capabilities have been damaged.
Peter89 wrote:It was somewhat like the German super heavy program; the maus and other megatanks were invincible on paper, but what happens if they have to cross a bridge / river?
It's a bad analogy. Economies of scale are virtually inexhaustible at sea; not so for land vehicles (as you say, opposite is true).
Peter89 wrote:Mechanized warfare was much more about simple maintenance, easy repair, cheap replenishment, versatile deployment, etc. than about absolute power.
No idea how statements about "mechanized warfare" (presumably land-based) relate to naval analysis in any form compelling in this discussion.
Peter89 wrote:For example, if you could choose between 1 carrier which could carry 200 planes or 2 carriers which could carry 100 planes each, the latter is almost always the better option.
All else being equal probably so. All else is not equal. Carrier ops points addressed upthread: viewtopic.php?f=11&t=245048&p=2324590&h ... r#p2324590.
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by TheMarcksPlan » 24 Feb 2021 14:11

danebrog wrote:ne is building a mega-giga-carrier - the other is building hundreds of submarines....
You don't even need to sink the supership, it's enough to send it to the shipyard for months for neccessary repairs.
As I don't know you, don't know what level of knowledge you're working from. So this might be condescending but... Submarines are slow and have trouble catching fast ships. Queens Mary and Elizabeth crossed an Atlantic always full of hundreds of German subs and were never hit once.

Megaship takes on around a million tons of ballast to reach battle draught. If we generously assume 2,000t flooding per torpedo hit, 500 torpedoes would only relieve megaship's captain of ballasting the ship. Another 500 torpedoes would reduce her freeboard by ~1/3 to 52ft. Another 500 torpedoes and she probably needs to break off and visit the yard.

-----------------------------------------

There's a recurring phenomenon in this thread: folks who say the megaship is too big to build analyze her as if she's not that big. It's intuitive thinking rather than engagement with my numerical analysis. That's fine, I can't ask everyone to go on a deep dive in ship theory with me. But just know that, like an iceberg or full-draft megaship, there's more here than meets the eye intuitively.

She may be too big to build. But if she's not, she's almost certainly too big to sink.
https://medium.com/counterfactualww2
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by Richard Anderson » 24 Feb 2021 18:06

Terry Duncan wrote:
24 Feb 2021 11:52
TheMarcksPlan wrote:
24 Feb 2021 10:04
Another poster - bored and bitter in his retirement, seething in resentment about What If's in general - makes a point about plane numbers to which the response is so painfully obvious that one hesitates to respond at all.

Can anyone guess the answer?

Yes, that's right - obviously. A more militaristic USA willing to spend a few billion on a battleship/carrier doesn't build the same planes (number and/or type) as OTL.
Maybe a few less of the personal comments even if in humour?

The problem is that this idea is so far out and unworkable that people are going to point out holes. The money, the steel, the planes etc. Why do you think nobody has built a ship of such size even today? Maybe looking at a ship design simulator would be of use to you? There at least one still freely availble as far as I am aware, you may find it useful?
Or perhaps the real problem is this what if is yet another excuse for trolling? Remember the "let's fill in the English Channel" exercise?

Yes, indeed I'm happily retired, which means the last time I indulged myself in such fantasies, pretending it might have been reality, was 50-odd years ago when I was in the 7th grade. Heck, I even had a good friend with artistic talent that could turn our neato ideas into cool line drawings. They usually ended up looking like this https://en.wikipedia.org/wiki/Space_Battleship_Yamato I can only imagine what boredom and bitterness a non-retired legal-beagle must feel in order to have the urge to serially spam this site with such tripe.


So perhaps the real problem is this "historical research site" allowing juvenile fantasy to pose as a legitimate what if?

Sure, the United States, wracked by the Great Depression and deeply isolationist, decides to sink a few billion on a movable island. Which means millions on aircraft that haven't flown yet is chicken feed. So why don't they spend a billion more for a fusion reactor as power source? We don need no stinkin turbines. Let's add some giant impellers so it can fly. Let's add rockets, Goddard after all, so that the 16-inch guns can be supplemented with ICBMs.
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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by danebrog » 24 Feb 2021 19:18

What I was hinting at with the example of submarines (and/or bombers, for that matter): It was not about sinking, but about constant attrition.

I don't want to deny your concept, on the contrary, the idea of floating islands has its charm. (It´s just a WI after all)
And my shipbuilding expertise is not worth mentioning, but logistics issues are a bit different.
Ensuring operational capability requires certain maintenance intervals (at least for the propulsion systems).
You can ignore that, of course, but then the ship will eventually look like the Valdez in Waterworld.

And if the mega-ship operates at the speed of a QE (in order to avoid being a target for slow submarines), it needs insane amounts of fuel. Really INSANE amounts....Which, by the way, also has a negative effect on the performance and life expectancy of the propulsion system.
I would honestly be interested in an approximate calculation just to ensure the necessary fuel requirements from an operational point of view
It may sound nerdy, but I find such aspects interesting.

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Re: American militarism pre-WW2 and the Ultimate Battleship

Post by TheMarcksPlan » 24 Feb 2021 20:21

danebrog wrote:I would honestly be interested in an approximate calculation just to ensure the necessary fuel requirements from an operational point of view
It may sound nerdy, but I find such aspects interesting.
It's totally nerdy, which is totally the intended point of this thread. I was hoping to talk more about specific fuel consumption and Froude Numbers than anything else.

So for the megaship to operate in a sustained manner as a cargo transporter (after destroying Japan's navy and merchant marine, for example, after which the Pacific part of the Pacific War is mostly over and the theater goes into quiet siege):
  • At max speed, megaship uses 3mil HP to do 40kn.
  • To figure HP at reduced speed, good estimate is ((speed-RPM delta)^3) * (Wave factor) ---- Here wave factor is the proportional decline in wavemaking resistance's share of total resistance.
  • For 33 knots, I estimate a wave factor of 5%, thus HP = ~1.6mil.
  • Megaship is going to have diesels for cruise and auxiliary generation, turbines for highest speed. About 2mil HP of each. For our transporter ops, we'll run on diesels.
  • Diesel SFC at this time was around .35 lb/HP-hr. Therefore 250 long tons per hour, 6,000 tons/day, ~7.6 tons/nautical mile.
Note that, as the megaship ballasts close to a million tons to reach 110ft draft, we could also specify oil instead of ballast. By the above calculation, a million tons of oil would give the megaship ~130,000nm range at 33 knots. And/Or the megaship could act as fleet oiler.
daneborg wrote:And my shipbuilding expertise is not worth mentioning, but logistics issues are a bit different.
Logistics is fascinating. A "What If" that's incubating: What If US had invented containerized and RoRo shipping before WW2? IMO it removes many of the shipping constraints on American power projection, easily enables landing in France in '43 or earlier. Maybe gets the US Army into unnecessary trouble on the Japanese home islands.
daneborg wrote:Ensuring operational capability requires certain maintenance intervals (at least for the propulsion systems).
True. As megaship has is using ~80% of diesel HP in our 33kn example, it can keep 20% of its generators off line at all times. As there's enormous room to accommodate maintenance personnel and spare parts, I'd guess much maintenance can be done under way.

As the remaining 20% may not be sufficient for onboard hotel power draw, we may have to reduce speed to 30kn at times or - in a pinch when a tight cargo schedule demands making up lost time - activate a boiler/turbine set or two.

It all goes back to the magic of square/cube dynamics, Reynolds numbers, and Froude numbers, all of which make propelling a superlarge ship super efficient per ton, thereby making spare propulsive capacity relatively cheap.
daneborg wrote:What I was hinting at with the example of submarines (and/or bombers, for that matter): It was not about sinking, but about constant attrition.
Yeah I get that. But the ship's ability to be suffer damage without material impact on its combat capability is one of the virtues of designing an over-large ship. It's one of the reasons every iteration of the megaship has seen the benefit of combat draught only after taking on ballast: That ballast is a "damage reserve" whereby you're pinpricking a ship that intends to half-sink itself before battle anyway. Among other things, it means that torpedo and diving-shell hits during battle cause no immediate list, unlike other ships for which the primary non-survival goal of damage control is to counterflood against list, thereby preserving aiming accuracy and combat effectiveness.

This means that a megaship that has even dozens of holes in its hull can continue operating, continue seeking the next battle. It need go into the yards only when its combat capability has been eroded by damage exceeding its ballast allowance (as estimated upthread, up to 500 torpedoes - though fewer if it loses shafts).
daneborg wrote:(It´s just a WI after all)
Normally this would get my hackles up haha. Within WI's there's counterfactual reasoning, which seeks to test a historical narrative by examining the absence/reversal of the supposed causal factor. IMO that's a intellectually valid form of analysis with primacy of place in empirically-oriented social sciences and improperly undervalued by historians.

This What If is a bit different in that I'm not necessarily suggesting that the historical conditions for megaship's construction were feasible.

At its heart, the inquiry is this:

The US possessed the economic means to "bully" other seapowers prior to WW2 but for many reasons did not exercise it (we certainly did only ~5 years later though, and continue to do so today). When we chose to swamp potential naval challengers with our industrial might, we did it mainly via quantity. Our ships were as good any others but not qualitatively anomalous to the degree that our quantity was anomalous (of all major fleet and support types by the end of WW2 and ever since).

Had we chosen the path of qualitative anomaly along with quantitative, IMO it's inevitable that we would have built battleships larger than other powers' battleships - not merely more of them. This was indeed the path we followed in the supercarrier era. IMO this would have been the right path for a prewar hegemonic USN, given the inexhaustible economies of scale for ships (square/cube, Froude number, Reynolds number, water pressure at depth).

Whether pursuing qualitative superiority via scale would have looked exactly like this megaship is, of course, open to debate.
https://medium.com/counterfactualww2
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