Alaska Class vs. Des Moines Class for the Postwar World?

[Delta Force]

The Alaska class battlecruisers possessed greater firepower than a heavy cruiser while having comparable crew complement and horsepower output (and thus likely fuel consumption). They were also completed before the Des Moines class heavy cruisers, with two of the ships seeing combat service during World War II and one being launched shortly after its conclusion. Why did the United States decide to put the combat proven but otherwise new Alaska class battlecruisers in reserve while going on to complete three Des Moines class cruisers with complicated (but we now know successful) autoloading turrets several years after the War? Were the ships a victim of their unusual caliber main armament, or was it something else?

Iowa class battleship
-- Complement: 2,700
-- Horsepower: 212,000

Alaska class battlecruiser
-- Complement: 1,517 or 1,799 or 2,251 (middle value same as the Des Moines)
-- Horsepower: 150,000

Des Moines class heavy cruiser
-- Complement: 1,799
-- Horsepower: 120,000

Baltimore class heavy cruiser
-- Complement: 1,146
-- Horsepower: 120,000

Worchester class light cruiser
-- Complement: 1,560
-- Horsepower: 125,000

Cleveland class light cruiser
-- Complement: 1,255
-- Horsepower: 100,000

 

[torten]

Cost. Des Moines class would be cheaper to operate. Still, the Alaska class could have the crew cut down quite a lot if US Navy was prepared to only have one turret in operation, and only have partial AA available, though if the money was available they could be given Terrier SAMs.

 

[Carl Schwamberger]

Does not CalBear have a opinion on this?

 

[Delta Force]

Cost. Des Moines class would be cheaper to operate. Still, the Alaska class could have the crew cut down quite a lot if US Navy was prepared to only have one turret in operation, and only have partial AA available, though if the money was available they could be given Terrier SAMs.

I forgot to put this in the original post for some hard numbers (will edit it in), and there are some differences between wartime and peacetime crew complements, but the numbers for the Alaska class are much closer to the autoloading light and heavy cruisers than the battleships, and those autoloading ships were completed and entered service after the war.

Iowa class battleship
-- Complement: 2,700
-- Horsepower: 212,000

Alaska class battlecruiser
-- Complement: 1,517 or 1,799 or 2,251 (middle value same as the Des Moines)
-- Horsepower: 150,000

Des Moines class heavy cruiser
-- Complement: 1,799
-- Horsepower: 120,000

Baltimore class heavy cruiser
-- Complement: 1,146
-- Horsepower: 120,000

Worchester class light cruiser
-- Complement: 1,560
-- Horsepower: 125,000

Cleveland class light cruiser
-- Complement: 1,255
-- Horsepower: 100,000

 

[Kevin Renner]

Oh I'm sure he does. But just him thinking about the subject might cause his blood pressure to spike

 

[galveston bay]

the Des Moines had those very rapid fire 8 inch guns, which is hard to beat for shear volume of fire

for really heavy fire there are the Iowa class ships

The Guam is a half measure between the two

they would have made good post war command ships, but their crew size requirements made them too expensive for that role

 

[Delta Force]

Cost. Des Moines class would be cheaper to operate. Still, the Alaska class could have the crew cut down quite a lot if US Navy was prepared to only have one turret in operation, and only have partial AA available, though if the money was available they could be given Terrier SAMs.

the Des Moines had those very rapid fire 8 inch guns, which is hard to beat for shear volume of fire

for really heavy fire there are the Iowa class ships

The Guam is a half measure between the two

they would have made good post war command ships, but their crew size requirements made them too expensive for that role

Also, the Alaska class ships were commissioned or very close to completion by the end of World War II, while the Des Moines and Worchester class autoloading cruisers weren't commissioned until well after the War. The operational savings of the smaller cruisers would have to be weighed against the cost of completing them.

 

[CalBear]

Oh I'm sure he does. But just him thinking about the subject might cause his blood pressure to spike

I applied a cool compress, I hope to make it through the crisis.



The Alaska's, besides being the biggest construction error committed by the USN between the USS Vesuvius and the money pit known as the LCS (three lies in one acronym), were cursed with a number of remarkably bad design elements that effectively cursed them to failure.

1. Poor maneuverability. 808 feet long (80' LONGER than North Carolina class BB, 128' longer than a South Dakota BB and only 79' shorter than an Iowa class) 34,000 tons, ONE rudder (it is a good thing they operated in the Pacific, it is questionable if they could have completed a 360 degree turn in the Gulf of Mexico)

2. No proper flag quarters. As big as a battleship, and no flag quarters, meaning that if assigned to a SAG the force flag would have to be on a CA or CL.

3. Drew almost 32 feet of water at max (mean was 27'), this limited the ports it could use (Des Moines drew 22'). The USS Washington drew 34' 9".

4. Fuel hog compared to a CA. Six boilers instead of four.

5. Complement (wartime) was over 2,200. Des Moines class was 1,799 (wartime), North Carolina class complement was ~2,000 (wartime).

6. Throw weight. While the 12"/50 Mark 8 was a spectacular design, it was also the most expensive gun tube produced by the U.S. during WW II as $1.5M per tube. An Alaska could put out 21,150 pound of HE throw per minute. A Des Moines could put out 23,400 pound of HE per minute. For shore bombardment the 8"/55 RF was a better gun.

Ships were a white elephant.

 

[Grand Admiral Thrawn]

Does the Des Moines design have better TDS? That would be a big difference.

 

[TheMann]

The Alaska class were built with one job in mind, that being killing Japanese cruiser killers which never existed in the first place. They had no business ever existing in the first place.

 

[Delta Force]

Ships were a white elephant.

The Alaska class were built with one job in mind, that being killing Japanese cruiser killers which never existed in the first place. They had no business ever existing in the first place.

The PoD is after World War II.

 

[CalBear]

Then they are not even a white elephant. They are a waste of dock space. The CB's only possible use was as a carrier escort, but the CA/CL were better, especially as the 3"/50 RF came into service and replaced the far less effective 20mm & 40mm guns.

 

[kclcmdr]

The Alaska class were built with one job in mind, that being killing Japanese cruiser killers which never existed in the first place. They had no business ever existing in the first place.

The only IJN Battlecruisers left were those that were upgraded were the Kongo class but the Hiei and Kirishima fought and died at Guadalcanal while the Kongo & Haruna had engaged Taffy 3 among with Yamato & Nagoto.

Neither the Alaska nor the Guam were fully serviceable & combat ready until after Jan 45 so they both would have missed that battle off Samar Is.

If by some miracle or orders by the Naval board to have them commission faster in Mid 1944, they might have been ready for that Nov battle off Samar if the Admirals had thought to use them to escort the Taffys ...

But Two USN Battlecruisers plus their escorts and The Taffy's own escorts plus carriers against Four Imperial Japanese Battleships plus their escorts???

Probably the two USN BCs would have fought well or kept the concentration of fire upon them while the Taffy's escape or armed their remaining strikes with whatever bombloads and keep harassing that IJN TF until the two American Battlecruisers fought to the bitter end against the Four IJN BBs and maybe drove that Japanese Taskforce away from the invasion site like in OTL... maybe...

 

[CalBear]

The only IJN Battlecruisers left were those that were upgraded were the Kongo class but the Hiei and Kirishima fought and died at Guadalcanal while the Kongo & Haruna had engaged Taffy 3 among with Yamato & Nagoto.

Neither the Alaska nor the Guam were fully serviceable & combat ready until after Jan 45 so they both would have missed that battle off Samar Is.

If by some miracle or orders by the Naval board to have them commission faster in Mid 1944, they might have been ready for that Nov battle off Samar if the Admirals had thought to use them to escort the Taffys ...

But Two USN Battlecruisers plus their escorts and The Taffy's own escorts plus carriers against Four Imperial Japanese Battleships plus their escorts???

Probably the two USN BCs would have fought well or kept the concentration of fire upon them while the Taffy's escape or armed their remaining strikes with whatever bombloads and keep harassing that IJN TF until the two American Battlecruisers fought to the bitter end against the Four IJN BBs and maybe drove that Japanese Taskforce away from the invasion site like in OTL... maybe...

They wouldn't have been left with the Taffys. They would have been with the carriers on the run north. They were decent AAA platforms and could roll with the carriers even at top speed.

If the CB were there, it is possible that Halsey might have left BB divisions 8 & 9 (Washington, Alabama, South Dakota, and Massachusetts with Lee commanding) along with a DD squadron or two, but its unlikely.

 

[Delta Force]

I applied a cool compress, I hope to make it through the crisis.



The Alaska's, besides being the biggest construction error committed by the USN between the USS Vesuvius and the money pit known as the LCS (three lies in one acronym), were cursed with a number of remarkably bad design elements that effectively cursed them to failure.

1. Poor maneuverability. 808 feet long (80' LONGER than North Carolina class BB, 128' longer than a South Dakota BB and only 79' shorter than an Iowa class) 34,000 tons, ONE rudder (it is a good thing they operated in the Pacific, it is questionable if they could have completed a 360 degree turn in the Gulf of Mexico)

2. No proper flag quarters. As big as a battleship, and no flag quarters, meaning that if assigned to a SAG the force flag would have to be on a CA or CL.

3. Drew almost 32 feet of water at max (mean was 27'), this limited the ports it could use (Des Moines drew 22'). The USS Washington drew 34' 9".

4. Fuel hog compared to a CA. Six boilers instead of four.

5. Complement (wartime) was over 2,200. Des Moines class was 1,799 (wartime), North Carolina class complement was ~2,000 (wartime).

6. Throw weight. While the 12"/50 Mark 8 was a spectacular design, it was also the most expensive gun tube produced by the U.S. during WW II as $1.5M per tube. An Alaska could put out 21,150 pound of HE throw per minute. A Des Moines could put out 23,400 pound of HE per minute. For shore bombardment the 8"/55 RF was a better gun.

Ships were a white elephant.

1. I don't really know much about how rudders work on ships as opposed to boats. Is that something that can be retrofitted, or is it about as impractical as changing the shaft arrangement and/or propulsion type of a ship?

2. The Alaska class battlecruisers have a large area amidships for aircraft handling equipment that wasn't considered very useful in service. If the aircraft handling equipment is removed that would leave room for some upgrades to accommodations, anti-aircraft armament, etc.

3/4/5. You keep coming back to the South Dakota/North Carolina class battleships, but wouldn't they be very niche after World War II due to their inability to keep up with carrier groups or the cruisers being proposed/built by the Soviet Union? It seems they would be very large and expensive monitors.

6. If a Des Moines opened up like that it would deplete its magazine capacity in 15 minutes and wear out its barrels in about an hour and fifteen minutes. An Alaska would take an hour to an hour and 15 minutes just to deplete its magazine. Each shell packs a much larger wallop too, and the guns have a longer range.

 

[marathag]

Each shell packs a much larger wallop too, and the guns have a longer range.

12" Approximate Barrel Life 344 rounds
Bursting Charge HC Mark 17 - 79.44 lbs. Explosive D
Rate Of Fire 2.4 - 3.0 rounds per minute
Range@45 degrees 38,021 yards
15M of fire*79.44=2859.84 to 3574.8 Pounds of HE per tube

8" Approximate Barrel Life 780 rounds
Bursting Charge HC Mark 25 - 21.37 lbs. Explosive D
Rate Of Fire 10 rounds per minute
Range@41.0 degrees 29,800 yards

15M of fire*79.44=3205.5 Pounds of HE per tube

Now looks close in HE delivery.

 

[CalBear]

1. I don't really know much about how rudders work on ships as opposed to boats. Is that something that can be retrofitted, or is it about as impractical as changing the shaft arrangement and/or propulsion type of a ship?

2. The Alaska class battlecruisers have a large area amidships for aircraft handling equipment that wasn't considered very useful in service. If the aircraft handling equipment is removed that would leave room for some upgrades to accommodations, anti-aircraft armament, etc.

3/4/5. You keep coming back to the South Dakota/North Carolina class battleships, but wouldn't they be very niche after World War II due to their inability to keep up with carrier groups or the cruisers being proposed/built by the Soviet Union? It seems they would be very large and expensive monitors.

6. If a Des Moines opened up like that it would deplete its magazine capacity in 15 minutes and wear out its barrels in about an hour and fifteen minutes. An Alaska would take an hour to an hour and 15 minutes just to deplete its magazine. Each shell packs a much larger wallop too, and the guns have a longer range.

1. More or less impossible without rebuilding the entire stern of the ship.

2. AAA maybe, not for flag space. That needs to be near the bridge.

3/4/5. I keep coming back to them because they are simply vastly superior in almost every possible category. The CB are faster, but maneuver like a log raft at speed. The Alaska are porrly protected, have simply awful maneuverability, and have no real mission, never had any real mission, and would be hard pressed to find a mission that could not be done better by a battleship or equally well by a CA at a lower cost. The superb 12" gun was too late to be of any actual military utility.

6. True. However, if shell size matters then everything circles back to the two BB classes which can put out 50% more throw weight per minute. Even better it can now argued that it would be better to complete the last two Iowa class ships than proceed with the CB.

The ship class was more or less useless. Textbook example of institutional inertia overwhelming common sense and operational need.

 

[Not James Stockdale]

Does the Des Moines design have better TDS? That would be a big difference.

For all intents and purposes, the Alaskas didn't have a TDS. Their TDS was based on the Baltimores, so it would be comparable to any late Brooklyn descendants but pitiful compared to battleship or carrier TDS.

 

[Delta Force]

1. More or less impossible without rebuilding the entire stern of the ship.

Didn't the Essex class have only one rudder? I haven't been able to find any good pictures of it, but I found a picture of a scale model at a naval museum and it looks like there's only one rudder. Also, weren't the Midway class aircraft carriers unusually maneuverable and wet for aircraft carriers too?

2. AAA maybe, not for flag space. That needs to be near the bridge.

It can certainly fit flag space. There were proposals to convert USS Hawaii into an anti-aircraft command cruiser, including one that was actually budgeted and appropriated for in 1952. The question is really how much of a superstructure modification would be required.

3/4/5. I keep coming back to them because they are simply vastly superior in almost every possible category. The CB are faster, but maneuver like a log raft at speed. The Alaska are porrly protected, have simply awful maneuverability, and have no real mission, never had any real mission, and would be hard pressed to find a mission that could not be done better by a battleship or equally well by a CA at a lower cost. The superb 12" gun was too late to be of any actual military utility.

6. True. However, if shell size matters then everything circles back to the two BB classes which can put out 50% more throw weight per minute. Even better it can now argued that it would be better to complete the last two Iowa class ships than proceed with the CB.

It just seems there probably wouldn't have been much if any savings in completing new ships instead of using ones that were already finished or quite close to being finished. The Des Moines and Worchester class cruisers weren't even laid down by the time the first two Alaska class ships were already in commission, and the Hawaii launched a few months after that. Are there any good sources on how much these ships and other proposals would have cost, including completion of some of the incomplete ships?

The ship class was more or less useless. Textbook example of institutional inertia overwhelming common sense and operational need.

The Navy sure kept coming back to Hawaii and also Kentucky and Illinois with various conversion and completion plans.

 

[BlondieBC]

Does not CalBear have a opinion on this?

You only gave him an hour to respond. The Bear has to sleep.