Best British interwar fleet?

[Cryhavoc101]

I think your observations are spot on. Navies build ships to meet their specific needs. The RN has lots of water to cover, and the advantage of many bases, so they need, and can support lots of smaller ships. That's also how they can use guns with short barrel lives, they have many bases to replace them in. The USN for example needed to operate far from home bases, but this is something everyone here already knows. Let me make another point about the efficacy of building armored cruisers.

From pre WWI to WWII naval guns, and shells improved, and the range of combat greatly increased due to more advanced fire direction. It became harder, and harder to design a ship with enough armored protection to resist a similar caliber shell that they themselves carried. Greater range made this even harder because plunging fire made more deck armor necessary. That's why it was easier to design a reasonable armored CL on a 10,000 ton hull, then a CA. No one had prewar CA's that could resist 8" shells. The USN Baltimore Class, post treaty CA's were 4,000 tons over the preceding Treaty USS Wichita. An armored, or super cruiser with 9.2" guns would be nearly 20,000 tons. How many ships of that size would any interwar navy build?

Not even the Americans would build them, just where would they fit in their naval doctrine. The reason the USN built the "Large Cruiser" Alaska Class, (Over 30,000 tons,) was faulty intelligence, that the Japanese were building super cruisers. Interesting that U.S. Naval intelligence underestimated the size of the Yamato's. If they'd know they would've completed the last 2 Iowa's, and given the Montana's a higher priority. Really would have been a waste of resources, more Essex Class Carriers would've been more useful.

Along those lines what about a TL with no WNT where the USN converted all 6 Lexington's into carriers? That would be a real Black Shoe vs Brown Shoe battle. What would an international Carrier race look like? How many could the RN build, or convert? Would the RN take back the Fleet Air Arm? How would the Japanese respond. The French converted an old Battleship into a Carrier, in the late 30s loaded out with American Vindicator Dive Bombers, a plane that was unfairly maligned. It did good service as a land based DB, during the Battle of France. Everyone had large ships suitable for conversion, including Liners. During WWII Italy was converting 2 liners, but didn't finish them in time. This TL would certainly see an acceleration in the development of naval aviation. Any thoughts?

Totally - and we are talking - what 3 Deutschland class Armored Cruisers - which were no more armored than any heavy Cruiser - they were vulnerable to 6" shells (which mission killed the Graf Spree) and a single 8" shell hit effectively crippled the Graf Spree

So had the worlds navy's started spamming out CAs or lots of Heavy Cruisers then at extremis I can see the Towns being built as 8" gunned ships

As for the Carrier race - I always saw the carrier laid down in the 20s as experimental (granted they muddled through) - it was not until all of the learnings aligned with the Ark Royal that we saw the start of proper purpose built fleet carriers - with the ultimate expression being the Shōkaku-class and Essex class.

For Britain I could see them pretty much doing the same thing - make the RAF the 'owners' of air power during the 20s and 30s (the principle perceived threat to Britain was Bombers from continental Europe) but with increased carrier aviation the FAA would have a greater say in aircraft development and be more likely to achieve 'independence' earlier than OTL.

Carrier construction would be close to OTL I think with the Outrageous class being converted as well as Hermes Eagle and Argos - all pretty much grasping around learning the ropes of Naval Aviation.

But with more carriers in other navies (particularly if the US builds 6 Lexington CVs) I can see more and earlier purpose built CVs - an earlier 'lesser' Ark Royal

And with more follow on ships from that design into the 30s - with either an expansion into that type of ship or like OTL if the threat is deemed as a Littoral one then a move to Armored carriers

 

[Zheng He]

If there is no WNT, why does the US decide to convert all six Lexingtons into CVs instead of building them as BCs?

 

[Peg Leg Pom]

If there is no WNT, why does the US decide to convert all six Lexingtons into CVs instead of building them as BCs?

With no Washington Treaty does the US convert any of the deeply flawed Lexingtons to carriers at all?

 

[Colonel Grubb]

With no Washington Treaty does the US convert any of the deeply flawed Lexingtons to carriers at all?

If they keep all six hulls, I'd say they probably convert at least two to carriers with the rest as battle-cruisers, but with iterative changes worked in during construction as it becomes apparent how flawed they are compared to what the British have/are outputting. Depending on the RN and IJN are doing, I'd bet the USN still wanted to figure out if the large carrier concept actually works for the scouting force - keeping up with the joneses in experimenting with carrier aviation and doctrines.

 

[WaterproofPotatoes]

So, if everyone in the Big 3 gets their wish list of ships commissioned in 1920 or later, adjusted for realism, (no 18" ships, Japan doesn't get to spend 1.5x her GDP and 270% of her annual steel production on the IJN) that adds up to:

Royal Navy:

1× Hood

4× G3 class battlecruisers

3× Courageous class fleet carrier

1× light carrier (Hermes)

Imperial Japanese Navy:

2× Nagato class battleship

2× Tosa class battleship

4× Amagi class battlecruiser or 2× Atago class fleet carrier conversions in lieu of 2× gun battlecruisers

United States Navy:

4× Colorado class battleships

6× South Dakota class battleships

6× Lexington class battlecruisers.

Given the above figures, I'd argue for 3x Lexington class carrier conversions, as that would give 3:2 numerical superiority over Japan in terms of fleet carriers, and quantitative parity, qualitative superiority over Britain's 3 carriers. Japan is the more important target, as Britain and the USA are not at all likely to enter naval conflict.

 

[Peg Leg Pom]

So, if everyone in the Big 3 gets their wish list of ships commissioned in 1920 or later, adjusted for realism, (no 18" ships, Japan doesn't get to spend 1.5x her GDP and 270% of her annual steel production on the IJN) that adds up to:

Royal Navy:

1× Hood

4× G3 class battlecruisers

3× Courageous class fleet carrier

1× light carrier (Hermes)

I think that with no WNT and an unofficial ban on 18" guns the four planned N3 battleships are eventually replaced by at least 2 improved G3's.

 

[Jellico]

With no Washington Treaty does the US convert any of the deeply flawed Lexingtons to carriers at all?

OTL they were starting to figure out the Lexingtons were flawed to the point of dangerousness. SO aircraft carrier was one of the ideas floated to do something with these big potentially useless hulls. On these threads you usually see guesses ranging from all, some, or none getting converted.

As for the Carrier race - I always saw the carrier laid down in the 20s as experimental (granted they muddled through) - it was not until all of the learnings aligned with the Ark Royal that we saw the start of proper purpose built fleet carriers - with the ultimate expression being the Shōkaku-class and Essex class.

For Britain I could see them pretty much doing the same thing - make the RAF the 'owners' of air power during the 20s and 30s (the principle perceived threat to Britain was Bombers from continental Europe) but with increased carrier aviation the FAA would have a greater say in aircraft development and be more likely to achieve 'independence' earlier than OTL.

Carrier construction would be close to OTL I think with the Outrageous class being converted as well as Hermes Eagle and Argos - all pretty much grasping around learning the ropes of Naval Aviation.

But with more carriers in other navies (particularly if the US builds 6 Lexington CVs) I can see more and earlier purpose built CVs - an earlier 'lesser' Ark Royal

And with more follow on ships from that design into the 30s - with either an expansion into that type of ship or like OTL if the threat is deemed as a Littoral one then a move to Armored carriers

Got to second this. OTL no one was building up to their Treaty carrier limits till they got the bugs worked out and were preparing for war.

Probably the big change would be you could build small carriers because they aren't coming out of your tonnage allotment. When you have a hard limit you have to only build fleet carriers. Who wants small carriers is a different story.

 

[Peg Leg Pom]

Probably the big change would be you could build small carriers because they aren't coming out of your tonnage allotment. When you have a hard limit you have to only build fleet carriers. Who wants small carriers is a different story.

The RN wanted small trade protection carriers from the start to back up the light cruisers.

 

[Jellico]

But you have to pay for them. Aircraft are a continuous wasting expense. And experiments with ships like HMS Vindictive showed hard limit on how small you could go. Just because you want to doesn't mean that you can. Really these mid sized carriers are the super cruiser replacement in the 30s, if only for command and search facilities for light cruiser squadrons. Getting there is the challenge.

 

[Belisarius II]

Totally - and we are talking - what 3 Deutschland class Armored Cruisers - which were no more armored than any heavy Cruiser - they were vulnerable to 6" shells (which mission killed the Graf Spree) and a single 8" shell hit effectively crippled the Graf Spree

So had the worlds navy's started spamming out CAs or lots of Heavy Cruisers then at extremis I can see the Towns being built as 8" gunned ships

As for the Carrier race - I always saw the carrier laid down in the 20s as experimental (granted they muddled through) - it was not until all of the learnings aligned with the Ark Royal that we saw the start of proper purpose built fleet carriers - with the ultimate expression being the Shōkaku-class and Essex class.

For Britain I could see them pretty much doing the same thing - make the RAF the 'owners' of air power during the 20s and 30s (the principle perceived threat to Britain was Bombers from continental Europe) but with increased carrier aviation the FAA would have a greater say in aircraft development and be more likely to achieve 'independence' earlier than OTL.

Carrier construction would be close to OTL I think with the Outrageous class being converted as well as Hermes Eagle and Argos - all pretty much grasping around learning the ropes of Naval Aviation.

But with more carriers in other navies (particularly if the US builds 6 Lexington CVs) I can see more and earlier purpose built CVs - an earlier 'lesser' Ark Royal

And with more follow on ships from that design into the 30s - with either an expansion into that type of ship or like OTL if the threat is deemed as a Littoral one then a move to Armored carriers

Your spot on about the Deutschland's, they were an unbalanced design, that were later re designated has heavy cruisers. Graf Spree was lucky she only ran into 3 small treaty cruisers. If it was 2 Town's, and a County I don't think she'd have made it to Montevideo. Your right Lexington, and Saratoga were experiments, serving has the nursery school of American Naval Aviation, so a TL where we'd convert all 6 is very improbable. Ark Royal was a great carrier, but for the fault of one engine room, that when flooded would sink the ship. She had a large air group, and wooden flight deck like USN Carriers. Later Invincibles, steel decks, small groups, different choices, still hotly debated.

 

[SsgtC]

Later Invincibles, steel decks, small groups, different choices, still hotly debated.

A factor I think of being designed for the war the Royal Navy thought they were going to fight verses the war they actually fought. American carriers were focused on the Pacific almost from the start leading to their decision to go with larger air groups and things like wooden flight deck to maximize hanger height and permanent deck parks. Had the UK been focused on fighting a naval war in the Pacific, we might have seen them make very different design choices

 

[Peg Leg Pom]

A factor I think of being designed for the war the Royal Navy thought they were going to fight verses the war they actually fought.

The RN did end up fighting the Mediterranean War they planned the Illustrious class for.

 

[Belisarius II]

But you have to pay for them. Aircraft are a continuous wasting expense. And experiments with ships like HMS Vindictive showed hard limit on how small you could go. Just because you want to doesn't mean that you can. Really these mid sized carriers are the super cruiser replacement in the 30s, if only for command and search facilities for light cruiser squadrons. Getting there is the challenge.

I take your points, but don't quite agree. Small carriers could be built on large merchant, or CLs hulls like the CVEs, and CVLs of WWII. 10,000 ton hulls, with no armor, or heavy guns. Your right aircraft are a wasting expense, with short service lives, and high accident rates for aircraft, & crews. Aircraft are the ammunition of a carrier, and in the 1920s cost only a few thousand dollars, with no shortage of volunteer risk takers eager to fly them. What was the cost of the ammo expended in a gunnery exercise? The hull is the cheapest element of a ship. Armor plate, big guns, and turrets were the biggest cost factor in surface ships, today it's electronics.

Based on interwar conversions, and WWII building programs you could build a 10,000 light carrier, for a lot less then a 20,000 ton armored cruiser. Even in the 20s a carrier is generally a more versatile ship. Though I do concede it's a debatable point, considering the immaturity of naval aircraft of the time. Hindsight is 20/20, it depends on how visionary Congress, Parliament, the Diet, and the Admiralties were, or could plausibly be for an OTL.

 

[WaterproofPotatoes]

I think that with no WNT and an unofficial ban on 18" guns the four planned N3 battleships are eventually replaced by at least 2 improved G3's.

Would you wager a G3a with the aft turret relocated to behind the funnel uptakes, given the likely blast issues caused by the midships turret?

 

[Peg Leg Pom]

Would you wager a G3a with the aft turret relocated to behind the funnel uptakes, given the likely blast issues caused by the midships turret?

Something like that.

 

[Jellico]

I take your points, but don't quite agree. Small carriers could be built on large merchant, or CLs hulls like the CVEs, and CVLs of WWII. 10,000 ton hulls, with no armor, or heavy guns. Your right aircraft are a wasting expense, with short service lives, and high accident rates for aircraft, & crews. Aircraft are the ammunition of a carrier, and in the 1920s cost only a few thousand dollars, with no shortage of volunteer risk takers eager to fly them. What was the cost of the ammo expended in a gunnery exercise? The hull is the cheapest element of a ship. Armor plate, big guns, and turrets were the biggest cost factor in surface ships, today it's electronics.

Based on interwar conversions, and WWII building programs you could build a 10,000 light carrier, for a lot less then a 20,000 ton armored cruiser. Even in the 20s a carrier is generally a more versatile ship. Though I do concede it's a debatable point, considering the immaturity of naval aircraft of the time. Hindsight is 20/20, it depends on how visionary Congress, Parliament, the Diet, and the Admiralties were, or could plausibly be for an OTL.

I must admit when I went to Wikipedia a minute ago to confirm ship weights I didn't expect to find
https://en.wikipedia.org/wiki/Light_aircraft_carrier
"converted from Cleveland-class light cruisers, were unsatisfactory ships for aviation with their narrow, short decks and slender, high-sheer hulls; in virtually all respects the escort carriers were superior aviation vessels. "

I think that matches up with the HMS Vindictive experience. If you want fleet type speeds you need 15,000 tons as per the Saipans and Light Fleets. HMS Hermes is very interesting here because it is of the period we are talking about.

It was posted here a few months back that cruisers are cheaper to run than small aircraft carriers. That is your competition out on the distant sea lanes and they are probably hard to match. That is why I agree the comparison should be against an armored cruiser which is more expensive. I think in the 20s there is still too much learning going on replace the armored cruiser just yet. See Hermes again. But there would be an evolutionary process and by the 30s it is practical within limits.

Would you wager a G3a with the aft turret relocated to behind the funnel uptakes, given the likely blast issues caused by the midships turret?

This one always seems like a no brainer because that was the planning otl. But I can't help but wonder if that is the effects of the Treaties talking. The 16" limit limited armor as well as guns and freed up tonnage for engines and moving turrets. Would that happen without the 16" limit? There were other factors like underwater damage and AA arcs at play as well. But that is where it gets interesting.

 

[Peg Leg Pom]

I must admit when I went to Wikipedia a minute ago to confirm ship weights I didn't expect to find
https://en.wikipedia.org/wiki/Light_aircraft_carrier
"converted from Cleveland-class light cruisers, were unsatisfactory ships for aviation with their narrow, short decks and slender, high-sheer hulls; in virtually all respects the escort carriers were superior aviation vessels. "

I think that matches up with the HMS Vindictive experience. If you want fleet type speeds you need 15,000 tons as per the Saipans and Light Fleets. HMS Hermes is very interesting here because it is of the period we are talking about.

It was posted here a few months back that cruisers are cheaper to run than small aircraft carriers. That is your competition out on the distant sea lanes and they are probably hard to match. That is why I agree the comparison should be against an armored cruiser which is more expensive. I think in the 20s there is still too much learning going on replace the armored cruiser just yet. See Hermes again. But there would be an evolutionary process and by the 30s it is practical within limits.

I think a trade protection carrier if purpose built rather than converted would have been along the lines of a slightly larger Hermes.

 

[Belisarius II]

If there is no WNT, why does the US decide to convert all six Lexingtons into CVs instead of building them as BCs?

I don't really think it was likely. I only thought they were pretty good carriers, and in retrospect they would have been more useful has carriers, then Battlecruisers. By 1941 Japan had a big advantage over the USN, and RN in naval air power. The USN could really have used 4 more big carriers after Pearl Harbor. Everyone was experimenting in the interwar period. The Americans made the Ranger too small, and the Wasp should have been another Yorktown Class. The Essex was based on the lessons learned with the Yorktown's. One step at a time. The Lexington's were the biggest, and fastest carriers in the interwar period, with the largest air groups. Tough ships, just not very maneuverable.

 

[Dorknought]

Based on interwar conversions, and WWII building programs you could build a 10,000 light carrier, for a lot less then a 20,000 ton armored cruiser. Even in the 20s a carrier is generally a more versatile ship. Though I do concede it's a debatable point, considering the immaturity of naval aircraft of the time. Hindsight is 20/20, it depends on how visionary Congress, Parliament, the Diet, and the Admiralties were, or could plausibly be for an OTL.

Navies were starting to become sensitive to maintenance costs and the costs of different types of warships. The graph below shows 1920-30's RN figures for total warship cost of ownership or the cost of the capability over a 26 year period with costs of construction and maintenance per ton. This factors in the annual maintenance, crew pay, consumable stores like food, ammo and fuel, regular refits and a 'large repair'. It excludes pensions and depreciation.

As you can see, the costs of a 'submarine' capability or 'destroyers' was significantly higher than 'battleships'. Carriers had an airwing that was replaced every 5 or so years. BC were slightly more expensive to run as they burned more fuel at higher speeds. Carriers also ran at speed to conduct air operations. Destroyers and Submarines were more expensive because they only had 16 and 13 year lives respectively so over the 26 year lifespan of a battleship, they are replaced twice.

Below the graph is a nominal exchange for an 8 Ship Battle Squadron, ie 8 BB vs 7BC vs 3CV vs 6CVL etc. In the 20’s carriers were expensive untried auxiliaries.

 

[WaterproofPotatoes]

This one always seems like a no brainer because that was the planning otl. But I can't help but wonder if that is the effects of the Treaties talking. The 16" limit limited armor as well as guns and freed up tonnage for engines and moving turrets. Would that happen without the 16" limit? There were other factors like underwater damage and AA arcs at play as well. But that is where it gets interesting.

18" guns in the early 20s are something of a Pandora's Box- once it's opened, it can't be closed, but opening it leaves everyone worse off. An 18" armed ship needs to be utterly massive. The difference between the weight of shells fired by the British 15" and contemporary 16" guns wasn't all that much- the BL Mk. I 15" shell weight was only a couple hundred pounds less than the American 16" Mk. 1 and 2 and Japanese 41cm 3rd Year Type- 1920 lbs vs 2110 and 2200 respectively. The difference between those and the proposed 18" guns was massive. The USN's would have fired a 2900 lb shell, the Japanese 46cm/L50 a 3000 lb shell, and the British 18"s a 3320 lb shell (the new 18 for the N3s would have fired a 2980lb shell at higher velocity)- and the Americans proposed a superheavy 3850 lb AP shell and the Brits a 4000 lb HE shell.

The only country that can really afford to start building 18" behemoths is the USA, and during testing, they found their 18" gun to be a great disappointment- excessive barrel wear, slow rate of fire and penetration not a significant improvement over the 16" Mk. 2.

It would be interesting to see what the USN would do with Tillman's Maximum Battleship designs as well. I don't think the 6-gun turrets would be realistic, but a faster ship with 16" triples would be quite doable.