A 23 000 tons Yorktown class

[Anderman]

Inspired by the thread of a Illustrious with 4000 extra tons

https://www.alternatehistory.com/forum/threads/ahc-27000-tonne-illustrious-class-carrier.450854/

what would you do with 3000 extra tons for the Yorktown class with was in otl at 19 800 tons.
Could a ship with otl dimension of a Yorktwon build with an amoured flight deck or even a amoured box hangar without losing to much aircraft capacity?

 

[McPherson]

Inspired by the thread of a Illustrious with 4000 extra tons

https://www.alternatehistory.com/forum/threads/ahc-27000-tonne-illustrious-class-carrier.450854/

what would you do with 3000 extra tons for the Yorktown class with was in otl at 19 800 tons.
Could a ship with otl dimension of a Yorktwon build with an amoured flight deck or even a amoured box hangar without losing to much aircraft capacity?

More fuel, beamier longer hull, deck edge lifts. Give me the 1930s known to the USN attributes that make her a better match for the Shokakus. 3,000 tonnes might not be enough. 5,000 tonnes and now we're talking...

 

[NOMISYRRUC]

Inspired by the thread of a Illustrious with 4000 extra tons

https://www.alternatehistory.com/forum/threads/ahc-27000-tonne-illustrious-class-carrier.450854/

what would you do with 3000 extra tons for the Yorktown class with was in otl at 19 800 tons.
Could a ship with otl dimension of a Yorktwon build with an amoured flight deck or even a amoured box hangar without losing to much aircraft capacity?

Is the POD the USN deciding to use the remaining 69,000 tons of its WNT allowance to build three 23,000 ton ships instead of five 13,800 ton ships?

 

[SsgtC]

Inspired by the thread of a Illustrious with 4000 extra tons

https://www.alternatehistory.com/forum/threads/ahc-27000-tonne-illustrious-class-carrier.450854/

what would you do with 3000 extra tons for the Yorktown class with was in otl at 19 800 tons.
Could a ship with otl dimension of a Yorktwon build with an amoured flight deck or even a amoured box hangar without losing to much aircraft capacity?

No. The size of the structural members required to support an armored flight deck would severely curtail the height of the hanger. And the USN preferred open hanger decks over closed in. That let them warm up aircraft engines in the hanger instead of on the flight deck. There were other operational decisions relating to their designs as well that mitigate against enclosing the hanger or armoring the flight deck.

What you're more likely to see with an extra 3,000 tons to play with, is a more robust torpedo defense system and additional fuel and AvGas storage.

 

[McPherson]

Is the POD the USN deciding to use the remaining 69,000 tons of its WNT allowance to build three 23,000 ton ships instead of five 13,800 ton ships?

Hmm. Three Yorktowns. Still leaves the USN short of the five she needs. How about a couple of fast 22,500 ton AOs or subsidized ocean liners (to go into that 1937 United States Maritime Commission bill?).

 

[marathag]

Inspired by the thread of a Illustrious with 4000 extra tons

https://www.alternatehistory.com/forum/threads/ahc-27000-tonne-illustrious-class-carrier.450854/

what would you do with 3000 extra tons for the Yorktown class with was in otl at 19 800 tons.
Could a ship with otl dimension of a Yorktwon build with an amoured flight deck or even a amoured box hangar without losing to much aircraft capacity?

Likely would be slightly larger with similar armor layout, but better anti-Torpedo defense, per the blisters added to Enterprise during the war.

Also possible she would have gotten 6"L/47 guns in dual gunhouses, with possibility of them being set to be Dual Purpose, as happened midway thru the War

 

[Zheng He]

No. The size of the structural members required to support an armored flight deck would severely curtail the height of the hanger. And the USN preferred open hanger decks over closed in. That let them warm up aircraft engines in the hanger instead of on the flight deck. There were other operational decisions relating to their designs as well that mitigate against enclosing the hanger or armoring the flight deck.

What you're more likely to see with an extra 3,000 tons to play with, is a more robust torpedo defense system and additional fuel and AvGas storage.

Probably a lot of what ENTERPRISE got in 1943.

 

[Ian Henderson]

It’s been a while since I’ve read the relevant volume of Friedman, but IIRC there was a design that was a Yorktown but with a unit machinery layout. That seems a very likely improvement.

 

[SsgtC]

It’s been a while since I’ve read the relevant volume of Friedman, but IIRC there was a design that was a Yorktown but with a unit machinery layout. That seems a very likely improvement.

That sounds like the early design study for what would become the Essex class. IIRC, wasn't the original design proposal an enlarged Yorktown?

 

[McPherson]

That sounds like the early design study for what would become the Essex class. IIRC, wasn't the original design proposal an enlarged Yorktown?

Yup, with a few Wasp features thrown in.

 

[1Big Rich]

Inspired by the thread of a Illustrious with 4000 extra tons

https://www.alternatehistory.com/forum/threads/ahc-27000-tonne-illustrious-class-carrier.450854/

what would you do with 3000 extra tons for the Yorktown class with was in otl at 19 800 tons.
Could a ship with otl dimension of a Yorktwon build with an amoured flight deck or even a amoured box hangar without losing to much aircraft capacity?

The knock on the Yorktowns was they had nine boilers in three adjacent boiler rooms. This made it easier to knock out their power as opposed to a carrier with unit machinery (like the Essex class). The USN really wanted to move on from the design after the first two, but the design for Essex wasn't ready, so CV-8 was ordered as a repeat, slightly modified Yorktown.
With an extra three thousand tons, we should be able to get them with unit machinery, as well as a wider flight deck like Hornet CV-8 had. (The reason she was chosen for the Doolittle Raid, she had the widest flight deck then in service. As well as being in the right place at the right time!)

I think an armored flight deck would have to come at expense of the airgroup, which is a non-starter for the USN based on their experiences in the pre-war Fleet Problems. In addition, making the flight deck the strength deck means being very careful about elevator size, as they are holes in the strength deck. The USN philosophy was the floor of the hangar was the strength deck, and the flight deck was a superstructure built on top of it.

An aside on armored flight decks: If we want to talk about carriers with fully armored flight decks, the conversation starts with the Audacious class carriers. The previous carriers so described, whether RN or the USN's Midway, had only partially armored flight decks, mostly over the vitals amidships.

To return to the extra tonnage on a Yorktown, we might not get much more aircraft capacity, but they had a good, effective airgroup to begin with.

Regards,

 

[McPherson]

The knock on the Yorktowns was they had nine boilers in three adjacent boiler rooms. This made it easier to knock out their power as opposed to a carrier with unit machinery (like the Essex class). The USN really wanted to move on from the design after the first two, but the design for Essex wasn't ready, so CV-8 was ordered as a repeat, slightly modified Yorktown.

The problem with unit machinery is that trunking the air circuit (intake and exhaust) means the air conduits have to eat even more internal volume of the pass throughs up intruding into the hanger. This side shanking produces a longer pinch for the aircraft travel through fore to aft as the strike below operations are conducted. So there is a negative trade-off and a severe one until the US shipwrights learn how to outboard the stacks from below the hanger deck. This happens with the Essex class.

With an extra three thousand tons, we should be able to get them with unit machinery, as well as a wider flight deck like Hornet CV-8 had. (The reason she was chosen for the Doolittle Raid, she had the widest flight deck then in service. As well as being in the right place at the right time!).

This awaits a re-spotting of the gun tubs, some of the work catwalks and alleyways and so forth. Not so noticeable in the macro, but the flight deck overhang had to be tweaked to make it possible on Hornet.

I think an armored flight deck would have to come at expense of the airgroup, which is a non-starter for the USN based on their experiences in the pre-war Fleet Problems. In addition, making the flight deck the strength deck means being very careful about elevator size, as they are holes in the strength deck. The USN philosophy was the floor of the hangar was the strength deck, and the flight deck was a superstructure built on top of it.

Top-weight. British carriers tended to turn keel to the sky and go down fast taking their crews with them. Add the shock problem, where that armored structure acted like a giant bell and sent shock throughout the hull when a bomb exploded against it. British hulls bent and warped from the forces transmitted to the hull plating and frames. This affected everything that was a moving subsystem in a British carrier from elevator up down travel to power take offs balancing, to shaft alley supports, to the screws themselves. Two good prangings from 1,000 lbers and a British carrier could lose up to 25% of her speed... permanently. And SPEED is the lifeblood of launch and trap operations for an aircraft carrier. Wind over deck has to be 20 knots; even with catapults for a WW II Allied carrier.

An aside on armored flight decks: If we want to talk about carriers with fully armored flight decks, the conversation starts with the Audacious class carriers. The previous carriers so described, whether RN or the USN's Midway, had only partially armored flight decks, mostly over the vitals amidships.

First true armored Americans are the Forrestals, I believe.

To return to the extra tonnage on a Yorktown, we might not get much more aircraft capacity, but they had a good, effective airgroup to begin with.

Regards,

Extra torpedo defense and more fuel. Once past 80 or so aircraft, there are stowage and plane handling problems that interfere with effective op-tempos on a flattop.

 

[NOMISYRRUC]

Inspired by the thread of a Illustrious with 4000 extra tons

https://www.alternatehistory.com/forum/threads/ahc-27000-tonne-illustrious-class-carrier.450854/

what would you do with 3000 extra tons for the Yorktown class with was in otl at 19 800 tons.
Could a ship with otl dimension of a Yorktwon build with an amoured flight deck or even a amoured box hangar without losing to much aircraft capacity?

If you built Yorktown and Enterprise to a 23,000 ton design the Americans won't be able to build Ranger without breaking the Washington Naval Treaty. See ATL 1 in the table below.

Displacements are from Chesneau.

If the USN was going to do this they would have built three 23,000 ton ships instead of the OTL Ranger, Yorktown and Enterprise. See ALT 2 above. IIRC from Friedman this was actually considered, but they decided on five 13,800 ton ships because they wanted the maximum number of hulls. However, Ranger proved to be unsatisfactory and the plan was changed to two 20,000 ton ships (which became Yorktown and Enterprise) and two 14,000 ton ships (Ranger and Wasp).

 

[SsgtC]

If the USN was going to do this they would have built three 23,000 ton ships instead of the OTL Ranger, Yorktown and Enterprise. See ALT 2 above. IIRC from Friedman this was actually considered, but they decided on five 13,800 ton ships because they wanted the maximum number of hulls. However, Ranger proved to be unsatisfactory and the plan was changed to two 20,000 ton ships (which became Yorktown and Enterprise) and two 14,000 ton ships (Ranger and Wasp).

Yeah, the Navy realised just how badly compromised Ranger was because of their drive to minimize everything as much as possible. Wasp was built because of the sheer amount of tonnage left. And even then, she was built to a modified Yorktown design (biggest change, no torpedo defense system). The 30s were a weird time for ship design and construction

 

[Anderman]

If you built Yorktown and Enterprise to a 23,000 ton design the Americans won't be able to build Ranger without breaking the Washington Naval Treaty. See ATL 1 in the table below.

View attachment 412364

Displacements are from Chesneau.

If the USN was going to do this they would have built three 23,000 ton ships instead of the OTL Ranger, Yorktown and Enterprise. See ALT 2 above. IIRC from Friedman this was actually considered, but they decided on five 13,800 ton ships because they wanted the maximum number of hulls. However, Ranger proved to be unsatisfactory and the plan was changed to two 20,000 ton ships (which became Yorktown and Enterprise) and two 14,000 ton ships (Ranger and Wasp).

I am aware of the tonnage limitation. I am more interested in the technical limitation by adding 3000 tons who will the air group affected etc..

 

[SsgtC]

I am aware of the tonnage limitation. I am more interested in the technical limitation by adding 3000 tons who will the air group affected etc..

More AvGas storage almost certainly. Maybe more weapons storage. Maybe a deck edge lift. Probably a little wider flight deck.

 

[NOMISYRRUC]

I am aware of the tonnage limitation. I am more interested in the technical limitation by adding 3000 tons who will the air group affected etc..

Fair enough. However, I think it might have worked out better for the Americans if they had built three 23,000 ton ships instead of the OTL Ranger, Yorktown, Enterprise and Wasp.

 

[McPherson]

Fair enough. However, I think it might have worked out better for the Americans if they had built three 23,000 ton ships instead of the OTL Ranger, Yorktown, Enterprise and Wasp.

Who is going to run some of those Pedestals to Malta? Wasp won't be there for her part. Butterflies flapping...

 

[Zheng He]

Yeah, the Navy realised just how badly compromised Ranger was because of their drive to minimize everything as much as possible. Wasp was built because of the sheer amount of tonnage left. And even then, she was built to a modified Yorktown design (biggest change, no torpedo defense system). The 30s were a weird time for ship design and construction

Of course they were, carriers were new and experimentation was a constant. It's easy to criticize the Ranger design with 20/20 hindsight but at the time when all we had was the tiny little Langley and the two behemoths, it is understandable that somebody thought maybe we should try going the other way and build something that is cheaper and easier to mass produce (in as much as you can mass produce any warship).

 

[Cryhavoc101]

Inspired by the thread of a Illustrious with 4000 extra tons

https://www.alternatehistory.com/forum/threads/ahc-27000-tonne-illustrious-class-carrier.450854/

what would you do with 3000 extra tons for the Yorktown class with was in otl at 19 800 tons.
Could a ship with otl dimension of a Yorktwon build with an amoured flight deck or even a amoured box hangar without losing to much aircraft capacity?

Improved torpedo protection and increased storage of Avgas, weapons and spares - I would only go the armoured route if they were primarily intended to operate in Littoral environments such as the North Sea and the central Med within range of twin and triple engined land bombers which is unlikely for the US designers in the early 30s.

Top-weight. British carriers tended to turn keel to the sky and go down fast taking their crews with them. Add the shock problem, where that armored structure acted like a giant bell and sent shock throughout the hull when a bomb exploded against it. British hulls bent and warped from the forces transmitted to the hull plating and frames. This affected everything that was a moving subsystem in a British carrier from elevator up down travel to power take offs balancing, to shaft alley supports, to the screws themselves. Two good prangings from 1,000 lbers and a British carrier could lose up to 25% of her speed... permanently. And SPEED is the lifeblood of launch and trap operations for an aircraft carrier. Wind over deck has to be 20 knots; even with catapults for a WW II Allied carrier..

Aside from Courageous and Eagle which were WW1 conversions and not armoured box type carriers and did not have an armoured deck I cannot think of any other British fleet carrier that capsized quickly. And in both examples they were torpedoed by Submarine.

Certainly none of the 6 Armoured carriers or Unicorn (who had a 2" deck) were sunk - the only other armoured deck was the IJN Taiho took 2 hours to sink 'stern first' after the first fuel vapour explosion ultimately due to poor design and poor damage control.

Illustrious was bombed to hell in 41 and was still in commission at the end of the war.

She did have problems later in her life from one of her shafts but that was partially due to a lack of funding in post war Britain for the necessary repair work as much as it was war damage and hard war use but was still used until 55

Damage to her machinary at the time was almost certainly caused by multilple near misses from subsequant attacks while under repair in the shallow waters of Valetta Harbour and not a result of 'Giant Bell' shock effects from hits to her Armoured deck.

And any other ww2 carrier in 1941 suffering that level of damage would already have been a new reef from 10th Jan 41

And I cannot think of an example during the war were a carrier was hit by multiple 1000 pounders and remained operational

Extra torpedo defense and more fuel. Once past 80 or so aircraft, there are stowage and plane handling problems that interfere with effective op-tempos on a flattop.

Yep. Once you have folding F4F-4s and practical post Coral sea and Midway experiance the hanger sizes on the Yorktowns are probably big enough.

We did a thread a few years back that asked the question around the Wasp being a '3'rd fully leaded Yorktown rather than a Yorktown 'lite' and Essex Ordered as a 5th Yorktown to be built at the same time as Hornet (laid down in late 1939 rather than April 41)

I think much could have been done with 3 Yorktowns in 41 and 5 in mid 42!