Fate of Alaska class if finished as carriers?

[Lascaris]

So the discussion has come up on a different thread in alternatehistory.com. Say that because reasons the Alaska conversion to carriers went ahead in late 1941. Come the end of the war in 1945 you have two carriers, that overall are worse than the Essex, not standardized and possibly unneeded... if you are the USN and have two plus dozen Essex in addition to other ships. For everyone else they are 30,000t ships that can carry a larger air group than anything non-American still afloat.

Soo how do you dispose of them? Leave them to rust in reserve? Convert them to something else like prototype LPH? Make them command ships like the Saipans? Hand them over/sell them to allies for example France or Australia or perhaps even Britain?

 

[Moose]

Decent chance an ally would bite if they were made available quickly, they'd have been a pretty good fit for the Dutch. Conversion doesn't make a ton of sense because they'd cost more to convert than the Saipan class while not being inherently better in those roles. Honestly though the odds are they just go into reserve and stay there until the Navy gets around to scrapping them.

 

[Siberia]

Decent chance an ally would bite if they were made available quickly, they'd have been a pretty good fit for the Dutch.

How large is the crew that will be needed to man them though? HNLMS Karel Doorman, a Colossus-class light fleet carrier, had a complement of around 1,300. I have to wonder if the increased manpower and running costs would be considered bearable for the increase in capability.

 

[Dilandu]

Scrapped soon after war likely; non-standard design, less efficient than Essex.

 

[EwenS]

Scrapped soon after war likely; non-standard design, less efficient than Essex.

Probably just laid up like all the other surplus vessels, including many Essex class, until the decision is made to scrap them in the late 1950s

How large is the crew that will be needed to man them though? HNLMS Karel Doorman, a Colossus-class light fleet carrier, had a complement of around 1,300. I have to wonder if the increased manpower and running costs would be considered bearable for the increase in capability.

Remember the Dutch started in WW2 with two MACs (Gadila & Macoma) before moving to Karel Doorman (ex HMS Nairana, a British built escort carrier) in 1946, before moving to Karel Doorman (ex HMS Venerable of the Colossus class) in 1948.

Canada cut its intended carrier fleet from 2 Colossus / Majestic to just one ship post WW2.

Australia wouldn't have wanted anything bigger than a Colossus in that period since it was just getting its FAA built.

Soo how do you dispose of them? Leave them to rust in reserve? Convert them to something else like prototype LPH? Make them command ships like the Saipans? Hand them over/sell them to allies for example France or Australia or perhaps even Britain?

USN thinking about the LPH began with CVE conversions of a Casablanca (Thetis Bay) before looking at a Commencement Bay (Block Island - conversion cancelled) before ordering purpose built Iwo Jima class and filling the gap with redundant Essex class. They certainly didn't need the speed of a fleet carrier with half the Essex powerplant mothballed.

Britain had more carriers build or building than it knew what to do with. It preferred Colossus class as front line carriers post-war due to manning problems. Added to which Britain didn't have the dollars to afford a purchase.

 

[Archibald]

From memory, the Alaskas single rudder had them turning as fast as a 500 000 ton supertanker. No idea if that's a nuisance for an aircraft carrier, against a battlecruiser ?

The Saipans were never sold to foreign navies, only the much smaller Independance class (2 for France, 1 for Spain: Bois Belleau, Lafayette and Dedalo. After dumping ours in 1962, we ingrate french nicknamed the spanish ship Pedalo : paddle boat, when our southern neighborgh used it from 1967 to 1989 with Harriers on deck).

 

[Scott Kenny]

I think they'd get mothballed, then scrapped in the 50s.

 

[DWG]

The UK wouldn't want them, we had more carriers than we knew what to do with. The Dutch and Commonwealth Navies are all RN-adjacent, so a US ship isn't an immediately obvious choice if the RN's going to be handing out CVLs. France is really the only possibility, and would the USN be willing given it always seemed to cut France a bit too close to the bone during WWII (cf Richelieu completing her US refit with a gunnery radar set suitable for a PT boat)?

 

[Christopher Wang]

Maybe the Alaska class carrier conversions could be used post-WWII as Harrier carriers. According to the preliminary design schematics, the Alaska class carrier conversions were projected to have a pair of 48-ft by 44-ft elevators. That should be enough space for the AV-8B Harrier II which has a length of 46-ft 4-in and a wingspan of 30-ft 4-in.

 

[Dilandu]

Maybe the Alaska class carrier conversions could be used post-WWII as Harrier carriers. According to the preliminary design schematics, the Alaska class carrier conversions were projected to have a pair of 48-ft by 44-ft elevators. That should be enough space for the AV-8B Harrier II which has a length of 46-ft 4-in and a wingspan of 30-ft 4-in.

They almost certainly would be scrapped long before Harrier age.

 

[Christopher Wang]

Under Operation Sandy, a V-2 rocket was launched from the deck of the USS Midway (CVB-41) on September 6, 1947.

Were there ever plans to turn WWII aircraft carriers into launch platforms for the Polaris SLBMs?

 

[Lascaris]

How large is the crew that will be needed to man them though? HNLMS Karel Doorman, a Colossus-class light fleet carrier, had a complement of around 1,300. I have to wonder if the increased manpower and running costs would be considered bearable for the increase in capability.

I'd think that something in the region of 2000-2400 men should be about right. Which likely makes it too difficult to man for the smaller Commonwealth navies. So the only likely candidate in this case is France. Unless you can cut down the crew to something the size of Clemanceau which isn't necessarily likely.

From memory, the Alaskas single rudder had them turning as fast as a 500 000 ton supertanker. No idea if that's a nuisance for an aircraft carrier, against a battlecruiser ?

The Saipans were never sold to foreign navies, only the much smaller Independance class (2 for France, 1 for Spain: Bois Belleau, Lafayette and Dedalo. After dumping ours in 1962, we ingrate french nicknamed the spanish ship Pedalo : paddle boat, when our southern neighborgh used it from 1967 to 1989 with Harriers on deck).

On the other hand Essex class ships were offered in 1960 to Australia and... Spain in 1965. So why not the less useful Alaskas instead? Actually the most likely candidate may be no other than France. If the ships are available for disposal why not get one or both in place of the Independence class CVLs in 1951-53? Of course having a pair of 35,000t carriers that can likely last to the 1970s throws a spike in the wheels for the construction of Clemanceau and Foch... but may mean you get a single Verdun in their place?

 

[Moose]

The UK wouldn't want them, we had more carriers than we knew what to do with. The Dutch and Commonwealth Navies are all RN-adjacent, so a US ship isn't an immediately obvious choice if the RN's going to be handing out CVLs. France is really the only possibility, and would the USN be willing given it always seemed to cut France a bit too close to the bone during WWII (cf Richelieu completing her US refit with a gunnery radar set suitable for a PT boat)?

The US dumped a hell of a lot of resources into the Free Free French, including rebuilding a BB they had no plans for or tooling to support. Like the Indy-class CVLs actually used by the MN, I don't think there would be any resistance to sending a theoretical pair of Alaska class CVs so long as USN didn't want them.

 

[DWG]

The US dumped a hell of a lot of resources into the Free Free French, including rebuilding a BB they had no plans for or tooling to support.

There were also ‘political’ issues. The US Navy, which had been happy to share its latest technology with the Royal Navy because of the generosity of the latter in this respect during the period 1940-1, was less happy about according this concession to the French. As a result, Richelieu would be fitted with the latest AA weaponry, but the models of surveillance radar fitted were those standard on small surface escorts of destroyer size and below, and the US Navy refused point blank to release gunnery fire control radars as ‘too sensitive’. Thus, when she finally emerged from refit in late August 1943, Richelieu could steam and fight, and could defend herself against hostile air attacks. However, she could detect aerial attacks at only relatively short ranges and was dependent on her British consorts for long-range air warning. If battle were engaged with hostile surface units she would continue to rely on traditional optical fire control methods, which would be a particular problem in the conditions of poor visibility prevailing in northern waters. These limitations would have to be remedied over time by the British,

Jordan, John; Dumas, Robert. French Battleships, 1922–1956 (pp. 459-460). Pen & Sword Books. Kindle Edition.

 

[Scott Kenny]

Were there ever plans to turn WWII aircraft carriers into launch platforms for the Polaris SLBMs?

Basically everything with 35ft of hull depth had plans to install Polaris tubes. 1950s, the plan was to use Polaris just like Tomahawks now.

 

[Archibald]

Britain had 16 Colossus /Majestic 6 Illustrious 4 Centaurs and 2 Audacious : total 28 carriers.

 

[NOMISYRRUC]

So the discussion has come up on a different thread in alternatehistory.com. Say that because reasons the Alaska conversion to carriers went ahead in late 1941. Come the end of the war in 1945 you have two carriers, that overall are worse than the Essex, not standardized and possibly unneeded... if you are the USN and have two plus dozen Essex in addition to other ships. For everyone else they are 30,000t ships that can carry a larger air group than anything non-American still afloat.

Soo how do you dispose of them? Leave them to rust in reserve? Convert them to something else like prototype LPH? Make them command ships like the Saipans? Hand them over/sell them to allies for example France or Australia or perhaps even Britain?

Is CB-3 Hawaii completed as an aircraft carrier in your timeline?

 

[NOMISYRRUC]

Is CB-3 Hawaii completed as an aircraft carrier in your timeline?

Hawaii was laid down on 20.12.43, Midway was laid down on 27.10.43 and FDR was laid down on 01.12.43.

Therefore, a fourth Midway's laid down on 20.12.43 instead of Hawaii.

This would probably be CVB-44. IOTL it was cancelled on 11.01.43. ITTL Hawaii would be cancelled on 11.01.43 and on the same day the contract for CVB-44 transferred from Newport News to New York Shipbuilding Corporation.

 

[NOMISYRRUC]

So the discussion has come up on a different thread in alternatehistory.com. Say that because reasons the Alaska conversion to carriers went ahead in late 1941. Come the end of the war in 1945 you have two carriers, that overall are worse than the Essex, not standardized and possibly unneeded... if you are the USN and have two plus dozen Essex in addition to other ships. For everyone else they are 30,000t ships that can carry a larger air group than anything non-American still afloat.

Soo how do you dispose of them? Leave them to rust in reserve? Convert them to something else like prototype LPH? Make them command ships like the Saipans? Hand them over/sell them to allies for example France or Australia or perhaps even Britain?

Alaska was laid down on 17.12.41 and Guam was laid down on 02.02.42. Your POD of late 1941 is probably early enough to have both ships cancelled and have a pair of Essexes laid down on the same dates. @EwenS do you agree?

IOTL New York Shibuilding Corporation built one Essex. She was CV-20 Bennington, laid down on 15.12.42, launched on 20.02.44 and completed on 06.08.44. So she was launched 14 months after she was laid down and completed 20 months after she was laid down.

On that basis:

• An Essex built instead of Alaska would have been completed in August 1943 - Alaska was completed on 17.06.44.
• An Essex built instead of Guam would have been completed in October 1943 - Guam was completed on 17.09.44.
• An Essex built instead of Hawaii would have been completed in August 1945 - Hawaii was launched on 03.11.45.

However:

• Alaska and Guam were launched on 15.08.43 and 12.11.43 respectively.
• Hawaii was laid down on 20.12.43
• So it looks like Hawaii was laid down on the slipway vacated by Guam.
• Bennington was launched 14 months after she was laid down.
• On that basis:
  • The Essex built instead of Alaska would have been launched in February 1943.
    • And.
  • The Essex built instead of Guam would have been launched in April 1943.
• That would have allowed the Essex built instead of Hawaii to be laid down in May 1943 instead of December 1943.
• Advancing her completion from August 1945 to January 1945.

Although the abundance of Essex class aircraft carriers means that they decommission in 1947, don't receive the SCB.27 & SCB.125 refits, are re-designated aircraft transports (AVT) on 15.05.59 and in common with the other 5 Essex class AVTs are struck from the naval register 1964-69 and sold for scrap 1966-73.

 

[Dilandu]

The US dumped a hell of a lot of resources into the Free Free French, including rebuilding a BB they had no plans for or tooling to support. Like the Indy-class CVLs actually used by the MN, I don't think there would be any resistance to sending a theoretical pair of Alaska class CVs so long as USN didn't want them.

The problem would be French Navy not having resources to operate them.

 

[EwenS]

Alaska was laid down on 17.12.41 and Guam was laid down on 02.02.42. Your POD of late 1941 is probably early enough to have both ships cancelled and have a pair of Essexes laid down on the same dates. @EwenS do you agree?

IOTL New York Shibuilding Corporation built one Essex. She was CV-20 Bennington, laid down on 15.12.42, launched on 20.02.44 and completed on 06.08.44. So she was launched 14 months after she was laid down and completed 20 months after she was laid down.

On that basis:

• An Essex built instead of Alaska would have been completed in August 1943 - Alaska was completed on 17.06.44.
• An Essex built instead of Guam would have been completed in October 1943 - Guam was completed on 17.09.44.
• An Essex built instead of Hawaii would have been completed in August 1945 - Hawaii was launched on 03.11.45.

However:

• Alaska and Guam were launched on 15.08.43 and 12.11.43 respectively.
• Hawaii was laid down on 20.12.43
• So it looks like Hawaii was laid down on the slipway vacated by Guam.
• Bennington was launched 14 months after she was laid down.
• On that basis:
  • The Essex built instead of Alaska would have been launched in February 1943.
    • And.
  • The Essex built instead of Guam would have been launched in April 1943.
• That would have allowed the Essex built instead of Hawaii to be laid down in May 1943 instead of December 1943.
• Advancing her completion from August 1945 to January 1945.

Although the abundance of Essex class aircraft carriers means that they decommission in 1947, don't receive the SCB.27 & SCB.125 refits, are re-designated aircraft transports (AVT) on 15.05.59 and in common with the other 5 Essex class AVTs are struck from the naval register 1964-69 and sold for scrap 1966-73.

Firstly a correction. Bennington was the first of 5 Essex class laid down at the New York (Brooklyn) Navy Yard. (NYNY). 3 were completed and 2 suspended at the end of WW2.

The Alaskas were ordered from New York Shipbuilding Corp, Camden, New York, (NYSB) a commercial company. It specialised in building cruisers, of which the Alaskas were the largest. It never built an Essex. It did convert / build the CV-3 Saratoga and the 9 Independence class CVL as well as the two later Saipans (again based on a cruiser hull). Its next carrier was CVA-63 Kitty Hawk.

CV10 to CV-12 were ordered in May 1940 followed by CV-13 to CV-19 on 16 Aug 1940 (Friedman - US Carriers). The lead yard for the Essex programme was Newport News with Bethlehem Quincy close behind. But it was April 1941 before the design was finalised and the lead ship could be laid down at Newport News with CV-16 at Bethlehem following in July.

As for build times, be careful. Those actually achieved in wartime were not what was being predicted in 1941. In Nov / Dec 1941 an Essex was predicted to take 33-47 months to build. Those lengthy build times were what was spurring FDR to want the CVL programme that the USN only reluctantly accepted in Jan 1942.

Build times for the wartime completions ranged from 14 months for CV-13 Franklin (Newport News) to 27 months for CV-39 Lake Champlain (Norfolk Navy Yard - 7 months longer than their first Essex). The averages in the 5 yards involved ranged from 17 months (Newport News over their 8 completions) to 24 months (Norfolk Navy Yard over their 2 completions). So quite a bit of variation for multiple reasons.

CV-20 Bennington & CV-21 Boxer were ordered post PH as a part of a quick expansion but not laid down until Dec 1942 & Sept 1943. The next order arose in Aug 1942 (10 ships), following the big Pacific carrier battles earlier in the year. A further order of 3 was made in 1943 to cover expected attrition.

So what actually happened was something extraordinary that was not forseen in 1941 which is the POD for this exercise.

Due to a lack of capacity at BuShips, much of the design of the Alaskas was carried out by NYSB and was not completed and signed off by BuShips until May 1941.

So some questions:-
1. Why does the USN in mid / late 1941 decide it needs more than the 11 Essex class already on order? (remember the post PH response was to order only 2 more and embark on FDR's CVL proposal to get more carriers quickly. Remembering that at that stage an Essex was expected to take 33 months minimum to complete.)
2. How quickly can NYSB actually build an Essex, never having built one before? Part of that is the urgency perceived in Spring 1942 and the priorities for resources.
3. If the Alaskas are to be converted to carriers, how quickly can they be redesigned? Remembering that NYSB had the CVL programme on its plate at the time, for which they were responsible for much of the redesign work. And that programme was FDR's pet project.
4. How badly were the Alaskas affected by the 1942 steel shortage? (that was what led to the suspension of the 5 Montanas and 4 Alaskas in 1942). What were the priorities in allocating steel? Lot of escorts and then landing craft being ordered in 1942.

So I really can't see the USN dropping the Alaskas for more Essex in 1941. They felt that they had enough already. Otherwise why not order more than 2 in Dec 1941?

Converting the Alaskas to carriers is even more of a waste of resources. Historical evidence, even then, was that a ship designed from the keel up as a carrier, made for a more efficient carrier, than some battlecruiser / cruiser conversion except where needs must (Independence class).

If you really must have more carriers ordered in 1941, replacing the Alaskas with more Essex is the route to go, subject to one proviso. Did NYSB in 1941 have the facilities to build 2 Essex simultaneously? While they built Saratoga, which suggests the availibility of 1 slip of the appropriate size, did they have 2?

 

[BlackBat242]

Alaska-class carriers would be broadly comparable to Clemenceau & Foch - 839' x 108' flight deck (hull 791' 6" x 91' 9" waterline before bulging) Alaska; 869' x 168' flight deck (hull 781' x 104' waterline before bulging) Clem & Foch.

With a little bulging and an angled flight deck the Alaska-CV would be of similar displacement and overall beam - and would likely have similar air wing size.

They would certainly be an improvement over Colossus/Majestic class carriers - and over Saipans and Independences. If all 3 were ordered built/converted before launching they would form a decent class of ASW carriers in the USN or primary carriers for any other nation than the UK.

 

[BlackBat242]

The problem would be French Navy not having resources to operate them.

France operated Arromanches (1946-74), Bois Belleau (1953-60), La Fayette (1951-63), and Béarn (1948-60) at the same time, then Clem, Foch, and Arromanches at the same time from 1963 to 1974.

If the US held the 3 Alaska-CVs into the 1950s, even in mothballs, then France could potentially lease them instead of the two Independences they did historically - and when they are told there is not enough money for a 3rd new carrier (PA 58 or PA 59) they might get enough money for a modernization of the one with the least operational time to a similar standard as Foch & Clem.

 

[EwenS]

Hawaii was laid down on 20.12.43, Midway was laid down on 27.10.43 and FDR was laid down on 01.12.43.

Therefore, a fourth Midway's laid down on 20.12.43 instead of Hawaii.

This would probably be CVB-44. IOTL it was cancelled on 11.01.43. ITTL Hawaii would be cancelled on 11.01.43 and on the same day the contract for CVB-44 transferred from Newport News to New York Shipbuilding Corporation.

Now found a plan of the New York Shipbuilding Yard in WW2. It had 5 covered slips and a covered wet fitting out dock and a fitting out basin plus 5 uncovered slips. All the covered slips appear to be the same length and Saratoga was built on one of them as was Alaska, so it seems my question about slips capable of building an Essex has been answered, assuming they are not occupied by other constuction already laid down.

The Montanas were intended to be, and the Midways actually were, all built in dry docks, because by then they were so large that there were worries that they would be damaged by being launched conventionally from a slipway. Newport News had DD large enough for MIdway & Coral Sea (No.10 Dry Dock for the latter. AIUI built immediately pre-WW2). 5 DD for the Montanas were built in the Navy Yards (2 at NYNY, 2 at Philadelphia NY and one at Norfolk NY) and were completed in 1942/43 (which is what dictated the original laying down dates for the class). MIdway was built in one at NYNY. One of the Philadelphia DD was used to build 2 Baltimore class cruisers simultaneously starting 28 July 1943.

Looking at the plan I have of NYSB, it appears that they didn't have a dry dock at all. So your plan to put a Midway at NYSB doesn't work, so far as I can see. None of my references indicate where CVB-44 was originally planned to be built.

 

[NOMISYRRUC]

Link to Post 21.

So the short answer is, no, you don't. Fair enough.

We were both wrong about Bennington. It was built by Newport News.

When I checked my US Aircraft Carriers spreadsheet I discovered that I'd got more than a few builders for the Essex class wrong, which makes me think, what else have I got wrong?

The revised figures (in alphabetical order) are:

• 6 Bethlehem, Quincy - 5 completed.
• 6 New York Naval Shipyard - 3 completed.
• 10 Newport News - 10 completed.
• 5 Norfolk Naval Shipyard - 3 completed.
  • One of the cancelled ships was Reprisal.
• 5 Philadelphia Naval Shipyard - 3 completed.
  • One of the cancelled ships was Iwo Jima.

Although New York Shipbuilding Corporation didn't build an Essex IOTL, it did build all 9 Independence class and both Saipan class CVLs. For what it's worth of the 6 yards that built Essex class IOTL only 2 (Bethlehem & Quincy) had built an aircraft carrier before.

My figures for the building times for the 5 Essexes that were laid down in 1941 are that they took 16-20 months to build.

• 20 months Essex - August 1941-December 1942.
• 16 months Yorktown - December 1941-April 1943.
• 20 months Intrepid - December 1941 - August 1943.
  • The above were built at Newport News.
• 17 months Lexington - July 1941 - February 1943.
• 20 months Bunker Hill - September 1941 - May 1943.
  • The above were built by Bethlemem, Quincy.

However, in the light of me getting so many of the builders wrong, the building dates might be wrong too.

Maybe you're right that New York Shipbuilding couldn't have built Essex as fast as the OTL yards. However, I suspect that the would have been built in less than the 30 months that it took to build Alaska and Guam.

Oh! My copy of Conway's says that Alaska was launched on 03.11.45. I got the data for the class for the last post from Wikipedia which says she was launched on 03.11.45. (The other dates match.) Which is correct?

Maybe @Lascaris' proposal to build Alaska and Guam as aircraft carriers was inspired by the conversion of the 9 Cleveland class light cruisers to Independence class CVLs while they were building. As I've already written, all 9 Cleveland class were built by New York Shipbuilding and so were the 2 Sapian class CVLs.

 

[NOMISYRRUC]

Link to Post 25.

Fair enough.

The hull lengths that I have from Conway's 1922-46 are:

• 900ft waterline and 968ft overall - Midway.
• 850ft waterline and 888ft overall - Lexington.
• 820ft waterline and 888ft overall - Essex.
• 791ft waterline and 808ft overall - Alaska, which I've rounded down to the nearest foot.

The yard built Kitty Hawk after the war. Her lengths were 990ft waterline and 1,047ft overall. However, it might not have had a slipway/dry dock that long at the end of 1943.

According to Shipscribe:

• 07.08.42 - Contract for CVBs 41-44 awarded to Newport News.
• 12.08.42 - President Roosevelt placed a hold on construction of 4 CVB (41-44).
  • He wanted to build the smaller carriers in the program first.
• 29.12.42 - He allowed construction of CVB 41-42 (VCNO directive 4 Jan 43).
• 11.01.43 - CVBs 43-44 were cancelled.
• 21.01.43 - CVB-42 was transferred to New York Naval Shipyard.
• 26.05.43 - CVB-43 was reinstated under the 1945 building program.
• 14.06.43 - The new contract for CVB-43 was awarded to Newport News.

Source: https://www.shipscribe.com/navyrefs/usnprog/index.html

 

[DWG]

Britain had 16 Colossus /Majestic 6 Illustrious 4 Centaurs and 2 Audacious : total 28 carriers.

Plus Unicorn, Pretoria Castle, 3 Nairana Class, 3 Avenger (Charger) Class, 11 Attacker (Bogue conversions) Class, 23 Ruler (Bogue new-builds) Class, and 19 MAC ships. On the debit side, Pioneer (ex Mars) and Perseus (ex Edgar) of the Colossus class were maintenance carriers and unable to operate aircraft (unlike Unicorn, which could convert back and forth), while the Avengers, Attackers and Rulers were Lend-Lease and due to go back to the US.

 

[EwenS]

So the short answer is, no, you don't. Fair enough.

We were both wrong about Bennington. It was built by Newport News.

Nope. Bennington was built by New York Navy Yard. See Friedman US Carriers or check Navsource.

Aircraft Carrier Photo Index: USS BENNINGTON (CV-20)

It was CV-21 Boxer ordered at the same time as the Bennington that was built at Newport News.

When I checked my US Aircraft Carriers spreadsheet I discovered that I'd got more than a few builders for the Essex class wrong, which makes me think, what else have I got wrong?

The revised figures (in alphabetical order) are:

• 6 Bethlehem, Quincy - 5 completed.
• 6 New York Naval Shipyard - 3 completed.
• 10 Newport News - 10 completed.
• 5 Norfolk Naval Shipyard - 3 completed.
  • One of the cancelled ships was Reprisal.
• 5 Philadelphia Naval Shipyard - 3 completed.
  • One of the cancelled ships was Iwo Jima.

CV-50 to CV-55 never got beyond the stage of being a proposal for the 1945 construction along with CVB-56 & 57. Contracts had been provisionally awarded in Feb 1945 but the entire program was disapproved by FDR on 22 March 1945, so all further action was suspended with formal cancellation occurring in Aug 1945. See Friedman US Carriers. USN attention then turned to the "1945 Fleet Carrier" design.

CV-50 - Bethlehem Quincy
CV-51 & 52 from NYNY
CV-53 rom Philadelphia NY
CV-54 & 55 from Norfolk Navy Yard.

Although New York Shipbuilding Corporation didn't build an Essex IOTL, it did build all 9 Independence class and both Saipan class CVLs.

Because it was a cruiser specialist and both classes were based on cruiser hulls.

For what it's worth of the 6 yards that built Essex class IOTL only 2 (Bethlehem & Quincy) had built an aircraft carrier before.

You mean 5 yards building Essex class. Newport News, Bethlehem Quincy & the 3 US Navy Yards. Ignoring the conversions, only Newport News and Bethlehem Quincy had built carriers from the keel up, with the former being the specialist with 4 out of the pre-war 5.

My figures for the building times for the 5 Essexes that were laid down in 1941 are that they took 16-20 months to build.

• 20 months Essex - August 1941-December 1942.
• 16 months Yorktown - December 1941-April 1943.
• 20 months Intrepid - December 1941 - August 1943.
  • The above were built at Newport News.
• 17 months Lexington - July 1941 - February 1943.
• 20 months Bunker Hill - September 1941 - May 1943.
  • The above were built by Bethlemem, Quincy.

However, in the light of me getting so many of the builders wrong, the building dates might be wrong too.

Data seems right to within a month or two of my research. But I think you are missing my point. When Essex orders were being placed in 1940 the estimated build times were 3-4 years. Contractual completion dayes stretched from March 1944 to Aug 1946 and moved little until after PH. For example (info from official monthly USN reports to FDR):-

Essex - contractual completion date was April 1944. By Nov 1941 that had advanced just 3 months to Jan 1944. By May 1942 that had advanced to 31 Dec 1942.
Bon Homme Richard (renamed Yorktown) - contractual completion Sept 1944. By Nov 1941 that had advanced to April 1944. By May 1942 that had become the end of Feb 1943
Intrepid - contractual completion date Feb 1945. By Nov 1941 it was July 1944. By May 1942 it was April 1943.
Cabot (renamed Lexington) - contractual completion May 1944. By Nov 1941 it was Feb 1944. By May 1942 it was Jan 1943
Bunker Hill - contractual date Aug 1944. By Nov 1941 it was June 1944. By May 1942 it was March 1943.

By comparison the Alaskas were contracted to complete between April 1945 and Dec 1946.

Alaska - contractual date April 1945. By Nov 1941 it was Jan 1945. By May 1942 it was June 1944. Actual June 1944.
Guam - contractual date Aug 1945. By Nov 1941 it was March 1945. By May 1942 it was Aug 1944. Actual Sept 1944.

Everything was speeded up dramatically after PH but planning at the POD for this has to be based around the original estimated dates if it happens pre-PH to determine if it is a good idea or not. After all it was those dates that helped drive the Independence class program to get a lot more carriers quickly. The CVL completed in 1943 by the end of which there were 7 Essex completed v 0 in the origianal plan.

Maybe you're right that New York Shipbuilding couldn't have built Essex as fast as the OTL yards. However, I suspect that the would have been built in less than the 30 months that it took to build Alaska and Guam.

Building the ship is one thing. But how long to redesign? What gets priority for the design staff at NYSB (the CVL or the Alaska conversion)? How much structural work needs reworked (depends on when decisions are made). What priorities are given to them vis a vis a straight forward Essex build? All these things are pure speculation because it never happened.

Oh! My copy of Conway's says that Alaska was launched on 03.11.45. I got the data for the class for the last post from Wikipedia which says she was launched on 03.11.45. (The other dates match.) Which is correct?

Per Friedman & Navsource
Alaska laid down 17 Dec 1941, launched 15 Aug 1943 and commissioned 17 June 1944.
Guam laid down 2 Feb 1942, launched 12 Nov 1943 & commissioned 17 Sept 1944.

Maybe @Lascaris' proposal to build Alaska and Guam as aircraft carriers was inspired by the conversion of the 9 Cleveland class light cruisers to Independence class CVLs while they were building. As I've already written, all 9 Cleveland class were built by New York Shipbuilding and so were the 2 Sapian class CVLs.

And as I've noted NYSB built the Independence class because it already held contracts for building the Cleveland class cruisers on which they were based. 6 of those hulls had been laid down as cruisers (5 before PH) before the decision was taken to convert them to CVL. The two Saipans were meant to cover losses expected to occur. And with the experience of working the conversion of the Independence class it made sense for that contact to go to NYSB too.

 

[Lascaris]

Is CB-3 Hawaii completed as an aircraft carrier in your timeline?

The change is incidental, the TL is mostly European oriented. But one of the USN carriers is caught in the initial Japanese attack at Pearl and gets sunk. This causes enough of a panic that the proposed conversion of Alaska and Guam to carriers gets pushed forward by FDR alongside the Independence class CVLs. Hawaii is never completed instead the resources that went to her go to USS Kentucky which actually gets completed TTL.

 

[Cjc]

I thought the issue was engines more then anything else, as in the us couldn't build more Essex classes because it was taped out on engines and boilers, were as the alaska conversation wouldn't use any more of the bottle neck then there always was.