Earlier RN Armoured Carriers

[Triune Kingdom]

I was wondering just what it would take for the British RN to adopt the concept of the AFD/Armoured Box carriers earlier then they did IOTL?

Instead of having Ark Royal being what it was OTL, could we have ATL Ark Royal become the first of the British Armoured carriers, as RN comes to an conclusion earlier that "Bomber will Always Get Through" and that having "unarmoured" carrier deck is not worth carrying larger aircraft complement. ITTL, Ark Royal could be something very closely resembling OTL Illustrious Class, and its reduced AC complement could perhaps see it receiving a sister ship or two... In my mind I had an almost exact copy of OTL Illustrious, as Treaties are still in place and British keep to them, though understandably the ships would be somewhat less refined then their OTL counterparts, due to the timeframe in which they are designed and built. It however could make follow on carrier classes more formidable and refined, with perhaps Indomitable or even Audacious class coming into service earlier then IOTL.

A bit of digression, but it would also be a very nice to see just how aircraft procurement and design for the FAA develops if something like this occurs, and would there be any changes of note. Having their modern carrier(s) being more limited in number of aircraft carried, we could see some of the "multirole" designs come into play earlier then IOTL, with things like Blackburn Skua and Fairey Fulmar seeing service earlier, and because of that seeing some improved Marks come about. I do have a soft spot for many of FAA aircraft, and even many hated and ridiculed designs, could become much more useful if they were ordered earlier and went through some improvements. Blackburn Skua, could be "cleaned up" somewhat aerodynamicaly, and with more powerful engine, like Bristol Hercules, would be a much more capable aircraft. Same for the Fairey Fulmar, lighten the airframe, put a heavier weapons fit (like OTL nightfighter variants woth 4x0.50cal) and have a more powerful Merlin variant installed (Merlin 32?) and FAA would end up not with the best Naval Fighter, but at least a better one then they had to do with IOTL.

So, any takers?

 

[Zheng He]

The RN lost three carriers to submarines (including one escort carrier) and one to surface gunfire before they ever lost a carrier to air attack (little HMS Hermes and that wasn't until April 1942) so does it really make much of a difference?

 

[Peg Leg Pom]

The RN lost three carriers to submarines (including one escort carrier) and one to surface gunfire before they ever lost a carrier to air attack (little HMS Hermes and that wasn't until April 1942) so does it really make much of a difference?

It does if it causes the RN to demand more powerful aircraft engines to increase performance and reduce the handicap of smaller air groups. The Fulmar with a Griffin engine would be a quite formidable aircraft in 1940.

 

[Zheng He]

It does if it causes the RN to demand more powerful aircraft engines to increase performance and reduce the handicap of smaller air groups. The Fulmar with a Griffin engine would be a quite formidable aircraft in 1940.

But they didn't demand that OTL despite having fast good sized carriers (I'm thinking the Follies and the Ark).

Of note, like the OP, I have a soft spot for some of the early war FAA aircraft. The Skua was a good dive bomber (IOC two years before the Dauntless), it was miscast as a fighter and gets blamed for being below average at a job it should have never performed. The Fulmar - I would love to see how a smaller variant of that design with a single seat would perform.

 

[McPherson]

It does if it causes the RN to demand more powerful aircraft engines to increase performance and reduce the handicap of smaller air groups. The Fulmar with a Griffin engine would be a quite formidable aircraft in 1940.

i agree with this assessment, but then you need a LONGER and HEAVIER Fulmar which would not fit onto the British lifts of their current aviation support ships. This is a "small" problem that could be solved if the FAA was willing to hardstand the Fulmar out in the weather on the flightdeck.

But they didn't demand that OTL despite having fast good sized carriers (I'm thinking the Follies and the Ark).

Always have to think about the trade-offs and "why" the FAA did what it did. There were reasons the FAA wound up the way it did, aside from RAF incompetence.

 

[jsb]

he RN lost three carriers to submarines (including one escort carrier) and one to surface gunfire before they ever lost a carrier to air attack (little HMS Hermes and that wasn't until April 1942) so does it really make much of a difference?

Maybe since any modern ships might well take torps better than the older ships, and simply having more CVs will also help?

could perhaps see it receiving a sister ship or two...

 

[Peg Leg Pom]

But they didn't demand that OTL despite having fast good sized carriers (I'm thinking the Follies and the Ark).

Of note, like the OP, I have a soft spot for some of the early war FAA aircraft. The Skua was a good dive bomber (IOC two years before the Dauntless), it was miscast as a fighter and gets blamed for being below average at a job it should have never performed. The Fulmar - I would love to see how a smaller variant of that design with a single seat would perform.

Per the OP in TTL the Ark Royal is an Illustrious class with its small air group (the same number 36 as Furious). It's not unreasonable for the RN to take the attitude that "If we're going to carry fewer aircraft than other navies then we'll have to carry better ones" when issuing specifications for new aircraft as the alternative Ark Royal is laid down (1935). They've already made one change in policy by opting for an Armoured Carrier earlier than OTL so they could just as easily make another policy change with regards to aircraft.

 

[Simon]

I've always liked Just Leo's old idea of 'twinning' the nine-cylinder Perseus into an eighteen-cylinder that he christened 'Orion' which would give you an engine with a displacement of 3,040 in³ – roughly 240 in³ more than the Pratt & Whitney R-2800 – and hopefully 1,810 hp and rising as higher octane fuel and further developments are introduced. Would give you an engine that was more than sufficient for early war aircraft – fighter, dive bomber, and torpedo bomber – whilst simplifying logistics.

 

[Zheng He]

Per the OP in TTL the Ark Royal is an Illustrious class with its small air group (the same number 36 as Furious). It's not unreasonable for the RN to take the attitude that "If we're going to carry fewer aircraft than other navies then we'll have to carry better ones" when issuing specifications for new aircraft as the alternative Ark Royal is laid down (1935). They've already made one change in policy by opting for an Armoured Carrier earlier than OTL so they could just as easily make another policy change with regards to aircraft.

So was the 36 a requirement for the Illustrious class or did they not quite grasp the possible because ultimately they operated much larger air groups of 55+ and those were big planes like Corsairs and Avengers.

 

[Peg Leg Pom]

The 36 aircraft air group was because that was all that could fit in the hanger and due to (a) Conditions in the North Atlantic and (b) the assumption that the carriers would be in range of land based air power in the North Sea or Mediterranean and the bombers would get through the RN didn't use deck parks.

 

[edgeworthy]

Strictly speaking when Ark Royal was laid down the terms of the First London Naval Treaty were still in effect. Which means that Aircraft Carriers could be built up to 27,000 tons Standard displacement.
How much more AFD Carrier can be built with this?
(Are comparisons with a slightly smaller version of Taihō valid)

 

[Peg Leg Pom]

Strictly speaking when Ark Royal was laid down the terms of the First London Naval Treaty were still in effect. Which means that Aircraft Carriers could be built up to 27,000 tons Standard displacement.
How much more AFD Carrier can be built with this?
(Are comparisons with a slightly smaller version of Taihō valid)

They're valid, but eat up more of the treaty allocation in a single ship than the RN would like.

 

[michael1]

Strictly speaking when Ark Royal was laid down the terms of the First London Naval Treaty were still in effect. Which means that Aircraft Carriers could be built up to 27,000 tons Standard displacement.
How much more AFD Carrier can be built with this?
(Are comparisons with a slightly smaller version of Taihō valid)

Two issues, it may not be possible to build more carriers within the tonnage limit of the LNT (135,000tons). I don't know if the experimental carrier clause from the WNT still applies here. Secondly a reason for the armoured flight deck was that the increasing speed of aircraft and fixed detection range of an incoming raid (by eyeball until radar was developed) meant that interception was increasingly unlikely. The US and Japanese saw this too but in the wide open spaces of the Pacific could hope to hide their carriers much more effectively (this was why they operated single carrier groups). The Japanese eventually attempted to resolve this through multi-carrier groups with large CAPs that extended the detection range and sped up interception by having planes in the air. The true solution depended on radar.

The armoured flight deck was actually a dead end, the active protection of additional aircraft was better than the passive protection of armour once radar was developed. So replacing the Ark Royal with an armoured carrier is actually a reduction in RN efficiency from about 1940. Of course replacing Ark Royal with 2 lllustriouses is an improvement.

 

[Gokbay]

The problem is that the Royal Navy built Ark Royal with the assumption that it would fight Japan in the Pacific (in which they planned to use deck parks). Armoured Carriers are practical in the North Sea/Mediterranean where you can never be too far from land and as such will always be in range of the (superior to carrier based) land based planes. Not so much in the Pacific where a carriers air group are likely to be the only planes in range.

 

[Simon]

When discussing displacements the three things we need to know are what's the maximum allowed per ship by the various treaties, what if any total tonnage limit there is, and how many aircraft carriers the Royal Navy felt they needed to have in commission.

 

[Triune Kingdom]

Thank you all for your replies, but before everything, I do think I should perhaps change the Thread name. The subject matter could include more then just a single ship of a single class, and thread name should perhaps reflect that?

Main goal of the thread is to see just what changes are needed for the RN to go with Armoured Carriers from the start, completely skipping the "unarmoured" Ark Royal design. The argument that it would be very hard, if not outright impossible for a carrier to detect enemy aircraft raid in time (before RADAR) to deploy its own fighters, does sound like something (at least to me IMHO) which really makes a strong case in favour of the AFD, as it would stand the best chances of actually surviving the attack and replying in kind.

As far as the aircraft are concerned, I really was not trying to have FAA suddenly come up with anything new, but simply have some of the OTL designs come in earlier, be around in greater numbers, and perhaps undergo a bit more refinement then IOTL. As I said before, I have a (very large) softspot for WW2 FAA aircraft, and one does wonder what they could have been able to accomplish if there was more aircraft availlable, with improved performance when compared to their OTL counterparts. Fairey Fulmars Mk.IIs with 4x0.50cal, more powerful Merlin and provision for carrying larger bombs in service by 1941, things like that. Though I must thank @Zheng He and his excellent TL for introducing me to wacky FAA aircraft and RN Armoured Carriers in the first place, it is really a part of WW2 you do not hear about a lot.

Now, does anyone know how much of CV tons was Britain left according to the Naval treaties with before the OTL Ark Royal was built, and what would be done if they decide there is a need for more AFD CVs, and they find themselves without the required tonnage? Scrapping some of the oldest carriers or simply declaring them experimental? Ideally, I would like to see at least one more ALT Ark Royal (OTL Ilustrious) to beef up the number of modern CVs the British have at their disposal, but I am really not certain what could be done with older carriers and how much more use the RN can get out of them. I have run into similar threads before, so I will not go into too much detail here, but perhaps putting the three smallest and older CVs (Argus, Hermes and Eagle) in reserve/scrapping, could free up some 47,150 tons of displacement (going by Standard Displacement given by Wiki), enough for at least 3 illustrious class CVs if we take that IOTL they had enough displacement left over for Ark Royal (22,000 tons) without having to get rid of anything. Add perhaps limited modernisation of Courageus class trio as to take up the extra duties until AFD CVs come into play, plus whatever follow on Carrier class they lay down before WW2 starts, and RN would have a smaller CV fleet at its disposal, but certainly a more modern one.

Though, just how would the successor classes end up looking? Let us say RN has built 2, maybe 3 Illustrious CVs from period of 1935-1938, and by 1937 additional CVs (4 as IOTL) are laid down, so what exactly could we expect design wise, presuming that RN and FAA would still have doubts about low number of aircraft carried on board the newest CVs just entering service? Perhaps something like Indomitable Subclass, with its second smaller hangar, simply modifying the design of Illustrious, in an attempt to get the most out of a treaty compliant tonnage? It would be much quicker to (re)design and build then having to come up with brand new design, due to it being a relatively straightforward modification of an existing Carrier design.

 

[ArtosStark]

When discussing displacements the three things we need to know are what's the maximum allowed per ship by the various treaties, what if any total tonnage limit there is, and how many aircraft carriers the Royal Navy felt they needed to have in commission.

Well, @NOMISYRRUC is the guy to ask for that, in OTL, but to regurgitate what I remember from him:
1. Max allowed per ship in WNT was 27,000 tons. The British actually wanted it dropped to 22,000 at the 2nd LNT, partially as they thought they could build an effective design on 22,000 tons (Ark Royal). They managed to get it down to 23,000.
2. Total National Aircraft Carrier Tonnage was restricted to 135,000
3. During the 1920's the Admiralty wanted to build 5 17,000 ton carriers. This design morphed into the 22,000 ton Ark Royal. I am not sure what their desired total was at this time, but in the rearmament period the goal was for 14 carriers total. 8 for the fleet and 5 for trade protection (cruiser hunting) with the various squadrons around the world.

 

[Peg Leg Pom]

Though, just how would the successor classes end up looking? Let us say RN has built 2, maybe 3 Illustrious CVs from period of 1935-1938, and by 1937 additional CVs (4 as IOTL) are laid down, so what exactly could we expect design wise, presuming that RN and FAA would still have doubts about low number of aircraft carried on board the newest CVs just entering service? Perhaps something like Indomitable Subclass, with its second smaller hangar, simply modifying the design of Illustrious, in an attempt to get the most out of a treaty compliant tonnage? It would be much quicker to (re)design and build then having to come up with brand new design, due to it being a relatively straightforward modification of an existing Carrier design

For the second generation of AFD's it's likely the RN jumps straight to the Implacable Class. They still have to deal with the Japanese threat but with the advent of radar the likelihood of any enemy getting within gunnery range is hugely reduced. That means the walls of the hanger can have thinner armour, saving weight that can be used for a second hanger deck and an increased air group. The treaty is still in force so these hangers are low, but that's an acceptable compromise as the next generation of aircraft can be designed with that limitation in mind. (No one pre war was planning on buying foreign carrier aircraft).

 

[NOMISYRRUC]

Well, @NOMISYRRUC is the guy to ask for that, in OTL, but to regurgitate what I remember from him:
1. Max allowed per ship in WNT was 27,000 tons. The British actually wanted it dropped to 22,000 at the 2nd LNT, partially as they thought they could build an effective design on 22,000 tons (Ark Royal). They managed to get it down to 23,000.
2. Total National Aircraft Carrier Tonnage was restricted to 135,000
3. During the 1920's the Admiralty wanted to build 5 17,000 ton carriers. This design morphed into the 22,000 ton Ark Royal. I am not sure what their desired total was at this time, but in the rearmament period the goal was for 14 carriers total. 8 for the fleet and 5 for trade protection (cruiser hunting) with the various squadrons around the world.

That's more or less it.

In the first half of the 1930s they wanted 360 aircraft for the fleet aboard five 22,000 ton carriers carrying 72 each and the first of these ships was Ark Royal. 5 x 22,000 = 110,000 tons and they wanted the British and US quotas reduced to that in the Treaty that would replace the Washington and First London Treaties at the end of 1936.

By 1935 it looked like the tonnage quotas would be abolished by the next treaty (which they were) which allowed the Admiralty to consider carrying the Fleet's aircraft in a larger number of ships. Furthermore, the Torpedo-Spotter-Reconnaissance aircraft was replacing the earlier Torpedo Bomber and Spotter-Reconnaissance types which reduced the number of Fleet aircraft from 360 to 300.

This led to a new requirement for 8 fleet carriers accommodating 300 aircraft consisting of Ark Royal now rated at 48 aircraft and seven 23,000 ton armoured carriers. There would also be 5 trade protection (cruiser hunting) cruisers and one training ship which is how the 14 aircraft carrier requirement of late 1935 was arrived at. The 6 other aircraft carriers would consist of three 23,000 ton armoured carriers, Courageous, Glorious and Furious.

Therefore, building Ark Royal as an Illustrious is a non-starter. They can only build six 23,000 ton ships out of the 135,000 tons (actually they can only build five because 6 x 23,000 = 138,000) and six Illustrious class ships only carry 216 aircraft which is 144 short of the 360 required in 1934.

 

[CV12Hornet]

Now, does anyone know how much of CV tons was Britain left according to the Naval treaties with before the OTL Ark Royal was built, and what would be done if they decide there is a need for more AFD CVs, and they find themselves without the required tonnage? Scrapping some of the oldest carriers or simply declaring them experimental?

Per the Washington Treaty, Hermes, Eagle, Argus, and Furious all counted as experimental and could be replaced with new construction at any time. Keeping Furious in service as the only one of the four fast and capacious enough to be really useful leaves the British with 67,500 tons of aircraft carrier left to play with.