RAN wants a carrier, 1934

[Admiral Beez]

I preface this that if you feel the RAN would never want nor get a carrier pre-WW2, this thread is not for you.

Contrarians; consider yourself forewarned. Now, everyone else, let's consider the below...

 

[Admiral Beez]

In 1933 the RAN began a modest expansion, including three CLs to serve alongside her two relatively modern CAs, along with the scrap iron flotilla of old ex-RN destroyers. Let's have the RAN find some significant additional funding in 1934 to procure an aircraft carrier, and orders the ship in 1935, for intended service in 1937.

What would the RAN get? If building new, what would the RAN specify? This would depend on the role for the carrier, presumably it would scout for the RAN's cruisers and protect trade/convoy routes.

Also, IMO, they wouldn't want a large Ark Royal type vessel, due to the manpower and operating expense, and the lack of drydocks in Australia for a ship if this size.

 

[mack8]

If second hand, maybe one of the Furious class? Or maybe the Hermes?

 

[Riain]

I'd suggest something to replace the HMAS Albatross seaplane carrier, perhaps the Hermes. IIRC the Hermes was slated to go too the RAN in 1942 but was sunk before it could be transferred..

 

[Admiral Beez]

If second hand, maybe one of the Furious class? Or maybe the Hermes?

That makes sense, since the RAN just bought a pile of old ex-RN destroyers, so they're not shy on buying previously owned ships.

Hermes is, IIRC already in the region at Singapore, so may be ideally located for passing onto the RAN since its FAA pilots and personnel could train the RAN. I'd suggest an extended drydock for refit, cutting down the top heavy island (though that internal space will need to be found elsewhere), squaring off the flight deck forward, removing the round down aft, and adding a crash barrier. Perhaps she can be sent to the US west coast to have the work done faster, as RN yards may be hard pressed and the expertise may not be available in Australia.

In this pic below from the Australian archives, we can imagine HMAS Hermes in RAN service.

The cheapest route would likely be Argus.

 

[Admiral Beez]

Next we need some aircraft. Britain may be too busy to provide Swordfish TSRs or Gladiator fighters, then both being introduced in 1936. Britain would likely offer Blackburn Baffin TSRs (IOTL, RNZAF bought up the FAA's stock in 1937) and Hawker Nimrod fighters (though only 92 were produced). I believe Hermes was still operating the Fairey Flycatcher into 1934 from Singapore, or that these had been moved to land service in Hong Kong. Regardless, all of these are nearly useless options.

So, we need an alternative. In 1936, CAC was founded to provide aircraft for the Australian air force, https://en.wikipedia.org/wiki/Commonwealth_Aircraft_Corporation A good start is likely a naval variant of the CAC Wirraway and the Boomerang fighter, provided they can be expedited to service by mid-1941. They both look ideally suited for wing folding.

We still need a torpedo bomber. And, there's always the option of buying USN types, as the French have been doing for Bearn.

 

[Cryhavoc101]

Okay firstly what is the expected mission of such a vessel?

Strike carrier?
Anti-commerce hunter?
other?

I dont think a Strike Carrier is practical - there is only 2 possible targets for such a vessel - Japan and the USA and they are not going to war with the USA and this would require something at least the size and capability of one of the Follies - which they would not be getting in the mid 30s

The role most of the RAN Cruisers played though - that is hunting commerce raiders and escorting troop convoys - would easily suit one of the existing older carriers or less likely a bespoke new build - perhaps this kick starts a 1934 pattern light fleet carrier design

Another possibility (and an often murdered Darling of mine) is rebuilding one or more of the older Cavendish class Heavy Cruisers into an Anti Commerce hunter

Initially it (or each if more than one) would only need a dozen or so Blackburn Baffins and maybe some Blackburn Sharks.

 

[NOMISYRRUC]

It's a better idea then their OTL aspiration for a battleship. It would be cheaper for a start, i.e. £7.5 million for a King George V or Lion against £4 million for an Illustrious plus more money for its aircraft.

 

[La Rouge Beret]

Another option would be to convert HMAS Albatross seaplane carrier into an escort carrier; I remember reading a proposed schematic for the conversion a couple of years ago. Now if the Australian government decides to undertake an expansionary fiscal policy during the Great Depression, then converting Albatross into a carrier seems reasonable within this context. Now with the lack of familiarity with the conversion I think an in service date of 1938 seems about right, which may very well change the aircraft to be used.

Perhaps production of fighter aircraft starts earlier for the CAC?

I actually had a draft TL that I had planned with a small carrier being operated by the RAN during WW 2, it fought in the Med and then returned to fight at Coral Sea as well.

Should really dust off my notes at some point.

 

[Admiral Beez]

It's a better idea then their OTL aspiration for a battleship. It would be cheaper for a start, i.e. £7.5 million for a King George V or Lion against £4 million for an Illustrious plus more money for its aircraft.

An Illustrious is likely not going to be made available, but how about an early mini-Ark Royal like the later HMS Unicorn, but with a boost from 24 to 27 knots.

HMS Unicorn was only 10 ft longer than the County-class heavy cruiser HMAS Australia, so should fit in existing drydock(s), and with two full length hangars, should support good aircraft ops and/or a credible airgroup size.

HMAS Unicorn with the BPF, third from bottom.

 

[NOMISYRRUC]

An Illustrious is likely not going to be made available, but how about an early mini-Ark Royal like the later HMS Unicorn, but with a boost from 24 to 27 knots.

HMS Unicorn was only 10 ft longer than the County-class heavy cruiser HMAS Australia, so should fit in existing drydock(s), and with two full length hangars, should support good aircraft ops and/or a credible airgroup size.

No. It's an Illustrious or nothing.

First because it is going to be a direct purchase from a British shipyard, not a transfer from the Royal Navy.

Second because the RN had originally planned for a mix of Illustrious class ships displacing 23,000 tons to work with the fleet and smaller ships displacing around 15,000 tons for trade protection. However, the estimated cost of an Illustrious carrying 36 aircraft was £4 million compared to £2.8 million for the Design F trade protection ship displacing 14,600 tons and carrying 15 aircraft produced in 1935. It was also slower and less well armed than an Illustrious. The larger Design M and N studies of 1937 were faster, better armed and capable of carrying 18 aircraft, but they were also more expensive than Design F.
Therefore the RN decided to build more Illustrious class instead of the 5-6 projected Trade Protection carriers because they put twice as many aircraft to sea for £5-6 million more.

Also the Washington Treaty and its tonnage quota of 135,000 tons for aircraft carriers in the British Empire was still in force in 1934. At that time the Admiralty wanted to squeeze the maximum number of aircraft out of the available tonnage with 5 Ark Royal class of 22,000 tons (because it wanted to reduce the tonnage quota to 110,000 tons) with 360 aircraft aboard. The aircraft carrier you propose would be vetoed by the Admiralty for making poor use of the available displacement. They would want the RAN to order an Ark Royal to replace Eagle or nothing.

The tonnage restrictions were lifted on 1st January 1937. You could have a RAN Illustrious class carrier laid down after that. However, it's likely that the RN would put one of the 4 ships of the class that they laid down in that year back to 1938 or 1939 for financial reasons and lack of industrial capacity.

 

[sonofpegasus]

For Pacific operations either an Ark Royal clone with a flat deck aft for maximum deck park and strike ranging or a Unicorn type baby Ark Royal would IMHO haver been the best option for the RAN in the late 1930's. The Baby Ark (unicorn size and style) should start the war with an air-group of around 50 aircraft. Not bad for 1040.

 

[hipper]

No. It's an Illustrious or nothing.

First because it is going to be a direct purchase from a British shipyard, not a transfer from the Royal Navy.

Second because the RN had originally planned for a mix of Illustrious class ships displacing 23,000 tons to work with the fleet and smaller ships displacing around 15,000 tons for trade protection. However, the estimated cost of an Illustrious carrying 36 aircraft was £4 million compared to £2.8 million for the Design F trade protection ship displacing 14,600 tons and carrying 15 aircraft produced in 1935. It was also slower and less well armed than an Illustrious. The larger Design M and N studies of 1937 were faster, better armed and capable of carrying 18 aircraft, but they were also more expensive than Design F.
Therefore the RN decided to build more Illustrious class instead of the 5-6 projected Trade Protection carriers because they put twice as many aircraft to sea for £5-6 million more.

Also the Washington Treaty and its tonnage quota of 135,000 tons for aircraft carriers in the British Empire was still in force in 1934. At that time the Admiralty wanted to squeeze the maximum number of aircraft out of the available tonnage with 5 Ark Royal class of 22,000 tons (because it wanted to reduce the tonnage quota to 110,000 tons) with 360 aircraft aboard. The aircraft carrier you propose would be vetoed by the Admiralty for making poor use of the available displacement. They would want the RAN to order an Ark Royal to replace Eagle or nothing.

The tonnage restrictions were lifted on 1st January 1937. You could have a RAN Illustrious class carrier laid down after that. However, it's likely that the RN would put one of the 4 ships of the class that they laid down in that year back to 1938 or 1939 for financial reasons and lack of industrial capacity.

if you are willing to be mischievous it's quite possible to Order the Unicorn earlier and not have her count against the RN's aircraft carrier tonnage. she was after all an aircraft carrier Depot ship rather than an aircraft carrier, And thus did not count against aircraft carrier tonnage
(at least that was what the RN said at the time, others may quibble)

Build her in the mid 30s as an auxiliary as a replacement for HNAS albatross with some RAAF aircraft on board and you have the best route to an Australian carrier in the 30s

Cheers Hipper.

 

[Pangur]

The RAN getting a carrier earleir may also have the knock on effect of having larger dry docks built that OTL

 

[NOMISYRRUC]

if you are willing to be mischievous it's quite possible to Order the Unicorn earlier and not have her count against the RN's aircraft carrier tonnage. she was after all an aircraft carrier Depot ship rather than an aircraft carrier, And thus did not count against aircraft carrier tonnage (at least that was what the RN said at the time, others may quibble). Build her in the mid 30s as an auxiliary as a replacement for HNAS albatross with some RAAF aircraft on board and you have the best route to an Australian carrier in the 30s

Cheers Hipper.

That could be done if the ship was built with a conventional superstructure and funnel on the centre line, but was designed so that she could be quickly converted to an aircraft carrier. The OTL Unicorn was built after the tonnage quotas were abolished so it didn't matter if the other navies thought she was an auxiliary or a proper warship. The Japanese did a similar thing with their submarine and flying boat depot ships that were designed for rapid conversion into aircraft carriers.

However, I still contend that an Ark Royal in the early 1930s (replacing Eagle which was allowed under the Washington Treaty) or an Illustrious after 1936 was more cost-effective.

 

[steamboy]

I'd say transfer the Hermes, in 34 there's not much yard space available and then have a plan to get a larger vessel in say 1940 when you've got an air crew and know how to use carriers. Failing that, convert the hawkins class into CVL's.

 

[Pangur]

I'd say transfer the Hermes, in 34 there's not much yard space available and then have a plan to get a larger vessel in say 1940 when you've got an air crew and know how to use carriers. Failing that, convert the hawkins class into CVL's.

If you go with the Hermes/1934 then thats going to change the aircraft fit out in the short term at least

 

[hipper]

That could be done if the ship was built with a conventional superstructure and funnel on the centre line, but was designed so that she could be quickly converted to an aircraft carrier. The OTL Unicorn was built after the tonnage quotas were abolished so it didn't matter if the other navies thought she was an auxiliary or a proper warship. The Japanese did a similar thing with their submarine and flying boat depot ships that were designed for rapid conversion into aircraft carriers.

However, I still contend that an Ark Royal in the early 1930s (replacing Eagle which was allowed under the Washington Treaty) or an Illustrious after 1936 was more cost-effective.

1. For the purposes of the Washington Treaty, the definition of an aircraft carrier given in Chapter II, Part 4, of the said Treaty is hereby replaced by the following definition:

The expression "aircraft carrier" includes any surface vessel of war, whatever its displacement, designed for the specific and exclusive purpose of carrying aircraft and so constructed that aircraft can be launched therefrom and landed thereon.

2. The fitting of a landing-on or flying-off platform or deck on a capital ship, cruiser or destroyer, provided such vessel was not designed or adapted exclusively as an aircraft carrier, shall not cause any vessel so fitted to be charged against or classified in the category of aircraft carriers.


3. No capital ship in existence on 1 April 1930 shall be fitted with a landing-on platform or deck.

A lawyer could make an argument that a depot ship is not a surface vessel of war it's an Auxillary so does not count. However what's sauce for the goose...

But practically the RN had the right to replace any of its experimental aircraft carriers with new build so in practise if Australia wants to pay for a new carrier in 1935, plan to replace say hermes by 1937 - 38 with the new Australian carrier. then don't scrap Hermes in 38

But what sort of ship could you build for 11,000 tonnes standard displacement in 1936 for about the same cost as a county?

Would it be much better than a Hermes?

 

[NOMISYRRUC]

1. For the purposes of the Washington Treaty, the definition of an aircraft carrier given in Chapter II, Part 4, of the said Treaty is hereby replaced by the following definition:

The expression "aircraft carrier" includes any surface vessel of war, whatever its displacement, designed for the specific and exclusive purpose of carrying aircraft and so constructed that aircraft can be launched therefrom and landed thereon.

2. The fitting of a landing-on or flying-off platform or deck on a capital ship, cruiser or destroyer, provided such vessel was not designed or adapted exclusively as an aircraft carrier, shall not cause any vessel so fitted to be charged against or classified in the category of aircraft carriers.


3. No capital ship in existence on 1 April 1930 shall be fitted with a landing-on platform or deck.

A lawyer could make an argument that a depot ship is not a surface vessel of war it's an Auxillary so does not count. However what's sauce for the goose...

But practically the RN had the right to replace any of its experimental aircraft carriers with new build so in practise if Australia wants to pay for a new carrier in 1935, plan to replace say hermes by 1937 - 38 with the new Australian carrier. then don't scrap Hermes in 38

But what sort of ship could you build for 11,000 tonnes standard displacement in 1936 for about the same cost as a county?

Would it be much better than a Hermes?

It's funny that you mention Hermes, because while I was changing the bedding it occurred that a more plausible POD would be for the Australians to order an improved Hermes in the 1920s from a British shipyard instead of the OTL Albatross. If the ship was welded and had higher pressure steam machinery it might be possible to get the displacement down to less than 10,000 tons so she would not be counted in the 135,000 tons. In the British OTL 1924 programme included some trade protection carriers displacing less than 10,000 tons. The TTL HMAS Albatross could be the prototype of those.

The alternative would be an enlarged Hermes with E class or County class machinery for a speed of over 30 knots. The extra power would require a larger hull to accommodate it, but that would also produce a longer flight deck and hangar. Although this ship would come out at over 10,000 tons and therefore would have to be counted in the tonnage quota there was over 20,000 tons left before the Ark Royal was built and she was completed after the tonnage quotas were abolished.

The downside of this is that the Japanese would build more Ryujo type carriers, which would cancel out any advantage to the British Empire in general and the RAN in particular.

I still think its better to order a second Ark Royal in 1934 to replace Eagle, but because the tonnage restrictions are abolished in 1936 it isn't necessary to scrap Eagle in 1938. This also forces the RAF to form 6 extra FAA squadrons between 1934 and 1938 for the extra ship's air group. That is very important because it increases the number of 800-series squadrons in 1939 from 15 to 21 plus a similar increase in the capacity of the training organisation, which in the long term is even more important. Early in the war IOTL the FAA often did not have enough aircrew and aircraft to operate the aircraft carriers it did have at full capacity. As part of this scheme the RAN and RN swap Albatross for Hermes, rather than the RAN operating the second Ark Royal. However, part of the agreement for Australia paying some of the cost of the extra Ark Royal is that it has to be deployed on the China Station.

 

[Peg Leg Pom]

How's this the R.A.N is lent H.M.S. Argus, which was in reserve anyway, for training, and orders an unarmoured version of the Illustrious class built to merchant standards. Effectively a Colossus class.