HMS Invincible

[NOMISYRRUC]

Wish Lists

I also have some information about what the naval aviation aspects of the rearmament programmes, i.e. what they wanted, rather than what they got, to contrast against your alternative history. Would you like me to to that?

 

[NOMISYRRUC]

The Wish Lists Part 1 - The Maritime RAF 1933-38

The Metropolitan parts of these schemes were completed on schedule, but the Overseas RAF only had 6 maritime squadrons at the outbreak of war, instead of the 13 planned in Schemes F and L.

The First Report of the Defence Requirements Committee. Not approved by the Cabinet, but the recommended completion date was 31st March 1939

Apart from the completing the expansion of the "52 Squadron" scheme of 1923 it did not recommend any increase in the size of the Metropolitan RAF. However, it did recommend the expansion of the Overseas RAF to 33 squadrons and 336 aircraft to "Show a tooth!" to the Japanese. If the Cabinet had approved this scheme the RAF would have had a total of 94 squadrons and 1,006 aircraft at the end of March 1939. The overseas portion of this included 88 maritime aircraft in 12 squadrons (60 landplanes in 7 squadrons and 28 flying boats in 7 squadrons. That would mean the total strength of the Maritime RAF would have been 104 aircraft in 16 squadrons (60 landplanes and 44 flying boats).

Expansion Scheme A approved by the Cabinet on 18th July 1934 for Completion 31st March 1939

However, the Government decided to concentrate its resources on expanding the Metropolitan RAF. Therefore the Home Based RAF was to be increased from the 50 squadrons and 548 aircraft that existed on 31st March 1934 to 84 squadrons and 960 aircraft on 31st March 1939. (Note that neither total includes No. 24 (Communications) Squadron.) There were to be 4 flying boat squadrons with 16 aircraft at both of these dates, but the number of torpedo bomber squadrons was to be increased from nil to 2 with 24 aircraft and 4 general purpose squadrons with 48 aircraft were to be formed. Therefore there was to be a total increase from 4 squadrons and 16 aircraft to 10 squadrons and 88 aircraft.

The RAF Overseas was to be increased from 24 squadrons and 268 aircraft to 27 squadrons and 292 aircraft. The maritime element consisted of 5 squadrons and 44 aircraft (2 torpedo bomber squadrons in Singapore and 3 coastal reconnaissance squadrons (one equipped with seaplanes) in March 1934. Under the programme it would actually decrease to 40 aircraft in 6 squadrons because the formation of a second flying boat squadron at Singapore was offset by the conversion of No. 202 squadron to flying boats.

Therefore the total increase was from 74 squadrons and 816 aircraft to 111 squadrons and 1,252 aircraft over 5 years (neither includes No. 24 Squadron). The maritime element of this would increase from 9 squadrons and 60 aircraft (24 torpedo bombers, 24 flying boats and 12 seaplanes) to 16 squadrons and 128 aircraft (48 torpedo bombers, 48 general purpose and 32 flying boats).

Expansion Scheme C Approved by the Cabinet on 21st May 1935 for Completion March 1939

The total strength of the RAF was to be increased to 150 squadrons with 1,804 aircraft by 31st March 1939, but the Metropolitan RAF would be increased to 123 squadrons and 1,512 aircraft by 31st March 1937. There was no change to the torpedo bomber force, but the general purpose force was to be increased to 7 squadrons and 126 aircraft (18 each instead of 12 each) and there were to be 6 flying boat squadrons with 36 aircraft (6 each instead of 4 each). That is a grand total of 15 squadrons and 186 aircraft. There was no change to the Overseas RAF so the grand total was now 21 squadrons and 226 aircraft (48 torpedo bombers, 126 general purpose and 52 flying boats).

Expansion Scheme F Approved by the Cabinet on 25th February 1936 for Completion 31st March 1939

What was about to become RAF Coastal Command would increase from 15 squadrons and 186 aircraft to 15 squadrons and 194 aircraft because the torpedo bomber force was increased from 24 to 32 because each of the 2 squadrons had its initial equipment increased from 12 aircraft to 16. The general purpose squadrons were now designated general reconnaissance squadrons. However, there was to be a massive increase in the strength of the maritime force overseas (which did not happen) to 13 squadrons and 168 aircraft. Had it been completed there would have been 80 torpedo bombers (5 squadrons of 16), 84 general reconnaissance aircraft (7 squadrons of 12) and 4 flying boats (one squadron of 4). That would have increased the total strength of the Maritime RAF to 28 squadrons and 362 aircraft (112 torpedo bombers, 210 general reconnaissance aircraft and 40 flying boats).

Expansion Scheme L Approved by the Cabinet on 27th April 1938 for Completion 31st March 1940

This scheme increased RAF Coastal Command to 19 squadrons and 281 aircraft. The 2 torpedo bombers and 7 general reconnaissance of the previous schemes were replaced by 9 combined torpedo-bomber-general-reconnaissance (T.B.G.R.) squadrons with 189 aircraft (21 each). 4 trade defence squadrons with 56 aircraft (14 each) were added (presumably the 4 auxiliary squadrons transferred to Coastal Command 1938-39). There was no change to the number of flying boat squadrons in Coastal Command. Overseas the number of squadrons was the same as Scheme F, but the number of aircraft was reduced from 168 to 158 because the torpedo bomber squadrons were reduced from 14 to 12 aircraft each. Thus the Maritime RAF would have had 32 squadrons and 439 aircraft (70 torpedo bombers, 189 TBGR, 84 GR, 56 trade defence and 40 flying boats) by March 1939 (if the overseas element of Scheme F had been completed on time).

Expansion Scheme M Approved by the Cabinet on 17th November 1938 for Completion 31st March 1942

Approved in the aftermath of Munich this scheme did not increase the projected strength of RAF Coastal Command, but the maritime force overseas was to be 17 squadrons and 204 aircraft. There were now to be 42 TBGR aircraft (3 squadrons), 96 general reconnaissance (7 squadrons), 42 amphibians (3 squadrons) and 24 flying boats (4 squadrons). The total strength of the Maritime RAF would then be 36 squadrons and 485 aircraft (231 TBGR, 96 GR, 56 trade defence, 42 amphibians and 60 flying boats).

 

[NOMISYRRUC]

The Wish Lists Part 2 - Maritime RAF Overseas in Detail

RAF Mediterranean

No. 202 Squadron was to have converted to a T.B.G.R. squadron in Scheme F. There were no changes until Scheme M. No. 202 Squadron would remain a flying boat squadron and a new T.B.G.R. squadron (No. 212) would be formed.

RAF Middle East

No.203 Squadron was to have converted to a landplane G.R. squadron and No. 229 (G.R.) Squadron was to be formed at Aden under Scheme F. There were no changes under the later schemes, except that Scheme J, which wasn't approved by the Cabinet, included a GR squadron of for Kenya.

RAF Far East

Ceylon was to have received general reconnaissance squadron under Scheme F. This was actually formed as No. 273 Squadron on 1st August 1939. It was equipped with 6 Vickers Vildebeests and was the last squadron formed by the RAF before war broke out. Nos. 255 and 256 (Flying Boat) Squadrons were authorised for Ceylon under Scheme M.

No. 145 (G.R.) Squadron was authorised for Penang (Alor Star) in Malaya under Scheme F. There were no changes under the later schemes.

Scheme A provided Singapore with 2 torpedo bomber squadrons (Nos. 22 and 42) and 2 flying boat squadrons (Nos. 205 and 230). Scheme F changed this to one flying boat, 2 TBGR and 2 general reconnaissance squadrons. Scheme J proposed a third GR squadron, but it was not approved until Scheme M. On completion Singapore would have had one flying boat squadron (No 230), 2 TBGR squadrons (Nos. 100 and 221 - No 36 would become a bomber squadron) and 3 general reconnaissance squadrons (Nos. 67, 92 and 205).

Hong Kong was to have 2 TBGR squadrons under Scheme F, but they were deleted under Scheme M. It was also to have had one GR squadron under Scheme F, but it was replaced by No. 222 Squadron with amphibians under Scheme M.

Gibraltar and Freetown

2 amphibian squadrons (Nos. 258 and 260) were to be part of Coastal Command in peacetime, but their war stations were Gibraltar and Freetown in Sierra Leone. They were not added until Scheme M.

Initial Equipments

Amphibians - 14 aircraft per squadron under all schemes.

Flying boats - 4 aircraft per squadron under Schemes A, C, F and L. 6 aircraft per squadron under Schemes J and M.

General Reconnaissance - 12 aircraft per squadron under Schemes F and L. 14 aircraft per squadron under Schemed J and M. The exception was No. 203 squadron in Iraq, which had 12 aircraft under Scheme M.

Torpedo Bomber and T.B.G.R. - 12 aircraft per squadron under Schemes A and C. 16 aircraft per squadron under Scheme F. 14 aircraft per squadron under Schemes J, L and M. However, some sources give them a strength of 16 per squadron in Scheme L.

 

[NOMISYRRUC]

ITTL will the reorganisation of the RAF from the Area system of ADGB to the Command system still take place in 19935/36 as OTL?

It's not up to me, but I don't see why not. It would be strange between 1919 and 1925 when there was only the Inland Area. After that it should have been ADGB (with one fighing and 3 bombing areas) and the Inland Area (army co-operation squadrons, training organisation and maintenance). ADGB would still be split into Bomber and Fighter Commands in 1936. The inland area would still become Training Command and throw off Maintenance Command.

The RNAS trained its own pilots, but (someone correct me if I'm wrong) after 1939 the RAF continued to train RAF personnel up to wings standard before going to a 700-series squadron for operational training. Does the RNAS continue to do that after 1918 in this time line?

Are the RAF still completely bomber centric?

Including the FAA the RAF had the equivalent of 90 squadrons in March 1933 (75 RAF proper, 12 FAA squadrons and 6 FAA flights). The 75 RAF proper squadrons included 7 with flying boats and 2 with torpedo bombers. Therefore 24 out of 90 squadrons (24%) were maritime units. In my opinon if they are taken out the RAF becomes if anything more bomber centric.

If the FAA are buying more aircraft then it is quite plausable for one or two manufactures to specilise in this field earlier and with more effect than OTL.

Not up to me, but it does happen in my alternative history of the RN between the wars. However, it also involves spending double the money on the RAF proper and civil aviation between 1919 and 1934.

 

[Lord Wyclif]

May 1935
Parliament confirmed that the Metropolitan RAF would be increased to 123 squadrons and 1,512 aircraft by 31st March 1937
No expansion was deemed necessary for the RNAS as at that time new aircraft were in the pipe line for Invincible, Illustrious, Formidable within the above time frame and a further new carrier operational by the end of the decade.
Supermarine Seafire deliveries had already started. 801 squadron were now undergoing flight training at Eastchurch, and 803 (HMS Illustrious) and 804 (HMS Formidable) aircraft were being constructed. The proposed rapid expansion of the RAF (Spitfire land version) would undoubtedly prevent any further orders for the RNAS for the foreseeable future.
Supermarine Walrus amphibian aircraft were ordered for the RAF and RNAS with deliveries to be started in 1936 for the Leander-class light cruisers that carried one Walrus each. The Royal Navy Town-class cruisers carried two Walruses each. Walruses also equipped the York-class and County-class heavy cruisers and some battleships.
Hawker received orders for 60 of their PV3 hurricane fighters with deliveries expected to begin by the end of the year and 4 squadrons to be fully operational by March 1937.
However F37/35 was issued and again RNAS technical experts worked closely with Supermarine, Hawker and Westland evaluating their differing designs.
HMS Invincible arrived in Portsmouth for a 12 month refit.

 

[NOMISYRRUC]

RAF Expansion Schemes

In the real Schemes A and C the FAA was to be expanded to 16 1/2 squadrons and 213 aircraft by 31st March 1939. In Scheme F approved in February 1936 provided for a FAA of 312 aircraft in 26 squadrons by 31st March 1939 and 504 aircraft in 42 squadrons by March 1942. As far as I know all of these totals were for carrier aircraft only.

Scheme F was by far the most important RAF expansion scheme so far because it provided for a massive increase in the scale of reserves. This led to the creation of the RAFVR and the building of the shadow factories. So if you are going to have and RNAS Volunteer Reserve, 1936 would be a good date to set it up.

 

[NOMISYRRUC]

As 1935 is the eve of the Rearmament Era in the real world, please can you do a state of play of the Royal Navy and RNAS at the end of 1935.

In the real world the British were building an average of 3 submarines, no battleships, one tenth of an aircraft carrier, 3 cruisers and 9 destroyers plus minor war vessels a year in the 10 years to 1935. The plan was to build 7 submarines, 2 aircraft carriers, 2 battleships, 7 cruisers and 16 destroyers plus more minor war vessels and auxiliaries a year in each of the 5 finanical years starting April 1936.

The above was beyond the capacity of the British armaments industry because it had been run down too far. The Hyperwar Website has a copy of the official history on British War Production on it, which explains things better than me.

However, you seem to be building an average of one battleship and one large aircraft carrier every two years. Going from one big ship a year to four would be much easier for the arms industry to cope with than from none to four. If you are going to build the same number of big ships from 1936 it would mean that they would be completed closer to schedule, which was 3.5 years for a battleship and 3 years for an aircraft carrier. That could make a lot of difference in 1940 and 1941.

 

[Lord Wyclif]

As 1935 is the eve of the Rearmament Era in the real world, please can you do a state of play of the Royal Navy and RNAS at the end of 1935.

In the real world the British were building an average of 3 submarines, no battleships, one tenth of an aircraft carrier, 3 cruisers and 9 destroyers plus minor war vessels a year in the 10 years to 1935. The plan was to build 7 submarines, 2 aircraft carriers, 2 battleships, 7 cruisers and 16 destroyers plus more minor war vessels and auxiliaries a year in each of the 5 finanical years starting April 1936.

The above was beyond the capacity of the British armaments industry because it had been run down too far. The Hyperwar Website has a copy of the official history on British War Production on it, which explains things better than me.

However, you seem to be building an average of one battleship and one large aircraft carrier every two years. Going from one big ship a year to four would be much easier for the arms industry to cope with than from none to four. If you are going to build the same number of big ships from 1936 it would mean that they would be completed closer to schedule, which was 3.5 years for a battleship and 3 years for an aircraft carrier. That could make a lot of difference in 1940 and 1941.

Will do an update for 31/12/35-01/01/36, but due to events I Ethopia September/ October Invincible's refit will be cut short and will be redeployed to the region under a new captain. Hope to have that ready sometime tomorrow evening.

 

[NOMISYRRUC]

Will do an update for 31/12/35-01/01/36, but due to events I Ethopia September/ October Invincible's refit will be cut short and will be redeployed to the region under a new captain. Hope to have that ready sometime tomorrow evening.

I look forward to it.

In an earlier post you said that you had made no changes to the Royal Navy's cruisers and destroyers.

However, as the RN has better carriers and more carrier aircraft exercises might show that the anti-aircraft armaments of the warships needed to be made more effective. That would mean more firepower and better AA fire control equipment. For example it might think again about giving its destroyers dual purpose guns.

Also the RN based its cruisers requirements on the number needed to protect trade and the number needed to scout for the fleet. The ratio was 5 cruisers for every 3 battleships, so if you have more battleships you need more cruisers.

Similarly destroyers requirements were based on the number needed to screen the fleet and the number needed for local defence and trade protection. So more battleships need more destroyers to screen them.

Cruisers and destroyer numbers weren't limited until the first London Treaty. You have relaxed the treaty limits for battleships and aircraft carriers so presumably apart from 8 inch guns and 10,000 tons there is no limit on the quality and quantity in your time line.

 

[Lord Wyclif]

Just to roughly up date other RN shipping. Under to Treaty's each old BB, starting with the 13.5" gun ships are being replaced by the new Lion/KGV treaty BB's on a one for one. These ships are armed as designed with 9 (3x3) 15" guns, 16 (4x2) 5.25" QF plus AA. I've introduced the 4.5"QF from 1933 for the Formidable, Anson & Howe. Again hull wise Invincible and Illustrious replaced Courageous and Glorious so hull numbers stay the same, however the 4 CVL/E's are a different story. Though they replace the seaplane carriers from 1922-26 1 per annum, therefor required building the destroyers Wayfarer,Woodpecker, Vantage, Votary, Warren, Welcome, Welfare and Whitehead to give each two destroyer escorts. 4", 4.7" & 5.25" gun mounting to be replaced by the 4.5"QF's in re fits from 1933 onwards.
OTL there were only 54 cruisers and 12 building, while there were only 169 destroyers and only 51 submarines. I've added a further 8 destroyers to this fleet. The RN always stated they required 70 cruisers but at £228 per ton for cruiser construction in 1930ish it is hard to figure where the cost for these extra 16 needed will come from. Then there will also be a need for more destroyers. I've tried to keep within realistic limits, but it has been said that the destruction of British shipbuilding began with the defence cuts in this era, so I'll try & throw in a few more cruisers & destroyers, keep the workers in employment & hopefully whilst saving the industry, keep so pesky liberal socialists away

 

[Lord Wyclif]

Captain Guy Royle was piped onboard. His XO Bruce Fraser along with Commander Arthur Seymour who was in charge of the air wing. In was a blustery and wet Monday morning. Cloud cover was low as the tugboats eased the mighty vessel from her mooring at 10:00hrs. News of Thursdays events had not yet reached the general public, but they Admiralty had ordered every available vessel to sea. Ships company lined the deck as tradition demanded, but the truth be known there was far more than one empty space.
Lunchtime found her mid channel steaming south westerly in clearing weather. Two miles of her starboard bow were the heavy cruiser Northumberland and Surrey and to the stern the destroyers Vanessa, Walpole, Wolfhound, Verity and Witch. It was here she began to receive the 12 Blackburn Baffin torpedo bombers of 813 squadron. Eventually the new Seafire squadron arrived early evening all were received without incident. At the start of the last dog another flight of aircraft was spotted. Illustrious's 803 squadrons Seafires. As they were recovering disaster struck. The tenth aircraft down nose dived on the traps and splinters of wooden propeller smashed across the flight deck. One of the bombheads received a fatal blow to the head.
Lunchtime Thursday October 10th saw the armada arrive in Gibraltar. A few days to collect stores the an easterly cruise into the Mediterranean. Marines of 9 RMLI were brought onboard to be transported to Alexandria to reinforce the garrison in case of Italian attack or an Egyptian uprising. Week commencing Monday 14th saw 813 squadron carried out a series of torpedo attacks on the battleships Queen Elizabeth and Valiant. Most of the attacks took place at night and two Baffins crashed with the lost of three aircrew.
She berthed in Alexandria early morning on Tuesday October 22nd.

 

[Lord Wyclif]

hristmas 1935 saw the most powerful armada assembled by the Royal Navy in peacetime safely anchored at HMS Nile. It included the battleships, Queen Elizabeth, Valiant, Revenge and Royal Sovereign as well as the battlecruiser Hood, the fleet carrier Invincible several cruisers and over a dozen destroyers. At either end of the canal the light carriers Vengeance and Vindictive with a destroyer and two sloops each patrolled the open seas.
Hawker Ospreys from 824 squadron supplied a flight to each ship. Vindictive was home to 813 squadrons Rippons and Vengeance had 812 also with Rippons giving each 20 aircraft (6+14). Round the clock airborne surveillance was maintained from RAF Aboukir with 142 squadron RAF in Hawker Harts and 801 & 803 RNAS squadrons Seafires. The naval pilots were extremely delighted they they were operating from a land base. Many of the young pilots were unnerved at the accident in October plus several of them had near misses whilst landing during the passage across the Mediterranean.
The bean counters back home were also delighted with thing going as they were. Ships in harbour weren't using any fuel and air cover was being supplied by land based aircraft so no expensive steaming into the wind at full speed during launching and landing operation. Considering the short flight times of the Seafires, usually only 90 minutes, this would have been a costly exercise.
Boxing Day two Seafires from Invincible's 801 were scrambled at 08:30 from Aboukir to conduct a patrol over the eastern med. 3 Italian merchant ships carrying military equipment, escorted by the cruisers Luigi Cadorna and the brand new Emanuela Filiberto Duca d'Aosla were due to enter the canal. As the small convoy was anchored awaiting the arrival of the navigation pilots and inspection by the canal authorities the two Seafires circled above at 2500 feet.
A fresh breeze was blowing, mainly westerly in direction causing a short moderate sea state.
Both Seafires had problems starting that morning, nothing more than usual, and it was put down to the weather conditions and after several false starts the engineers got them both flying. At 09:15 flight sergeant Evans noticed an engine leakage and felt the big V12 starting to miss fire. He informed the other pilot Flying Officer Johnston and they got in contact with the Vindictive 5 miles away for an emergency landing.
The Vindictive was proceeding at 12 knots and with the wind speed of 18 knots over the deck it was enough to let the two Seafires land. 4 Rippons were parked at the forward end of the flight deck as Evans approached, as he landed the carrier hit a larger than normal wave causing the Seafire to miss the wire and bounce along the deck. With the narrow undercarriage track, she flipped over port side taking two of the Rippons with her. The Vindictive immediately stopped and despite a frantic 5 hour search Flight Sergeant Evans body was never recovered.
On his first command of a large fleet carrier Guy Royle was off to a bad start. In the 2 months so far he had lost 2 expensive Seafires, 2 Baffins of his own plus the 2 Rippons and worst of all 5 members of his crew.

 

[Lord Wyclif]

New Years 35/36.

The aftermath of the Great War was that British policy was that there was not going to be any major war for the foreseeable future. Before the Great War Britain had been heavily and increasingly engaged in the international economy. Policy and institutions had played a central role in sustaining this internationalism, notably through continued adherence to the gold standard and to free trade. By the end of the 1920s Britain had clearly lost the international leadership it had exercised before 1914. Powerful lobby groups were formed between business and MPs, notably through organisations such as the Empire Industries Association and Leopold Amery’s Empire Economic Union resulting in an even more pro-commonwealth protectionism from the Ottawa Conference. The 5 years of its rule had a profound effect on British Maritime Policy. The fleet was needed to protect the trade routes, but more emphasises was laid on the Dominions to provide their fair share of the protectionist price. Whilst the RN was obliged under treaties the RAN, RCN etc were not. Many naval vessels had differing calibre weapons so a military cooperation conferences followed resulting in an Imperial Calibration of Weapons Treaty. Heavy cruisers would be rearmed with 7.2" guns with the Army following suit for its heavy artillery, light cruisers would have 5.5" guns along with the army's medium artillery regiments and AA/DP guns would be 4.5". Light artillery agreement would result in the introduction of the 25 pounder two years sooner. This rearmament programme should begin 1934-35 be completed by the end of the financial year 1939-40.

Thus the RN on paper had the following surface vessels:
CAPITAL SHIPS 14+5
HMS Hood, 8 x15", 12x5.5"
HMS Queen Elizabeth, HMS Valiant, HMS Warspite, HMS Barham, HMS Malaya. 8x15", 20x4.5"QF
HMS Nelson, HMS Rodney, (HMS Anson, HMS Howe being fitted out TBC 1937) (HMS Beatty under construction)
9x15" 16x4.5"QF
HMS Revenge, HMS Royal Sovereign, HMS Resolution
8x15", 4x4" QF
HMS Ramillies, (HMS Royal Oak in refit TBC 1938)
8x15", 8x4.5"QF
HMS Renown, (HMS Repulse in refit TBC 1937)
8x15", 20x4.5"QF
The reserve force consisted of a three 13.5"gunned ships until the new Admiral's were completed.
AIRCRAFT CARRIERS 5+5
HMS Invincible (8x4") (HMS Illustrious in refit TBC 1937), (HMS Formidable being fitted out TBC 1936) (HMS Ark Royal under construction)
HMS Furious.
12x4.5"QF
HMS Vindictive, HMS Venerable, HMS Vengeance (HMS Victorious in refit TBC1936)
4x4.5"QF
(HMS Argus & HMS Hermes in reserve until Ark Royal in commission)
HEAVY CRUISERS 15
Berwick, Cornwall, Cumberland, Kent, Suffolk, Devonshire, London, Shropshire, Sussex, Dorsetshire, Norfolk, Northumberland, Surrey, Exeter & York.
LIGHT CRUISERS 56
Newcastle, Southampton, Sheffield, Glasgow, Birmingham, Liverpool, Manchester, Gloucester, Belfast & Edinburgh.
Arethusa, Galatea, Penelope, Aurora, Polyphemus & Minotaur.
Leander, Orion, Neptune, Ajax, Achilles, Amphion, Apollo & Phaeton.
Emerald, Enterprise & Euphrates.
Danae, Dauntless, Dragon, Delhi, Dunedin, Durban, Despatch, Diomede, Daedalus, Daring, Desperate & Dryad.
Comus, Conquest, Champion, Cambrian, Canterbury, Castor, Constance, Centaur, Concord, Carlisle, Cairo, Calcutta, Caledon, Calypso, Caradoc, Capetown & Colombo.
DESTROYERS 126
V&W class 53
Scott class 12
Shakespeare 7
A-class 13
B-class 9
C&D class 14
E&F class 18
G-class 9 fitting out
H-class 9 under construction
SLOOPS 15 +2 under construction
The Dominions would also by 1939-40 contribute trade protection squadrons consisting of Trade Protection Carriers, Light Cruisers, Destroyers & Sloops depending upon each Dominion's GDP.
Again this is only background information, as the thread is about HMS Invincible, but the personalities, who brought about her construction, and their world views also will inevitably cause butterflies else where

 

[Some Bloke]

The standardisation of artillery with the Army is an interesting butterfly.

 

[sharlin]

Oh indeed..that would definately aid with weapon construction as long as they don't go bersker and produce a load of different calibers like the RN did.

 

[Lord Wyclif]

Oh indeed..that would definately aid with weapon construction as long as they don't go bersker and produce a load of different calibers like the RN did.

In the '30 you had 16", 15", 14" & 13.5" main guns then there were the 8", 7.5", 7.2", 6", 5.5", 5.25", 4.7", 4.5" and 4" etc and the army was trying to standardize the 4.5" & the 18 pounder to get the 25 pounder, so it would make sense logistically for the navy to do the same & even collaborate with the other armed services.

 

[Lord Wyclif]

The standardisation of artillery with the Army is an interesting butterfly.

One of many, with events on the horizon, & better inter-commonwealth economic co-operation easier logistics & better preparation resulting in many possible butterflies.

 

[Some Bloke]

One of many, with events on the horizon, & better inter-commonwealth economic co-operation easier logistics & better preparation resulting in many possible butterflies.

Coming from where?
Different decisions in Imperial conferences?
You also alluded to Dominion manned (built?) Trade Protection carriers, again coming from where?
A reinvigorated Committee on Imperial Defence?
If so then these butterfly into a WWI style Imperial War Cabinet.

You also mentioned the Royal Marines maintaining their artillery arm. Seeing as money is limited the changes give room for greater flexibility and expansion during the war even if the armed services aren't much better off in peace time.

Good work so far, looking forward to an update.

On another note, what are the tonnage figures for the Invincible class?
Larger than OTL's Courageous class I'd imagine seeing as they were converted from larger ships.

 

[Lord Wyclif]

Invincible class
Length 856 feet, beam 106 feet, draught 33 feet 9 inches.
Flight deck 836 feet x 106 feet above a hanger, 527 feet x 71 feet x17feet 2 inches served by a lift at either end.
Power was 160,000 shp and she was capable of 32 knots.
Armament as designed, 8x1 4.7" AA, 4x8 pop-poms. Refit 30-32, 7x8 pom-poms, 4x4 0.5" Vickers.
Aircraft 1st commission standard 36 aircraft air wing. 2nd commission standard 48 aircraft air wing. Surge air group 60-72 aircraft.
Displacement 39,400T standard (official 33,000T which does not include weight allowance under Ch. 11, pt. 3, Sec. 1, art. (d) of Washington Treaty for providing means against air and submarine attack. ) 46,900 T full load. Basically the G3 battlecruiser converted along similar lines as the American Lexington class.
Construction cost Invincible £3,680,400 Illustrious £3,698,560.
Formidable (sub class) £3,784,593. (8x2 4.5" DP guns )

 

[Some Bloke]

Seeing as they're bigger than OTL's Implacable class, I can see the 72 air group may become standard once aircraft production ramps up, and another refit.

Although seeing as the Implacable had 2 full length hangar decks and these ships presumably don't, were probably looking at 54 aircraft in hangar tops, with the rest deck parked.

On another totally unrelated note. Fighter development here is already nothing like OTL. I'm very interested to see what happens with the wider war in due course.