You're entirely right.
However, I see 308 Wimpys...& that's 308 more than were present OTL.
So, as they're replaced by Griffon Warwicks (& I presume they are)... Or is replacement entirely for losses, & those 308 have to be expended? In that event, I'm wrong again...
(How about, "Advice to High Wycombe: don't bomb sub pens, it's not productive"? {Yeah, getting a bit OT...
})
If you want better maritime patrol aircraft for the RCAF squadrons in Newfoundland in the first half of the war there are easier ways of doing it.
Option 1 - Build Short Sunderlands in Canada
IOTL the RCAF ordered a total of 40 Supermarine Stranraers from Canadian Vickers in four contracts. According to the Putnam's Supermarine Aircraft since 1914 the Canadian-built Stranraers had 960hp Pegasus X or 1,010hp Pegasus XXII engines.
The 3 Stranraers were ordered in November 1936. According to Canadian Military Aircraft Serials (C.M.A.S.) (
http://www.rwrwalker.ca/) the first aircraft (RCAF Serial 907 and constructor's number CV.184) was launched on 19th October 1938 and made its first flight on 21st October 1938. The Putnam's book says it was delivered on 9th November 1938. According C.A.M.S. the second aircraft was delivered on 30th November 1938 and the third wasn't delivered until 11th May 1939.
Judging by the taken on charge dates and constructors numbers on the C.M.A.S. website the next batches were for 4 and 3 aircraft respectively. The 4 aircraft in Batch 3 were taken on strength between 30th May 1939 and 5th August 1939. The 3 aircraft in Batch 4 were taken on strength on 31st August 1939, 27th September 1939 and 12th November 1939. That meant a total of 8 aircraft had been delivered before war was declared.
Christopher Shores in The History of the Royal Canadian Air Force says that the RCAF had 8 Stranraers on charge in September 1939. They equipped Nos. 4 and 5 (General Reconnaissance) Squadrons, RCAF. No. 5 Squadron was part of Western Air Command and No. 5 Squadron was part of Eastern Air Command.
My guess is that the 30 remaining aircraft were all part of the fourth contract. According to Putnam's Canadian Aircraft since 1909 the difficulty in getting material from UK slowed production in 1940. According to C.MA.S. the last 30 Stranraers were taken on strength by the RCAF as follows:
- 3 between 23rd October 1940 and 28th November 1940. (Putnam's Canadian Aircraft says 2 were delivered in the fourth quarter of 1940.)
- 3 between 6th February 1941 and 19th March 1941.
- 3 between 27th May 1941 and 26th June 1941.
- 9 between 4th July 1941 and 16th August 1941. (Putnam's Canadian Aircraft says 2 were delivered in third quarter of 1941.)
- 12 between 7th October 1941 and 17th November 1941. (Putnam's Supermarine Aircraft says the last Canadian-built Stranraer was delivered on 26th November 1941).
Meanwhile the British Air Ministry ordered the first 11 Short Sunderlands in March 1936. Therefore, I think the Canadian Department of National Defence could have ordered 3 Sunderlands from Canadian Vickers in November 1936. The only problem is that first British order was an "off the drawing board" purchase because the prototype hadn't flown yet and wouldn't until 16th October 1937. The first Short-built production Sunderland flew on 21st April 1938 and the type entered RAF service in June 1938.
Therefore, Canadian Vickers probably delivered its first Sunderland a few months later than the first Stranraer, but I think it would have caught up with the OTL schedule by the outbreak of World War II. The first 10 aircraft would be built with Pegasus XX engines producing 1,010hp like the early British built Sunderlands, but difficulties in obtaining these engines would result in the last 30 would have P&W Twin Wasps producing 1,200hp which had the side-effect of extending their endurance.
However, I think we can do
a lot better than that...
According to the Putnam's Canadian Aircraft book the Catalina was selected by the RCAF in December 1939, but negotiations did not start until the spring of 1940 and 731 were eventually built by Boeing Canada and Canadian Vickers as follows:
Air Britain's The British Air Commission and Lend-Lease says that 307 of the Catalinas were built on British account and 424 were built on Canadian account.
According to C.M.A.S. the RCAF received 55 Boeing Canada built aircraft that were taken on charge between 15th October 1942 and 15th July 1943. It also received 139 Canadian Vickers built aircraft that were taken on charge between 5th April 1943 and 3rd July 1944. The Putnam's on US Navy Aircraft says that the other 230 aircraft built by Canadian Vickers went to the USAAF as the OA-10A and the other 307 aircraft built by Boeing Canada went to the RAF, RAAF and RNZAF.
Meanwhile, the RAF had purchased a single Consolidated Model 28-5 to Contract 988730/39 that was delivered to the Marine Aircraft Experimental Establishment (MAEE) at Felixstowe in July 1939 with the British military serial P9630. The British Purchasing Commission ordered 30 Catalinas when war broke out and the total ordered before Lend-Lease was 174 aircraft in 5 contracts, which included 18 ordered for Australia, 50 for Canada and 40 for France. The first Catalina arrived in Australian on 2nd February 1941. The RAF received their first Catalina in March 1941. The RCAF received its first Catalina on 11th December 1941. According to the Air Britain book the RAF also received 275 Consolidated-built Catalinas via Lend-Lease along with 10 Consolidate Coronado and 5 Martin Maryland flying boats.
Quote from Air Britain's The British Air Commission and Lend-Lease
...the question of Canadian materiel support in war was discussed at the Imperial Conference of May 1937. However, due to a number of circumstances, progress prior to the outbreak of war was slow, primarily related to cost variation and the uncertainties of funding by the UK Government. Canadian industry remained interested, but in the event only one Canadian company (the National Steel Car Corporation) received an order, other than for aircraft, prior to the imminent outbreak of war (50,000 anti-aircraft gun shells).
It continued...
The Air Ministry, having kept a "watchful eye" on Canadian production of some "fifty-two" airframes of three types in British service for the RCAF (the Shark, Stranraer and Lysander II), and after protracted discussions/negotiations by "follow-up" British Air Missions to Canada (May-August 1938) led by Sir Samuel Hardman Lever, the Air Ministry placed direct contracts in November 1938, with Canadian Associated Aircraft Ltd. and the Canadian Car and Foundry Co. Ltd., for eighty Hapden and forty Hurricane aircraft respectively, together with a promised initial manufacture of 100 Stirling bombers. Sir Samuel Hardman Lever also led similar Air Missions to Australia and New Zealand.
However, ITTL the Canadians ordered Sunderlands in November 1936 instead of Stranraers. This led to the Air Ministry cancelling the Saunders Roe A.33 and Lerwick in December 1936.
The A.33 was the Company's rival to the Sunderland that had been designed to Specification R.2/33. The prototype flew on 14th October 1937 but was written off on 25th October 1937. This led to the cancellation of a production contract for 11 aircraft that had been ordered in March 1936.
The Lerwick was being designed to meet Specification R.1/36. The Air Ministry reserved serials for 22 aircraft in December 1936. The initial order 10 aircraft (including 3 to be used as prototypes) was increased to 21 aircraft in June 1937. The first aircraft was launched at the end of October 1938 and made its first flight early the next month. The 21 aircraft were delivered between March 1939 and June 1941.
Therefore, ITTL the Air Ministry places a direct contract for 10 Sunderlands from Canadian Vickers in December 1936 and this order was increased to 21 aircraft in June 1937. The Air Ministry would still buy the Consolidated Model 28-5 for evaluation, but the Air Ministry would order 30 Sunderlands from Canadian Vickers at the outbreak of World War II instead of the OTL contract for 30 Catalinas. These would be the first of 174 Sunderlands ordered from Canadian Vickers and Boeing Canada instead of the 174 Consolidated Catalinas ordered to British contracts. These would be followed by 290 Sunderlands instead of the 275 Catalinas, 10 Coronados and 5 Mariners obtained from the USA under Lend-Lease and the 731 Catalinas built in Canada IOTL.
Thus a grand total of 1,256 Sunderlands were delivered between October 1938 and the end of World War II and all because the Canadian Department of National Defence ordered 3 Short Sunderlands for the RCAF in November 1936 instead of 3 Supermarine Stranraers.
The other reason for cancelling the Saro A.33 and Lerwick was that the Air Ministry had subcontracted Walrus production to that Firm to allow Supermarine to concentrate on Spitfire production. This is what happened IOTL in the summer of 1940 . However, ITTL it happens in 1936. Therefore, the 285 Walruses that the Supermarine built 1936-40 IOTL were built by Saunders Roe ITTL. (Source: Putnam's Supermarine Aircraft since 1914)