Do you know which Squadron was the first operational at more-or-less full strength with the Halifax MK II? The earliest I could find was in Apr'42.
According to RAF Squadrons by Jefford, Halifax I were used by
10 sqn December 1941 to August 1942, serving alongside Halifax II
35 sqn November 1940 to February 1942, being replaced by Halifax II from October 1941
76 sqn May 1941 to March 1942, being replaced by Halifax II from October 1941
I doubt a Halifax I was doing many operations in the second half of 1942.
102 squadron started to receive Halifax II in December 1941, last Whitley departed February 1942
78 squadron replaced its Whitley with Halifax II in March 1942.
Bomber Command says it first had an operational Halifax squadron as of 11 March 1941, another half squadron operational during June, by end July 2 operational squadrons, but really struggling to have more than single digit serviceable aircraft with operational crew on a given day until end October when it goes to around 12 aircraft plus crew. A third squadron declared operational 17 December, but back to 2 operational squadrons by end January 1942, back up to 3 squadrons on 31 March, to 4 on 26 April, to 5 in May, to 6 on 5 June, to 4 on 25 June, to 5 on 7 Jul, back to 6 on 3 August
To go any further means checking the squadron and aircraft histories.
https://www.lancasterbombers.net/form-78-aircraft-movement-cards/ has been taken down
https://bombercommandhistory.net/ is replacing it but does not have the movement cards available yet it seems.
Halifax Mark I
50 L9485 L9534
25 L9560 L9584
10 L9600 L9609
According to the RAF census as late as end February 1943 Bomber Command had 2 Halifax I in operational units, 12 in miscellaneous units, while another 5 were under test/repair/storage, 7 had been converted to instructional airframes, 59 lost.
Correction time, what I get removing the Hurricane mark I from the 1941 figures but writing the opposite
Hurricane, production / export by year
1940 2,521 / 245 (exports are April onwards)
1941 3,169 (including 607 mark I)/ 2,231
1942 3,067 / 3,421
1943 2,742 / 3,568
1944 688 / 494
1945 0 / 51
Imports from Canada, 419 mark I no engines (56 in 1940, 363 in 1941), 447 mark II no engines, 234 mark II with Merlin 28, mark II imports were 7, 426 and 248 from 1941 to 1943. Many of the Canadian imports were exported.
The thing is, did they need to build 2500 Hurricanes in 1941?
Since you have claimed I have no expertise and make things up stop using any data I provide, verify the information independently first.
Need to build ideas, 3,898 B-29 to end 1945 of which 1,090 overseas end August 1945, all cause losses 535 by end 1945, add say 500 for training in the US and about half of all B-29 were not needed, scrub the Bell and Martin lines and about halve the capacity of the Renton line. And so on for any war material in production late in the war, the B-29 being the most expensive.
The Hercules was struggling with reliability issues in 1940/41 the Merlin XX was more reliable.
They definitely didn't need to build any Defiants (no they weren't any use as night fighters either) and the Merlin XX didn't really work out for the Beaufighter as previously noted.
The lack of radar and Beaufighters and the performance of the Blenheim meant the RAF night defences used Hurricanes and Defiants with the occasional Spitfires. The Defiant had the advantage of two pairs of eyes with the gunner not losing part of their night sight to the lights from the instrument panel. Since the Luftwaffe broke off the attacks in May as the good weather was approaching, the non radar fighters were not given a chance the later Luftwaffe Wild Boar units took.
AIR 22/35 to 38, Fighter Command Operational Squadrons
| Date | Beaufighter | Beuf/Blen | Blenheim | Blenheim/Havoc | Defiant | Havoc | Havoc LAM | Havoc light |
2-Jan-41 | 0 | 6 | 0 | 0 | 3 | | | |
1-Feb-41 | 0 | 6 | 0 | 0 | 4.5 | | | |
1-Mar-41 | 0 | 5 | 0 | 1 | 4.5 | | | |
1-Apr-41 | 4 | 1 | 1 | 1 | 7 | | | |
1-May-41 | 4.5 | 0 | 1 | 0 | 7 | | | |
1-Jun-41 | 5 | 0 | 0 | 0 | 7 | 2 | 1 | |
1-Jul-41 | 6 | 0 | 0 | 0 | 7 | 2 | 1 | |
1-Aug-41 | 6 | 0 | 0 | 0 | 7 | 2 | 1 | 2 |
1-Sep-41 | 6 | 0 | 0 | 0 | 6.5 | 2 | 1 | 2.5 |
1-Oct-41 | 7.5 | 0 | 0 | 0 | 7 | 2 | 1 | 3.5 |
1-Nov-41 | 9.5 | 0 | 0 | 0 | 7 | 2 | 1 | 3.5 |
1-Dec-41 | 10.5 | 0 | 0 | 0 | 7 | 2 | 0 | 4.5 |
AIR 16/1036 For 1941, night, Fighter Command defensive sorties and combat casualties
January, 585 sorties, 1 Hurricane and 1 Defiant lost. AI sorties claims 0-2-1, cat's eye sorties claims 3-2-2
February, 589 sorties, no losses. AI sorties 20 contacts, 5 visuals, 3 combats, claims 1-0-2, cat's eye sorties 34 visuals, 10 combats, claims 3-2-3
March, 1,027 sorties, 1 Beaufighter lost. AI sorties 49 contacts, 35 visuals, 26 combats, claims 14-3-6, cat's eye sorties 29 visuals, 18 combats claims 8-3-4
April 1,697 sorties, 4 Hurricane lost. AI 538 sorties, 143 contacts, 73 visuals, 48 combats, claims 27-8-11, cat's eye 1,122 sorties 78 visuals, 48 combats claims 20.5-7-11, Havoc LAM 37 sorties, claims 1-1-0
May 2,357 sorties, 1 Spitfire, 3 Hurricane, 1 Defiant, 5 Beaufighter lost. AI 651 sortie, 203 contacts, 110 visuals, 80 combats, claims 34-9-18, cat's eye 1,652 sorties 143 visuals, 3 visual+searchlight, 126 combats claims 62-13-25, Havoc LAM 54 sorties, 3 firings claims 0-0-0
"Fighter nights", 5/6th, 7/7th, 7/8th, 8/9th, 10/11th.
June 1,650 sorties, 1 Hurricane, 1 Havoc lost. AI 550 sorties, 131 contacts, 62 visuals, 4 Visual+searchlight, 40 combats, claims 20-4-6, cat's eye 1,083 sorties 24 visuals, 3 visual+searchlight, 11 combats claims 7-0-3, Havoc LAM 17 sorties, 3 firings claims 0-0-0
"Fighter nights", 4/5th
July 1,365 sorties, no losses. AI 569 sorties, 82 contacts, 33 visuals, 25 combats, claims 20-2-1, cat's eye 790 sorties 22 visuals, 15 combats claims 6-1-4, Havoc LAM 6 sorties, 0 firings claims 0-0-0
"Fighter nights", 4/5th, 7/8th, 8/9th, 14/15th, 17/18th, these sorties claimed 0-1-2 (in cat's eye total)
August 1,092 sorties, 1 Beaufighter lost. AI 581 sorties, 60 contacts, 8 visuals, 5 combats, claims 2-0-2, cat's eye 509 sorties 10 visuals, 2 combats claims 1-1-0, Havoc LAM 2 sorties, 0 firings claims 0-0-0
September 710 sorties, no losses. AI 371 sorties, 41 contacts, 12 visuals, 5 combats, claims 2-0-2, cat's eye 328 sorties 8 visuals, 3 combats claims 1-0-0, Havoc LAM 11 sorties, 0 firings claims 0-0-0
October 1,137 sorties, 1 Beaufighter lost. AI 677 sorties, 114 contacts, 62 visuals, 6 Visual+searchlight, 29 combats, claims 9-3-11, cat's eye 424 sorties 14 visuals, 3 combats claims 2-0-0, Havoc LAM 36 sorties, 1 firings claims 0-0-0
November 770 sorties, 1 Hurricane lost. AI 428 sorties, 70 contacts, 21 visuals, 1 Visual no AI, 15 combats, claims 7-0-5, cat's eye 340 sorties 9 visuals, 1 combat claims 1-0-0, Havoc LAM 2 sorties, 0 firings claims 0-0-0
December 650 sorties, no losses. AI 440 sorties, 58 contacts, 13 visuals, 6 combats, claims 3-0-3, cat's eye 210 sorties 2 visuals, no combat, no LAM
John Foreman lists, quick hand count: Defiant claims in 1941, January 0-2-1, February 1-2-0, March 3-2-2, April 13-3-4, May 31-3-18, June 2-0-2, July 0-0-3, August 0-0-0, September 0-0-0, October 1.5-0-1, November 1-0-0 (day claim), December 0-0-0.
Cat's eyes in 1941 claims 114.5-29-52, of these Defiant 51.5-12-31
The RAF reports (AIR 20/2020) 9,051 British and 288 American aircraft on strength on 3 September 1939, a year later 16,782+790, two years later 23,510+2,188, three years later 34,743+4,128, the aircrew were being trained, the aircraft needed to be provided, while in 1941/42 only Fighter Command was reporting it currently had enough aircraft, but then not of high enough quality. The fighter force had 1,263 single engine aircraft on 3 September 1939, all British, on 3 September 1941 it was 4,862+84 single and 1,075+168 twin engine aircraft.
The US sent a lot of food and agricultural machinery to Britain under Lead Lease and much more food to the USSR on the same terms, meantime things like Spitfires and 8th Air Force bases in Britain were reverse lend lease. A big trouble was a western world geared to war with integrated Lend Lease had a series of economic hernias when the program and war ended so quickly. Lend Lease was far more than the weapons, in 1944 Britain had started the process of removing items from Lend Lease so it could restart export industries.
With the mid 1940 crisis the British government withdrew its financial limits on war spending, after that it was mathematics when the foreign exchange ran out. India gained local ownership of much of its industry, including the rail system, as Britain sold assets.
The 31st and 52nd Fighter Groups had P-39 before equipping with Spitfires in Britain. The 52nd seems to have had some P-40 when in the US.
Republic Evansville represents a nice case study, It only produced P-47, it did not exist in March 1942, 61,700 square feet in June, 301,000 in September, 662,500 in December, kept growing to 910,200 in December 1943, still growing until 1,090,400 in December 1944.
First production 10 P-47D in December 1942, first reports of work on production in June 1942
For June to December 1942,
Monthly thousand direct man hours on complete airframes and spare parts
1, 14, 30, 61, 113, 162, 247, total 638
Monthly direct man hours by phase of work.
12.3, 27.4, 46.7, 112.7, 163.5, 236.0, 247.0, total 845.7 thousand direct man hours, with the following percentage of outside production,
10, 20, 25, 30, 35, 66, 85
Production switched to the P-47N in July 1945 with 75 accepted, Monthly thousand direct man hours on complete P-47N airframes and spare parts, May to July 1945 were 16, 93, 226 total 335
Evansville was employing workers for 6 months before it built its first aircraft, the switch to the P-47N required two months of preliminary work. It helps explain why what was in production stayed in production, the costs of change were high and shows the time delays setting up new lines.