Geoffrey Sinclair
Staff Sergeant
- 926
- Sep 30, 2021
Kesselring summarises the situation quite well, but overstates things at times Expecting a jump to designs weighing something like twice as much empty as the loaded weights of the latest types, like the Do17 and He111, would require much to go right. Remembering in the late 1930's the Wellington was a heavy bomber, staying there until the 4 engined types turned up, and expected to do lots of damage to industry it bombed. In the 1930's the Germans had to generate foreign sales to pay for much of the light metals and oil it used.
The mission defined the bomber, an Fw190 flying at night to drop a bomb on London is a strategic bomber, how many Japanese strategic targets did B-17 and B-24 missions attack? The Germans did not have tactical and strategic bombing as concepts. The damage to Britain in 1940/41 and the radio navigation systems indicates the Luftwaffe had the capability to undertake strategic bombing as per doctrine that allowed for it and other air operations depending on the situation. There is no fundamental reason why the missions actually flown by the German twin engined bombers in 1940/41 could not be flown by 4 engined types, being mostly air superiority and battlefield interdiction plus night strategic raids on Britain. The 8th Air Force dropped 81,803.5 tons of bombs on airfields for example. A larger aircraft has to fly higher to cut the risk of damage from ground fire, which reduces bombing accuracy but it normally carries more bombs, as noted larger transport aircraft is generally more efficient per unit of cargo, including personnel, fuel, build and maintenance costs.
The RAF and the USAAF came up with range/bomb load requirements that meant fitting 4 engines given the available power plants in the mid to late 1930's. The only attempt at a twin engine design that reached service had engine problems. The Germans wanted to bomb targets in the Urals and in any case solved the range issue by conquest until the USSR reorganised its war economy and the Luftwaffe really had to make the jump to B-29 class performance in the east to do strategic air warfare.
Going deep into enemy areas means damage to your units hurts more and the best you can normally hope for the personnel are captured, Germany was undertaking major submarine warfare, adding major strategic air warfare would be another significant drain on highly trained personnel.
As of 5 May 1940 Williamson Murray reports the Luftwaffe had 1,369 bombers and 321 long range reconnaissance.
Starting with money as short hand for resources. Build costs are subject to economies of scale, fewer designs the better but the greater the risk of large scale failure in combat. In 1944 the USAAF thinks it cost $204,370 for a B-17, $215,516 for a B-24, $192,427 for a B-26 and $142,194 for a B-25. Looking at the breakdown in costs the big one is engines, the B-17 engines cost on average $35,541 from 4 different price calculations, the B-24 $34,265, the B-25 $29,239 and the B-26 $44,403. In money terms in 1944 the 1,000 B-24 fleet translates to 1,120 B-26 or 1,516 B-25.
Britain June 1941 expected unit costs for proposed orders, in pounds,
44,250 Lancaster
43,752 Halifax
52,300 Stirling
38,100 Warwick
27,700 Wellington
18,950 Mosquito
On that basis a 1,000 Lancaster fleet translates to 1,597 Wellingtons, Stirlings even more.
Prices quoted for France 1945/6
37-40,000 Lancaster I
40,000 Halifax
15,000 Mosquito VI
16,000 Mosquito 30
16,000 Mosquito PR XVI
16,300 Mosquito PR.34
26,000 Wellington XIII
25,000 Wellington XIV
When it comes to twins versus four engine types the exchange rate is very design dependent. Assuming the proposed German design cuts numbers to 60% of the nearly 1,700 twin engine fleet that comes to around 1,000 aircraft. If the reconnaissance force had to be maintained at the 300 aircraft level that would have the bomber force. A smaller bomber force makes escorting easier, with the higher fighter to bomber ratio available. Germany had the capacity to build a large 4 engined bomber force in the late 1930's if a suitable design was available. It would obviously reduce the number of bombers but by how much depends on how much harder it was to build than mainly the Do17 and He111. Remembering in peace time defend the budget, wartime defend the country.
Timeline, Do17 requirement in 1933, first flights in 1934, He111 design began in 1934, first flight in February 1935, Ju86 first flight November 1934, Ju88 project work began in early 1936, first flight in December. Fw200 design began in 1936, first flight July 1937. Any 4 engine design would probably need to fly in 1935 or early 1936 to be in mass production in 1939 in the numbers needed to create a 1,000 strong force, and with designs that gave the Luftwaffe better bomb lift, easy for replacing the Do17, harder for the He111. He111 and Do17 production were each running at about 30 a month in 1937. The Do217 proposal in 1937, first flight in mid 1938, into service in 1941
Apart from his work on Luftwaffe doctrine General Wever was important as the glue holding together the Luftwaffe high command, afterwards feuding between the senior commanders increased to the point it harmed the air force, with a new chief of staff on almost a yearly basis to 1936 to 1939 doctrine and planning became more short term. Whether Wever could have arranged for a viable 4 engined bomber in 1939 performance terms arriving then is unclear as the designs actually ordered when he was around were for attacking locations in the Urals, a requirement which set the Do19 and Ju89 designs up to fail, to have a chance the specification needed to change to targets in Britain. If he had still been around the Luftwaffe would probably have more early war staying power and willingness to absorb the lessons from 1940 while being less interested in giving most bombers dive bombing capacity which reduced performance and delayed development.
Not sure how valid the following is, using wartime averages hides the big shifts in the fighting and given the half way points for bombs on Germany was end September 1944 for Bomber Command and mid November 1944 for the 8th Air Force flatters the loss figures.
Tons are long tons for the RAF and short tons for the USAAF, losses include accidents etc. on operations, sorties are attacking for the RAF and effective for the USAAF. All war Bomber Command and the 8th Air Force. First the raw numbers
Next some ratios, pounds dropped per attacking/effective sortie, read across the Wellington dropped 1.23 times the Mosquito bomb load per sortie, read down it took 0.81 Wellington sorties to equal 1 Mosquito
Now comes the ratios, losses per pounds dropped, read across the Wellington dropped 0.29 times the Mosquito bomb load per loss, read down the Wellington loss rate per pound of bombs dropped was 3.46 times the Mosquito
Now choose the best bomber.
The mission defined the bomber, an Fw190 flying at night to drop a bomb on London is a strategic bomber, how many Japanese strategic targets did B-17 and B-24 missions attack? The Germans did not have tactical and strategic bombing as concepts. The damage to Britain in 1940/41 and the radio navigation systems indicates the Luftwaffe had the capability to undertake strategic bombing as per doctrine that allowed for it and other air operations depending on the situation. There is no fundamental reason why the missions actually flown by the German twin engined bombers in 1940/41 could not be flown by 4 engined types, being mostly air superiority and battlefield interdiction plus night strategic raids on Britain. The 8th Air Force dropped 81,803.5 tons of bombs on airfields for example. A larger aircraft has to fly higher to cut the risk of damage from ground fire, which reduces bombing accuracy but it normally carries more bombs, as noted larger transport aircraft is generally more efficient per unit of cargo, including personnel, fuel, build and maintenance costs.
The RAF and the USAAF came up with range/bomb load requirements that meant fitting 4 engines given the available power plants in the mid to late 1930's. The only attempt at a twin engine design that reached service had engine problems. The Germans wanted to bomb targets in the Urals and in any case solved the range issue by conquest until the USSR reorganised its war economy and the Luftwaffe really had to make the jump to B-29 class performance in the east to do strategic air warfare.
Going deep into enemy areas means damage to your units hurts more and the best you can normally hope for the personnel are captured, Germany was undertaking major submarine warfare, adding major strategic air warfare would be another significant drain on highly trained personnel.
As of 5 May 1940 Williamson Murray reports the Luftwaffe had 1,369 bombers and 321 long range reconnaissance.
Starting with money as short hand for resources. Build costs are subject to economies of scale, fewer designs the better but the greater the risk of large scale failure in combat. In 1944 the USAAF thinks it cost $204,370 for a B-17, $215,516 for a B-24, $192,427 for a B-26 and $142,194 for a B-25. Looking at the breakdown in costs the big one is engines, the B-17 engines cost on average $35,541 from 4 different price calculations, the B-24 $34,265, the B-25 $29,239 and the B-26 $44,403. In money terms in 1944 the 1,000 B-24 fleet translates to 1,120 B-26 or 1,516 B-25.
Britain June 1941 expected unit costs for proposed orders, in pounds,
44,250 Lancaster
43,752 Halifax
52,300 Stirling
38,100 Warwick
27,700 Wellington
18,950 Mosquito
On that basis a 1,000 Lancaster fleet translates to 1,597 Wellingtons, Stirlings even more.
Prices quoted for France 1945/6
37-40,000 Lancaster I
40,000 Halifax
15,000 Mosquito VI
16,000 Mosquito 30
16,000 Mosquito PR XVI
16,300 Mosquito PR.34
26,000 Wellington XIII
25,000 Wellington XIV
When it comes to twins versus four engine types the exchange rate is very design dependent. Assuming the proposed German design cuts numbers to 60% of the nearly 1,700 twin engine fleet that comes to around 1,000 aircraft. If the reconnaissance force had to be maintained at the 300 aircraft level that would have the bomber force. A smaller bomber force makes escorting easier, with the higher fighter to bomber ratio available. Germany had the capacity to build a large 4 engined bomber force in the late 1930's if a suitable design was available. It would obviously reduce the number of bombers but by how much depends on how much harder it was to build than mainly the Do17 and He111. Remembering in peace time defend the budget, wartime defend the country.
Timeline, Do17 requirement in 1933, first flights in 1934, He111 design began in 1934, first flight in February 1935, Ju86 first flight November 1934, Ju88 project work began in early 1936, first flight in December. Fw200 design began in 1936, first flight July 1937. Any 4 engine design would probably need to fly in 1935 or early 1936 to be in mass production in 1939 in the numbers needed to create a 1,000 strong force, and with designs that gave the Luftwaffe better bomb lift, easy for replacing the Do17, harder for the He111. He111 and Do17 production were each running at about 30 a month in 1937. The Do217 proposal in 1937, first flight in mid 1938, into service in 1941
Apart from his work on Luftwaffe doctrine General Wever was important as the glue holding together the Luftwaffe high command, afterwards feuding between the senior commanders increased to the point it harmed the air force, with a new chief of staff on almost a yearly basis to 1936 to 1939 doctrine and planning became more short term. Whether Wever could have arranged for a viable 4 engined bomber in 1939 performance terms arriving then is unclear as the designs actually ordered when he was around were for attacking locations in the Urals, a requirement which set the Do19 and Ju89 designs up to fail, to have a chance the specification needed to change to targets in Britain. If he had still been around the Luftwaffe would probably have more early war staying power and willingness to absorb the lessons from 1940 while being less interested in giving most bombers dive bombing capacity which reduced performance and delayed development.
Not sure how valid the following is, using wartime averages hides the big shifts in the fighting and given the half way points for bombs on Germany was end September 1944 for Bomber Command and mid November 1944 for the 8th Air Force flatters the loss figures.
Tons are long tons for the RAF and short tons for the USAAF, losses include accidents etc. on operations, sorties are attacking for the RAF and effective for the USAAF. All war Bomber Command and the 8th Air Force. First the raw numbers
| type | tons | pounds | MIA+Cat E | Sorties | %loss | lb/sortie | lb/loss | Short ton/loss |
| Mosquito | 26,867.0 | 60,182,080 | 283 | 24,961 | 1.13 | 2,411.04 | 212,657.53 | 106.33 |
| Wellington | 41,823.0 | 93,683,520 | 1,523 | 31,657 | 4.81 | 2,959.33 | 61,512.49 | 30.76 |
| Whitley | 9,845.0 | 22,052,800 | 414 | 7,311 | 5.66 | 3,016.39 | 53,267.63 | 26.63 |
| Hampden | 9,115.0 | 20,417,600 | 499 | 10,259 | 4.86 | 1,990.21 | 40,917.03 | 20.46 |
| Stirling | 27,821.0 | 62,319,040 | 606 | 9,409 | 6.44 | 6,623.34 | 102,836.70 | 51.42 |
| Halifax | 224,207.0 | 502,223,680 | 2,113 | 66,456 | 3.18 | 7,557.24 | 237,682.76 | 118.84 |
| Lancaster | 608,612.0 | 1,363,290,880 | 3,726 | 135,445 | 2.75 | 10,065.27 | 365,885.90 | 182.94 |
| B-17 | 477,201.7 | 954,403,400 | 4,228 | 185,704 | 2.28 | 5,139.38 | 225,734.01 | 112.87 |
| B-24 | 209,949.0 | 419,898,000 | 1,630 | 78,914 | 2.07 | 5,320.96 | 257,606.13 | 128.80 |
Next some ratios, pounds dropped per attacking/effective sortie, read across the Wellington dropped 1.23 times the Mosquito bomb load per sortie, read down it took 0.81 Wellington sorties to equal 1 Mosquito
| Aircraft | Mosquito | Wellington | Whitley | Hampden | Stirling | Halifax | Lancaster | B-17 | B-24 |
| Mosquito | 1.00 | 1.23 | 1.25 | 0.83 | 2.75 | 3.13 | 4.17 | 2.13 | 2.21 |
| Wellington | 0.81 | 1.00 | 1.02 | 0.67 | 2.24 | 2.55 | 3.40 | 1.74 | 1.80 |
| Whitley | 0.80 | 0.98 | 1.00 | 0.66 | 2.20 | 2.51 | 3.34 | 1.70 | 1.76 |
| Hampden | 1.21 | 1.49 | 1.52 | 1.00 | 3.33 | 3.80 | 5.06 | 2.58 | 2.67 |
| Stirling | 0.36 | 0.45 | 0.46 | 0.30 | 1.00 | 1.14 | 1.52 | 0.78 | 0.80 |
| Halifax | 0.32 | 0.39 | 0.40 | 0.26 | 0.88 | 1.00 | 1.33 | 0.68 | 0.70 |
| Lancaster | 0.24 | 0.29 | 0.30 | 0.20 | 0.66 | 0.75 | 1.00 | 0.51 | 0.53 |
| B-17 | 0.47 | 0.58 | 0.59 | 0.39 | 1.29 | 1.47 | 1.96 | 1.00 | 1.04 |
| B-24 | 0.45 | 0.56 | 0.57 | 0.37 | 1.24 | 1.42 | 1.89 | 0.97 | 1.00 |
Now comes the ratios, losses per pounds dropped, read across the Wellington dropped 0.29 times the Mosquito bomb load per loss, read down the Wellington loss rate per pound of bombs dropped was 3.46 times the Mosquito
| Aircraft | Mosquito | Wellington | Whitley | Hampden | Stirling | Halifax | Lancaster | B-17 | B-24 |
| Mosquito | 1.00 | 0.29 | 0.25 | 0.19 | 0.48 | 1.12 | 1.72 | 1.06 | 1.21 |
| Wellington | 3.46 | 1.00 | 0.87 | 0.67 | 1.67 | 3.86 | 5.95 | 3.67 | 4.19 |
| Whitley | 3.99 | 1.15 | 1.00 | 0.77 | 1.93 | 4.46 | 6.87 | 4.24 | 4.84 |
| Hampden | 5.20 | 1.50 | 1.30 | 1.00 | 2.51 | 5.81 | 8.94 | 5.52 | 6.30 |
| Stirling | 2.07 | 0.60 | 0.52 | 0.40 | 1.00 | 2.31 | 3.56 | 2.20 | 2.51 |
| Halifax | 0.89 | 0.26 | 0.22 | 0.17 | 0.43 | 1.00 | 1.54 | 0.95 | 1.08 |
| Lancaster | 0.58 | 0.17 | 0.15 | 0.11 | 0.28 | 0.65 | 1.00 | 0.62 | 0.70 |
| B-17 | 0.94 | 0.27 | 0.24 | 0.18 | 0.46 | 1.05 | 1.62 | 1.00 | 1.14 |
| B-24 | 0.83 | 0.24 | 0.21 | 0.16 | 0.40 | 0.92 | 1.42 | 0.88 | 1.00 |
Now choose the best bomber.