Axis Strategic Heavy Bombers?

[Lucky13]

How different would the air war of WWII have been, if the axis had been on par with allies when it comes to long range strategic bombers?

 

[SaparotRob]

The B-17B looks better in NMF.

 

[Just Schmidt]

Not a whole lot, unless on par includes industrial base and oil.

 

[ThomasP]

Maybe if they had them at the start of the war? But building a heavy bomber force would have been obvious to the Air Ministry/MOD and would have triggered an earlier response (of some sort) from the UK for sure, and probably from the French as well.

 

[z42]

Not a whole lot, unless on par includes industrial base and oil.

This is the crux of the issue. Had the axis powers had the industrial capacity to build and operate vast heavy bomber fleets, the war would indeed have looked very different. Also in other areas than just the air war.

 

[Shortround6]

From Wiki so take it as you will.
He 111
32 prototype aircraft
12 civilian airliners
808 pre-war aircraft
5,656 aircraft (1939–1944)

SO if we assume we can replace all of the 1939-44 He 111s with 4 engine bombers we get 2828 aircraft and if we count the 1169 He 177s as using 4 separate engines with less problems we might get just under 4000 4 engine bombers.

Not going to try to go through the Do 217s but the British built 15,886 four engine bombers. Americans built over 30,000 B-17s and B-24s.

Unless we really warp the reality of the German industrial complex the Axis are not going to get anywhere near the allied numbers.
One 4 engine bomber for every seven engine bombers the allies have?

And they sacrifice all the missions their twins did?

 

[Thumpalumpacus]

Not a whole lot, unless on par includes industrial base and oil.

... and fighter escorts with sufficient range. Ask Ira Eaker.

 

[tomo pauk]

From Wiki so take it as you will.
He 111
32 prototype aircraft
12 civilian airliners
808 pre-war aircraft
5,656 aircraft (1939–1944)

SO if we assume we can replace all of the 1939-44 He 111s with 4 engine bombers we get 2828 aircraft and if we count the 1169 He 177s as using 4 separate engines with less problems we might get just under 4000 4 engine bombers.

There was almost 15000 Ju 88s produced. Perhaps leaving anything above the 10000 pc mark to be made as 2-engined A/C, this ideally (it is rarely so, but still) leaves enough of 'war material' to make another 5000 of 4-engined bombers, for 9000 of 4-mots total.

Rarely contemplated advantage of really heavy bombers vs. 2-engined bombers is that one good heavy bomber will be carrying as much as 3 good 2-engined bombers. So that is a definitive advantage for a 4 mot. Heavy bombers usually have far better bomb bays (He 111 and Ju 88 were with very restrictive bomb bays) due to starting out with a more voluminous fuselage. It means not just that it will be easier to carry the really big bombs, but also means that there is no need to carry these outside the aircraft, so the mileage and cruising speed improve.

Another advantage is that a bomber force comprised mostly of big bombers will require half of the trained pilots when compared with a bomber force comprised of 2-engined bombers. Requiring thousands pilots less for the same on-target effect is a substantial saving for a country ill able to well train it's pilots.

A big bomber with 4-6 dedicated defensive gunners is in advantage vs. let's say He 111 with 4-6 defensive posts while having just 3 defensive gunners. It will also be much easier to outfit a big bomber with a tail turret with big firepower than it will be the case with the smaller bombers.

However - any daylight bombing operation will still require the presence of fighter escort.

 

[Shortround6]

We are getting into the details here.
The Axis two and 3 engine bombers did a lot of decent work and in some cases, better work, than a 4 engine aircraft would have. Not to mention that you can use two twins in different locations at the same time.
Better 2 engine aircraft would also have been an advantage. Axis failed in near spectacular fashion to come up with defensive gun set ups for multi-engine aircraft. At least in production quantities. As the Allies found out, even good defensive gun set ups are not enough without escorts. Axis defensive gun set ups were just good enough to keep the men from committing mutiny on the ground at take-off
Four engine bombers with "strategic" range tend to use two pilots, many twins use a single pilot (US was the major exception, followed by Japan with very long range twins). British were the exception the other way, Single pilots for four engine bombers. German twins tended to use one pilot. He 177 may have used 1 1/2 pilots? Control wheel could be swung over for relief or emergency. There was quite a bit of instruments/controls in the right seater area. And/or "strategic" range also means better navigation. The savings in training is not as clear cut as it may appear.
A lot of people overlook the range difference for the allies vs the Axis/Germans. Just due to the size of Germany Allied bomber aircraft have to fly further to hit many areas of Germany between 150-300 miles one way from the German border. Granted the Ruhr was close but there was a lot of Germany that was not easy to reach even for the French.
A problem for the British was that without French bases until May of 1940 Belgium and Holland were neutral and British bombers were supposed to fly around them to German targets, not over them, which added several hundred miles to projected missions. The Manchester was a response to a 1936 requirement that first flew in July 1939 so avoiding neutral airspace was a least given lip service.
Germans could base bombers close the border, since they were planning the land invasion to go right through Belgium and Holland, violating their airspace to bomb Britain was not a consideration. This was a 150 mile advantage (one way) depending on target in Britain.

German ability to use strategic bombing in Russia is an illusion. One that occupied a lot of German effort and thinking but was not founded in reality.
The Specification for the He 177 called for 2000lbs (? mayby 1000KG?) over 4160 miles (6700km?) max speed 335mph and 1-3 7.9mm mgs?
What they got (He 177V1) was plane that hit 286mph, cruised at 255mph and had a max range of 3105 miles (at speed ???) and was supposed to have three hand held 13mm mgs.
Even at the "cruise" speed of 255 mph that is a 12 hour flight for a single pilot, at less than 255mph???? Pilot endurance is critical. Single pilot??????
So was the ability to fly through over 1000 miles (one way) of potential hostile airspace (even if not well populated with defenses).
We haven't even gotten to navigation yet
What they got in the He 177A-1 was bit different. And the six 1000kg max bomb load may have been good for 745 miles.

Italians and Japanese don't have the needed engines.
American only got away with using 1200hp engines because they had the turbos. Without turbos they would have needed to change to the R-2600 engines with the changes in weight and fuel burn.

 

[tomo pauk]

Italians and Japanese don't have the needed engines.

What would be the needed engines? Italians made a lot of 3-engined bombers work well, so a 4-engined bomber with same engines' type is not a stretch.

Japanese certainly have the engines needed.

 

[Shortround6]

What would be the needed engines? Italians made a lot of 3-engined bombers work well, so a 4-engined bomber with same engines' type is not a stretch.

Japanese certainly have the engines needed.

May depend on what we mean by "strategic heavy bomber."

Italians were using 3 engines because they didn't have good enough engines to let them use only two engines.

Romanian SM 79 with a pair of Jumo 211s.

The SM 79 III didn't show up in numbers until 1943 with nearly 1000hp engines.
CANT Z. 1007 with 3 1000hp engines.

Yes you can make a plane with four 1000hp engines but is it really a strategic heavy bomber or is it a medium bomber with four smallish engines?

For the Piaggio P.108 things look better,
From wiki so again, take it as you will as this one is not attributed.
" The average Italian bomber cost around 2.1 million lire, the SM.79 cost 1.7 million, while the P.108 cost 5.2 million.[8] This would seem to favor the smaller bomber. But in a comparison to deliver a given weight of bombs at the same distance, the P.108B had the advantage. With a single squadron of nine P.108s capable of flying 1,100 km (700 mi) with 3,500 kg (7,700 lb), the estimated efficiency was comparable to a group of 26 SM.79s covering 1,000 km (620 mi) with 1,000 kg (2,200 lb). The total cost of each 'group' of aircraft required was about the same at 46.8 and 45.6 million lire respectively, but only 54 crew were required to man the P.108s compared to 130 required to man the SM.79s"

There may be a bit of cherry picking going on here.
It is using four 3200ci 18 cylinder engines so engine cost is a little high. If the SM 79s are using 9 cylinder engines the SM 79 are using 78 engines for 26 planes, the 9 P.108s are using the equivalent (in numbers of cylinders) to 72 9 cylinder engines.

For the Japanese do they have good enough engines early enough (before 1944) and in enough quantities to make any difference?
The Nakajima G8N Renzan is too late and trying to use turbo Homares was a operational nightmare waiting to happen.
A four engine giant Ki-21?

 

[z42]

For the Japanese do they have good enough engines early enough (before 1944) and in enough quantities to make any difference?
The Nakajima G8N Renzan is too late and trying to use turbo Homares was a operational nightmare waiting to happen.

Mitsubishi Kasei, entered service in 1941 with the twin engine G4M bomber. Initially 1530 hp, rising to 1800+ by the end of the war.

But what are the Japanese going to bomb with their four engined strategic bomber? They can't reach Hawaii, much less cities or industries on the US west coast. Grunts in the jungle on some island?

 

[tomo pauk]

Yes you can make a plane with four 1000hp engines but is it really a strategic heavy bomber or is it a medium bomber with four smallish engines?

Four 1000 HP engines can buy you a heavy bomber that is worth 90% of the Halifax I.

For the Japanese do they have good enough engines early enough (before 1944) and in enough quantities to make any difference?

Yes, they have good enough engines already in late 1941.

A four engine giant Ki-21?

Kawanishi seems the 1st to make modern and workable 4-engined military A/C in Japan, with two useful designs, so preferably having them to design a 4-engined job?

 

[marathag]

A four engine giant Ki-21?

Giant Ki-20 from Mitsubishi

updated with the Kasei to replace the Jumo 204 and other 1939 features.

 

[Shortround6]

Four 1000 HP engines can buy you a heavy bomber that is worth 90% of the Halifax I.

So 90% of not very good is OK?

My mistake, we just want "a strategic heavy bomber."

quality is not part of the requirement.

 

[tomo pauk]

So 90% of not very good is OK?

My mistake, we just want "a strategic heavy bomber."

quality is not part of the requirement.

What would be a very good strategic heavy bomber for 1939-40, on technology of the day?

 

[glennasher]

But what are the Japanese going to bomb with their four engined strategic bomber? They can't reach Hawaii, much less cities or industries on the US west coast. Grunts in the jungle on some island?

China comes to mind, if they get China out of the war, that frees up millions of men to fight in the island war.
That was the reason Roosevelt wanted the Hump opened up, to keep China in the war, so they could have it "somewhat easier" in the island campaigns.

Flying from Saigon or other places, they could play hell with the Brits in India, too. The Brits were already having a hard time keeping India in the war, the Indians wanted independence and weren't all that enthusiastic about helping the Brits keep their India colony colonized.

 

[Shortround6]

What would be a very good strategic heavy bomber for 1939-40, on technology of the day?

Probably the B-17, problem is it's window of opportunity is rather small. The B-17 was at least in small scale production, just about every thing else (4 engine anyway) was mostly prototypes so we can argue if a B-17B was better than a Whitley as a long range bomber in 1939. Of course we are also looking at 1939 fighters for interceptors.
By early 1941 the B-17C and D don't look so good. Fighters have gotten better for one thing.
The Halifax first flew on Oct 15th 1939, so it it a 1939 bomber? First production example flew on Oct 11th 1940, was used for testing, a 1940 bomber? First 6 aircrew are declared night operational on March 1st 1941 and first operation is on the night of March 10/11th, They suffer one loss, to an RAF night fighter. By the end of 1941 the RAF had 5 Halifax squadrons in service so there is no doubt that the Halifax was a 1941 bomber, it is earlier that is questionable.
The Stirling follows a similar path. First flight, was May 1939, but damaged on the first flight, 2nd prototype Flew in Dec 1939. 1st squadron formed in Aug 1940, unfortunatly both factories were bombed In Aug 1940 which set things back considerably, only 3 squadrons operational in 1941.
The Piaggio P.108 was even slower, first flight Nov 1939, but not delivered to an "operational " unit until 1941 and it was crashed in Aug 1941 by Bruno Mussolini. They had racked up 391 hours in 1941. first combat mission was June 6th, 1942. So what year was the P.108?

Back to the B-17, the first E was flown Sept 5th 1941, 1st squadron got one in Nov 1941, but by Nov 30th 1941 42 had been delivered (delivered to air force is not the same as issued to squadrons most of the time). B-17s were at Pearl Harbor (or arriving) on Dec 7th 1941. What year is the B-17? and obviously a B-17B is very different from a B-17F (May 30th 1942).

 

[ThomasP]

re

China comes to mind, if they get China out of the war, that frees up millions of men to fight in the island war.
That was the reason Roosevelt wanted the Hump opened up, to keep China in the war, so they could have it "somewhat easier" in the island campaigns.

Flying from Saigon or other places, they could play hell with the Brits in India, too. The Brits were already having a hard time keeping India in the war, the Indians wanted independence and weren't all that enthusiastic about helping the Brits keep their India colony colonized.

Good point.

For the PTO and CBI theaters this could have a serious impact. It would not (probably not?) be a war winner assuming other things went more or less as in the original time line, but the freeing up of the IJA forces and the required shipping needed for the war in China could have significantly increased the difficulty that the US and UK faced in their campaigns.

My understanding is that the US and UK faced only about 10-20% (depending on how you count it) of the Japanese ground forces between them. The other 80-90% were either in China or on the Japanese mainland.

How much would a freeing up of even 20-30% of the forces in China have on the war? IMO it would certainly have prolonged the war, unless the A-bomb had a similar impact in the alternate time line. The A-bomb, assuming the US/UK can employ it effectively in the alternate time line, would have ended the war anyway - the only question is how soon.

Could the USN have bypassed the Philippines - as they did many other Japanese held areas - or would there have been a much larger fight there? If they did not retake it, and could not afford to bypass it, what impact would that have on the original time line? Etc.

 

[EwenS]

China comes to mind, if they get China out of the war, that frees up millions of men to fight in the island war.
That was the reason Roosevelt wanted the Hump opened up, to keep China in the war, so they could have it "somewhat easier" in the island campaigns.

Flying from Saigon or other places, they could play hell with the Brits in India, too. The Brits were already having a hard time keeping India in the war, the Indians wanted independence and weren't all that enthusiastic about helping the Brits keep their India colony colonized.

Politically India was split. It was only the Indian National Congress that demanded independence before supporting the war. And the Govt in India moved quickly to quell that dissent in 1942. One arriving infantry division was deployed specifically for internal control in India for example. 60,000 INC leaders found themselves in jail, some until mid-1945. Over 3.35m Indians volunteered to fight in the Indian Army making it the largest volunteer army in history, and fighting for the Allies around the world. Even during the worst of the 1943 Bengal famine, the Govt in India retained control.

So what heavy bomber is to be used? The G8N Tenzan? Range (per Wiki) 2,451 miles. So combat radius c1,000 miles at the very most. Carrying what bomb load? What is the target?

Rangoon (Yangon) Burma, probably the most forward point with decent runways to Madras (Chennai) in eastern India is 1,100 miles.

Rangoon to Delhi (the seat of the Govt in India) is 1,450 miles.

You can look to the bombing of places like Singapore, Rangoon and Calcutta for signs of what might happen. In Calcutta in Dec 1942 there was a mass exodus of civilians (estimates range into the region of 2.5-3.5 million) from the city after the first Japanese bombing when the city was virtually defenceless and morale was poor following a string of defeats. But "panic" is not a word you see used in British (obviously!) or Indian accounts. The docks were virtually closed. BUT people did return. The docks did reopen when the aerial assault died out.

And unlike cities in the west, we are not talking about an industrialised nation. Most of the population lives out in the country in small villages with extremely poor communications.

IMHO to even begin to think about triggering a general revolt of the population in India is going to take a large scale, widespread and sustained bombing campaign. And the Japanese are still only going to be hitting a relatively small part of the sub-continent. And then, as other colonies across the Far East found, the Indians would simply have been swapping one master for another.