German Bomber design rational

[Robert Porter]

Out of curiosity I have always wondered why the Germans did not build and operate heavy bombers such as the B-17 and B-24? They certainly had the technical ability to create bombers with equal performance and payload. I have read several places that this was a decision made early in the war not to do so, but have never heard an explanation of the rational. Especially early in the Battle of Britain when heavy bombers could conceivably have caused a great deal more damage?

Or am I incorrect and they did operate such bombers?

 

[GrauGeist]

The Germans did have heavy bombers such as the He177 and the Do217 but they lacked a cohesive strategic heavy bombing strategy.

 

[Shortround6]

There are a lot of threads here that touch on that subject.
But basically nobody had large numbers of large 4 engine bombers in 1940.
From a production standpoint every 4 engine bomber was worth 2 twin engine bombers.

Everybody in the 1930s made 3 assumptions that proved false.
a. everybody over estimated the damage bombs would cause which made them think that bombers with small bomb loads would be effective.
b. everybody over estimated the tendency of the population at large (civilians) to panic under bombardment and riot in the streets bringing about the fall of the government/s under bombardment and the suing for peace.
c. everybody overestimated the ability of the bomber to "always get through" the enemy air defenses. This meant slow bombers and bombers with weak defensive armament were judged to be OK.

And we are back to the fast progress of aeronautical knowledge. What they could build in 1942 was not what they could build in 1938. and the engines they had in 1942 were not the engines that they had in 1938-39. This applies to all the combatants, not just Germany.

The Germans did build around 1200 He 177s

Two engines drove each propeller. They didn't use them all that often (for various reasons.) and they didn't become operational until 1942.

 

[Robert Porter]

The Germans did have heavy bombers such as the He177 and the Do217 but they lacked a cohesive strategic heavy bombing strategy.

I have read that part of the design criteria those bombers had to meet was a form of dive bombing or glide bombing in order to improve accuracy. But apparently they had little luck. If I am reading their specs right each had a bomb load capacity of around 2000 lbs or a little over, but they seem to have been primarily used on the eastern front and saw little action on the western front which speaks to your point of no cohesive strategic strategy.

 

[Robert Porter]

There are a lot of threads here that touch on that subject.
But basically nobody had large numbers of large 4 engine bombers in 1940.
From a production standpoint every 4 engine bomber was worth 2 twin engine bombers.

Everybody in the 1930s made 3 assumptions that proved false.
a. everybody over estimated the damage bombs would cause which made them think that bombers with small bomb loads would be effective.
b. everybody over estimated the tendency of the population at large (civilians) to panic under bombardment and riot in the streets bringing about the fall of the government/s under bombardment and the suing for peace.
c. everybody overestimated the ability of the bomber to "always get through" the enemy air defenses. This meant slow bombers and bombers with weak defensive armament were judged to be OK.

And we are back to the fast progress of aeronautical knowledge. What they could build in 1942 was not what they could build in 1938. and the engines they had in 1942 were not the engines that they had in 1938-39. This applies to all the combatants, not just Germany.

The Germans did build around 1200 He 177s

Two engines drove each propeller. They didn't use them all that often (for various reasons.) and they didn't become operational until 1942.

As I recall they did have designs/plans for the so called America bomber but it never saw production I think.

 

[Robert Porter]

There are a lot of threads here that touch on that subject.
But basically nobody had large numbers of large 4 engine bombers in 1940.
From a production standpoint every 4 engine bomber was worth 2 twin engine bombers.

Everybody in the 1930s made 3 assumptions that proved false.
a. everybody over estimated the damage bombs would cause which made them think that bombers with small bomb loads would be effective.
b. everybody over estimated the tendency of the population at large (civilians) to panic under bombardment and riot in the streets bringing about the fall of the government/s under bombardment and the suing for peace.
c. everybody overestimated the ability of the bomber to "always get through" the enemy air defenses. This meant slow bombers and bombers with weak defensive armament were judged to be OK.

And we are back to the fast progress of aeronautical knowledge. What they could build in 1942 was not what they could build in 1938. and the engines they had in 1942 were not the engines that they had in 1938-39. This applies to all the combatants, not just Germany.

The Germans did build around 1200 He 177s

Two engines drove each propeller. They didn't use them all that often (for various reasons.) and they didn't become operational until 1942.

I wondered about the actual effectiveness of bombing campaigns. I think they did a lot of good for the allies but less than was hoped for. Again, from what I have read most of that was due to greater than realized de-centralization of production facilities and the overall resiliency of the German production facilities. One can't help wonder what difference a cohesive bombing campaign by the Axis against the UK would have produced.

One story, have no idea how true, I have often read variants of it, was that Hitler was so incensed by an early bombing of Berlin that he ordered the Luftwaffe to cease attacking RAF bases and focus on cities. And that if he had not done so the RAF may well have been finished off.

 

[Shortround6]

An america bomber was pie in the sky wishful thinking. The B-29 could NOT fly from a North American base, bomb anything in Europe and return to a North American base. Americans started what would become the B-36 bomber project in April of 1941.

From Joe Baugher's web site.

"....design competition for a bomber with a 450 mph top speed, a 275 mph cruising speed, a service ceiling of 45,000 feet, and a maximum range of 12,000 miles at 25,000 feet. It had to be able to carry a 10,000 pound bombload a distance of 5000 miles away and return, and had to be able to carry 72,000 pounds of bombs over a reduced range. It had to be able to take off and land on a 5000-foot runway. These requirements were far beyond the state of the art at the time."

See: Convair XB-36 Peacemaker

Chances of Germany actually producing a plane that could perform such a mission during 1940-45 was effectively zero.

 

[Robert Porter]

An america bomber was pie in the sky wishful thinking. The B-29 could NOT fly from a North American base, bomb anything in Europe and return to a North American base. Americans started what would become the B-36 bomber project in April of 1941.

From Joe Baugher's web site.

"....design competition for a bomber with a 450 mph top speed, a 275 mph cruising speed, a service ceiling of 45,000 feet, and a maximum range of 12,000 miles at 25,000 feet. It had to be able to carry a 10,000 pound bombload a distance of 5000 miles away and return, and had to be able to carry 72,000 pounds of bombs over a reduced range. It had to be able to take off and land on a 5000-foot runway. These requirements were far beyond the state of the art at the time."

See: Convair XB-36 Peacemaker

Chances of Germany actually producing a plane that could perform such a mission during 1940-45 was effectively zero.

That was my feeling as well. I just don't see how it could have been accomplished with the available technology of the day. This is what I found on the concept, but consider the source. Amerika Bomber - Wikipedia

 

[Shortround6]

One story, have no idea how true, I have often read variants of it, was that Hitler was so incensed by an early bombing of Berlin that he ordered the Luftwaffe to cease attacking RAF bases and focus on cities. And that if he had not done so the RAF may well have been finished off.

The Germans might have been able to force the RAF to abandon the forward airfields (the ones closest to the coast) which would have put a much larger strain on the RAF but that is hardly finishing off the RAF. The 109s didn't have the range to escort the bombers much past London which left the RAF an awful lot of England to fly out of and engage the Germans.

 

[Greyman]

Everybody in the 1930s made 3 assumptions that proved false.
a. everybody over estimated the damage bombs would cause which made them think that bombers with small bomb loads would be effective.
b. everybody over estimated the tendency of the population at large (civilians) to panic under bombardment and riot in the streets bringing about the fall of the government/s under bombardment and the suing for peace.
c. everybody overestimated the ability of the bomber to "always get through" the enemy air defenses. This meant slow bombers and bombers with weak defensive armament were judged to be OK.

In a broad sense I don't think these are necessarily false. While it does seem that the effectiveness of conventional bombs was over-estimated before the war, one thing most academics were planning on was a no-holds-barred conflict where a good proportion of bombs loaded with some pretty horrifying chemical agents were very much on the table.

There are many that would argue that we might have seen things play out differently if one side decided to go all-out.

 

[Shortround6]

That was my feeling as well. I just don't see how it could have been accomplished with the available technology of the day. This is what I found on the concept, but consider the source. Amerika Bomber - Wikipedia

Again you have the disconnect between prewar thinking and actual results. The bomb loads they thought would burn an entire city were off by a factor of several hundred. The idea that even a few squadrons of bombers could destroy New York was ludicrous. Hundreds of fire trucks and thousands of firemen on duty at any given time mean that New York had as good or better fire protection than any city in Europe.

 

[Shortround6]

In a broad sense I don't think these are necessarily false. While it does seem that the effectiveness of conventional bombs was over-estimated before the war, one thing most academics were planning on was a no-holds-barred conflict where a good proportion of bombs loaded with some pretty horrifying chemical agents were very much on the table.

There are many that would argue that we might have seen things play out differently if one side decided to go all-out.

Well, to point "A" on my list, most German bombers were rigged to hold large numbers of 110lb bombs (He 111 could hold 32) and the British seemed to favor 250lb bombs in most 1930s designs even of 4 engine bombers. It was found that 500lb bombs were about the minimum effective against large buildings.
and again, the tonnage of bombs needed to really destroy parts of a city were underestimated by a huge factor. Damaging or destroying a few buildings per block was one thing, destroying entire blocks was something else. Damaging the water mains and firefighting ability was also harder to do than originally thought.
Point B, Few, if any, city populations ever rioted in the streets after a bomb raid or even series of raids in any country. There may have been thousands of refugees fleeing a city but not uprisings against the government.
ANd C. Most people (countries) gave up on un-escorted daylight bombing raids real quick and switched to night attacks if there was any real opposition in the air.

 

[wuzak]

I have read that part of the design criteria those bombers had to meet was a form of dive bombing or glide bombing in order to improve accuracy. But apparently they had little luck. If I am reading their specs right each had a bomb load capacity of around 2000 lbs or a little over, but they seem to have been primarily used on the eastern front and saw little action on the western front which speaks to your point of no cohesive strategic strategy.

No:

Heinkel He 177 - Wikipedia
"Bombs: Up to 6,000 kg (13,227 lb) of ordnance internally/7,200 kg (15,873 lb) externally or up to 3 Fritz X or Henschel Hs 293PGMs (w/FuG 203 KehlMCLOS transmitter installed)"

Dornier Do 217 - Wikipedia

• Max Load 4,000 kilograms (8,800 lb) internally & externally.
• Max Internal Load 3,000 kilograms (6,600 lb).

Of course the bomb load would vary with range.

 

[Robert Porter]

Again you have the disconnect between prewar thinking and actual results. The bomb loads they thought would burn an entire city were off by a factor of several hundred. The idea that even a few squadrons of bombers could destroy New York was ludicrous. Hundreds of fire trucks and thousands of firemen on duty at any given time mean that New York had as good or better fire protection than any city in Europe.

Oh I did not say I thought anything of the sort, just musing over what was being thought of. And the Amerika bomber was certainly beyond what WW2 Germany could produce especially with the constraints in place during the war on material and manufacturing capacity. Please don't jump to conclusions as I was honestly not saying it was practical nor possible just that it had been discussed.

 

[Shortround6]

I know you didn't say it but there are a lot of websites and at least one book if not more advancing the idea.
And don't get me wrong,the Americans managed to come up with a few (or more than a few) misguided ideas of their own.
As did the British.
Project for defeating German Beach defenses.

View: https://www.youtube.com/watch?v=1cyBcGDzQzI

 

[Airframes]

Another factor to remember when considering Germany's lack of 'heavy' or strategic bombers - the Luftwaffe was a tactical air force, who's role was supposed to be the support of the Army in the advance. It's organisation and equipment were built around this doctrine, with the resulting 'problems' encountered when operating in, or as close to, a strategic role.

 

[Shortround6]

This is another one of those things that is a near myth.
The Initial German bombers, the JU-52, Do 11/13/23 and the later Ju 86 were hardly "tactical bombers" nor were the early He 111s or DO 17s

Sure, they could be used to bomb supply points or bridges/road junctions and supply columns but they could also be used against most opponents, cities, factories and ports. Russia being an exception but then NOBODY had planes in 1937-41 that could fly distances needed to attack much of Russia is squadron numbers. (Whitley perhaps excepted)
The HE 111B as in the top photo used DB 600 engines (with carbs) and had 950hp for take-off and 910hp at 13,120ft. There is only so much you can do with engines of that power. max range with 1653lbs of bombs was 1030miles and range with max bomb load (3,307lbs) was 565 miles.
Max range of a JU-87B Stuka with an 1100lb bomb was 370 miles.
Tactical radius of these planes was ?????
A 400 mile radius was sufficient for a German bomber to hit most of France with the Brest peninsula and the Pyrenees mountains excepted. It was enough to reach all the way across Poland. And it was enough to Hit a good part of England. It is about 380-385 miles from Essen to Sheffield. It was just possiable to hit Liverpool from German soil with a 400 mile radius but the airfield would have been very close to the border. It was likewise just about 400-410 miles from German soil to Bergen Norway. It is just about 400 miles form the German border (now) to the Romanian border, flying over Austria and Hungary.
This means that the Germans could threaten most if not all of her likely enemies with air attack over a large percentage of their countries with planes having an operational radius of 400 miles or so. AS Germany acquired more territory (Austria, the Sudetenland, etc) the reach of the bombers increased.
As engines got more powerful the range and bomb load increased.

edit. top photo may be of a He 111E with 1010hp Jumo 211 for take-off. range 932 miles with 2200lb of bombs.

Given the continental distances the need for bombers with 600-800 mile of operational radius was actually minimal. And given the fact that it is about 700 miles from Warsaw to Moscow a plane that would be capable of strategic bombing against the Russians, even if Poland was captured, required a rather large leap in capability/engine power.

 

[Robert Porter]

It would seem the Luftwaffe was used in a role very much like the Army had wanted the Air Corps used for initially. But they somehow became stuck in that role whereas the Air Corps gradually gained more and more role autonomy as the war progressed. I think what I am understanding is Strategic vs Tactical uses of an Air Force? Is that correct?

 

[GrauGeist]

I have read that part of the design criteria those bombers had to meet was a form of dive bombing or glide bombing in order to improve accuracy. But apparently they had little luck. If I am reading their specs right each had a bomb load capacity of around 2000 lbs or a little over, but they seem to have been primarily used on the eastern front and saw little action on the western front which speaks to your point of no cohesive strategic strategy.

There was a fixation by the RLM that nearly everything should be dive-bomb capable. This ideology would cause a great deal of delays and frustrations with German aircraft design.

Regarding the He177's bombload you mentioned, the "Grief" carried 2,000 pounds of ordnance however it carried far more than that. It was originally conceived for the "Bomber A" proposal in 1936, where the requirements were to carry a 2,000 pound bombload a distance of 3,100 miles WHILE being able to maintain minimum speeds of 311 mph @ altitude so perhaps this is what you were thinking of?

The He177 went through a great deal of trial during it's development: the divebombing requirement - which cost alot of time and effort only to fail in the end, evaporative cooling tests, engines, landing gear and so on.

In the end, it proved itself to be a capable bomber, but it's main shortcoming was actually lack of fuel and more were lost sitting on the ground than in the air.

It's internal stores capacity was 13,230 pounds plus it had external hardpoints for additional ordnance including torpedoes.

 

[stona]

This is another one of those things that is a near myth.

I'm glad you said 'near myth'. Wever, responsible for the development of Luftwaffe doctrine, was certainly not an out an out follower of the doctrines developed on the similar theories of Douhet, Mitchell or Trenchard.

Luftwaffendienstvorschrift 16: Luftkriegsführung (Luftwaffe Service Regulation l6: Conduct of the Air War) on which Luftwaffe doctrine up to WW2 was based laid down three points:

1) subjugation of the enemy air force in order to achieve and maintain air superiority.

2) support of the army and navy (neither of which operated any aircraft independently).

3) attack against the enemy industry.

And in that order. Practically the 'subjugation of the enemy air force' was best achieved whilst it was on the ground. The second point already concedes a certain degree of subordination to the Army. The third point did not imply a huge strategic campaign of the type launched in 1943 by the Allies. It was closer to that launched by the Luftwaffe against, for example, British ports in 1940/41 or that launched less successfully by the British at the same time against oil and industrial targets in the Ruhr.
It is not true that no thought was given to a strategic capability, but the Luftwaffe was developed primarily as a tactical air force.
A very important difference to British doctrine was that the defence of the Homeland was primarily the task of the Flak arm, also controlled by the Luftwaffe, not the Army, with cooperation from the Luftwaffe.

As far as the adoption of, in Anglo-Americam terms, medium bombers, one should look at the lessons learned by the Luftwaffe in Spain, where the performance of the He 111 exceeded expectation and certainly influenced later planning. This was confused with competing requirements, but the Ju 88 was probably the outstanding result.

Cheers

Steve