If the US is neutral, how does the air war in Europe play out?

[wiking85]

Why use B-17s when longer range B-24 was the main heavy bomber used in PTO before B-29 arrived?

Did they have range before Okinawa fell? I know there were operations from China, but they were minor compared to the B-29 raids and IIRC the B-24 didn't have nearly as much defensive armament and usable payload at the ranges required even after Okinawa fell (being something like 900 miles from Tokyo, though about 400 from Kyushu).

Now that's just Wiki, e.g. nothing on KG 53 which did most of the launching. The first air launching of V-1s against England was on 7 Jul 44, that's before the launchpads were lost.

Fair point; it cost Germany about 70 He111 IIRC, so that likely happens here unless they use Do217s instead, which still would be costly.

 

[Juha]

B-24J had a range of 2100mls/3380km with 5000lb/2268kg bomb load, so it seems to have, only just, enough range. Of course, if they had to rely on B-24s, US might have taken one of the islands N of Iwo Jima instead of IJ.

Sure, B-24 wasn't a B-29 but could have firebombed at least some of the main Japanese cities.

 

[wiking85]

B-24J had a range of 2100mls/3380km with 5000lb/2268kg bomb load, so it seems to have, only just, enough range. Of course, if they had to rely on B-24s, US might have taken one of the islands N of Iwo Jima instead of IJ.

https://en.wikipedia.org/wiki/B-24_Liberator#Specifications_.28B-24J.29

Bombs:
Short range (˜400 mi): 8,000 lb (3,600 kg)
Long range (˜800 mi): 5,000 lb (2,300 kg)
Very long range (˜1,200 mi): 2,700 lb (1,200 kg)

Sure, B-24 wasn't a B-29 but could have firebombed at least some of the main Japanese cities.

Starting when? It was tried from China, but the results were underwhelming. Until Okinawa falls the B-24 cannot raid Japan and then it has a fraction of the payload at that range of the B-29 and much less defensive armament, so would be very vulnerable; for night attacks it lacks the excess fuel capacity to give it the reserve capacity to make it home in case of navigational errors. Plus how much extra would the radar navigation weight? If they're lucky they could manage 1000kg during daylight or less like Operation Tidewave, which would be insanely vulnerable to Japanese fighter defenses. They could raid Kyushu fine from Okinawa (B-17s too), but going after mainland Japan is too far, even for P-38 escorts.

Air raids on Japan - Wikipedia, the free encyclopedia
Historically they didn't really start until 1944 when the B-29 came online, except for minor raids like the Dolittle one.

 

[Garyt]

No. they were also adopted to outflank British AA belts, it was very easy to deploy AA defences against ground launched V-1s once one knew where the launchpatches were. And British AA was much more effective against V-1s than Germans were predicted.

The end run around AA defenses was a added benefit, the primary reason for air launching was the loss of the in range launch sites. Planning for such a possibility led to the development of air launches. And it (british AA) may have been more effective than the Germans anticipated, but it was by no means anything close to a sure fire defense. Even in Mid-Late 1944, when the defenses were at their zenith, about 30% would still make it thru.

Yet the US was about to invade when the Japanese surrendered. Why with the A-bomb, operation starvation, and B-29 raids? In 1944 the B-29 isn't ready, the B-17 cannot reach Japan even with Iwo Jima, the A-bomb isn't ready, operation starvation cannot be launched without the B-29, and the only apparent way to end the war was invasion?

Exactly. The Capitulation of Okinawa and Iwo Jima was not going to bring Japanese surrender. Perhaps over a long haul, a "siege" of Japan might have brought about their surrender - an Embargo of everything plus constant air attacks over Japan, from B-29's to carrier based fighter bomber strikes. But this would have taken a lot of time, months at least.

 

[RCAFson]

There's an interesting discussion of Tube Alloys here:

Tube Alloys and a British nuclear programme - Alternate History Discussion Board

 

[wiking85]

There's an interesting discussion of Tube Alloys here:

Tube Alloys and a British nuclear programme - Alternate History Discussion Board

Sure, a bunch of unsourced opinions; historically the British didn't think they could finish the bomb in time to make a difference, so were instead focused on building other weapons for the huge cost of the A-bomb project. The Manhattan Project for instance cost about as much as the US spent on all small arms in WW2. Perhaps Britain could have made something by 1945, but getting it over Germany and not having to worry about it being shot down is an issue. Also perception matters, if the British don't think they can get it done in time, as they don't have hindsight, then they wouldn't spend the resources to get it ready.

Also there is the engineering challenges that Britain will have to overcome at the cost of other projects; if they invest in Tube Alloy what aren't they building instead?
Tube Alloys and a British nuclear programme - Page 3 - Alternate History Discussion Board

Nevertheless enriching the Uranium to the correct proportion will be a huge technical challenge, even with gaseous diffusion. The Uranium for the Little Boy bom, was enriched by several processes, first by thermal diffusion (0,7% to 2%), then by gaseous diffusion (2% to 23%) and finally using the Oak Ridge calutrons (23% to c90%). Going all the way from 0,7% to 90% U235 using only gaseous diffusion is theoretically possible, but the engineering and scientific challenges are going to be massive for this to happen in a timely manner. While the choice of gaseous diffusion, was a lucky one on paper, there is a huge difference between science on paper, small scale science in a laboratory and then large scale industrial production. Problems will inevitably arise at some point during the process, especially as Uranium hexafluoride is a highly corrosive material, whose properties where not well understood at the time.
Don't forget too that most gaseous diffusion plants today are only enriching urnaium to reach a 4% to 5% content of U235, which is sufficient for thermal nuclear reactors but not enough for a nuclear weapon.

It is also worth noting that gaseous diffusion requires a lot of energy, where will the energy come from in the context of a war economy where coal and electricity are rationned?

While I would not say that it would have been impossible for a combined British-Commonwealth effort to bear fruits, doing so would have been costly and meant that other parts of the war effort would have been affected.

The best bet is for a small scale independent programme to carry on during the war, looking at gaseous diffusion and building a small nuclear pile in Britain and in Canada. This would make Britain a nuclear power by 1947/8 instead of 1952 OTL.

 

[wiking85]

https://en.wikipedia.org/wiki/Pound_sterling#Use_in_the_Empire
During WW2 the dollar was pegged to the pound at $4.03:1
The Lancaster bomber cost about 45-50,000 pounds, or about $200,000 in WW2 dollars. There were 7,377 built in WW2.
https://en.wikipedia.org/wiki/Avro_Lancaster
That's about $1.4 Billion. The Manhattan Project cost almost $2 Billion in WW2 dollars. So for Britain going for the A-bomb they would have to sacrifice all of their Lancasters and part of the rest of the strategic bombers (the Halifax cost about 42,000 pounds).
Manhattan Project - Wikipedia, the free encyclopedia

The Manhattan Project began modestly in 1939, but grew to employ more than 130,000 people and cost nearly US$2 billion (about $26 billion in 2014[1] dollars). Over 90% of the cost was for building factories and producing the fissile materials, with less than 10% for development and production of the weapons. Research and production took place at more than 30 sites across the United States, the United Kingdom and Canada.

RCAFson claimed it would have cost 10% of the strategic bomber force for Britain to run the Manhattan Project on their own, but for a similar price they would have lost the majority of their strategic bombers from 1942 on.

http://ses.library.usyd.edu.au/bitstream/2123/664/2/adt-NU20050104.11440202whole.pdf

Just some context.

 

[Garyt]

The Manhattan Project began modestly in 1939, but grew to employ more than 130,000 people and cost nearly US$2 billion (about $26 billion in 2014[1] dollars). Over 90% of the cost was for building factories and producing the fissile materials, with less than 10% for development and production of the weapons. Research and production took place at more than 30 sites across the United States, the United Kingdom and Canada.

The cost for technology R+D is amazing. I never thought it was this costly. No wonder the US was the lead country for the atomic bomb - they were the only country that could had the resources to spend this kind of money for resources while fighting a war.

Though it helped a lot that they were not fighting a war where the battlefield was their own country - enemy bombing or the takeover/moving of research installations would have certainly caused delays in the end result.

 

[thedab]

How well would the Germans have done in the med,in 42 with out the Americans leaking information like a sieve.

 

[wiking85]

How well would the Germans have done in the med,in 42 with out the Americans leaking information like a sieve.

https://en.wikipedia.org/wiki/Erwin_Rommel#Role_of_Intelligence_Intercepts_in_North_Africa

The Axis had considerable success in intelligence gathering through radio communication intercepts and monitoring unit radio traffic. The most important success came through Colonel Bonner Fellers, the U.S. military attaché in Egypt. He had been tasked by General George Marshall to provide detailed reports on the military situation in Africa.[117] Fellers talked with British military and civilian headquarters personnel, read documents and visited the battlefront. Known to the Germans as "die gute Quelle" (translated as "the good source") or with a joking play on his name as "der kleine Kerl" ("the little fellow"), he transmitted his reports back to Washington using the "Black Code" of the U.S. State Department. In September 1941 Italian agents had stolen a code book from the US embassy in Rome, photographed and returned it without being detected.[118] The Italians shared parts of their intercepts with their German allies. The "Chiffrierabteilung" (German military cipher branch) were soon able to break the code themselves. Fellers' reports were excessively detailed and played a significant role in informing the Germans of allied strength and intentions.
In addition, the Afrika Korps had the intelligence services of the 621st Signals Battalion commanded by Hauptmann Alfred Seeböhm. The 621st Signals Battalion was a mobile monitoring intelligence unit which arrived in North Africa in late April 1941.[119] It monitored radio communications among British units.[117] Unfortunately for the Allies, the British not only failed to change their codes with any frequency, they were also prone to poor radio discipline in combat. Their officers made frequent open, uncoded transmissions of encouragement to their commands as they went into battle, allowing the Germans to more easily identify British units and deployments.[117] With these Seeböhm had painstakingly compiled code-books and enemy orders of battle. The situation changed after a raid in force by the Australian 2/24th Infantry Battalion resulted in the 621st Signals Battalion being overrun and destroyed, and a significant number of their documents captured, alerting British intelligence to the extent of the problem.[120] The British responded by instituting an improved call signal procedure, introducing radiotelephonic codes, imposing rigid wireless silence on reserve formations, padding out real messages with dummy traffic, tightening up on their radio discipline in combat and creating an entire fake signals network in the southern sector.[120]

No reason it should be too different:
https://en.wikipedia.org/wiki/Bonner_Fellers

In October 1940,[4] Colonel Fellers was assigned as military attaché to the U.S. embassy in Egypt. He was tasked with the duty of monitoring and reporting on British military operations in the Mediterranean and Middle East Theatre. The British granted Fellers access to their activities and information. Fellers dutifully reported everything he learned to his superiors in the United States. His reports were read by President Roosevelt, the head of American intelligence, and the Joint Chiefs of Staff. Unbeknown to Fellers, Axis intelligence read the reports: within eight hours the most secret data on British "strengths, positions, losses, reinforcements, supply, situation, plans, morale etc" were under the gimlet eyes of Adolf Hitler, Benito Mussolini, and Field Marshal Erwin Rommel.[5]
Fellers' concerns about security were overridden and he sent his reports by radio, encrypted in the "Black Code" of the U.S. State Department. Unbeknownst to the U.S. government, the details of this code were stolen from the U.S. embassy in Italy by Italian spies in September 1941. Around the same time it was also broken by German cryptanalysts.[6] Beginning in mid-December 1941 (coincidentally as the U.S. was entering the war) Germany was able to identify Fellers' reports. This lasted until June 29, 1942, when Fellers switched to a newly adopted U.S. code system.[7]

He was getting all that information prior to the US being in the war, so even if they don't enter in 1942 then the British would keep up with the reports with the hope of the US getting involved at some point, but also to help coordinate that theater with other joint theaters.

 

[thedab]

all of rommel big victory's are from Dec41 to june 42 in the time of the American leek. Coincidence?

Rommel didn't do that much in 41,saying how thin Commonwealth forces were in the western desert in 41

and in 41 Commonwealth forces won two campaigns
East African Campaign (World War II) - Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/Syria-
Lebanon_campaign

 

[wiking85]

all of rommel big victory's are from Dec41 to june 42 in the time of the American leek. Coincidence?

Rommel didn't do that much in 41,saying how thin Commonwealth forces were in the western desert in 41

and in 41 Commonwealth forces won two campaigns
East African Campaign (World War II) - Wikipedia, the free encyclopedia
http://en.wikipedia.org/wiki/Syria-
Lebanon_campaign

I get your point, but can you demonstrate that without the US in the war that that leak still wouldn't continue? The Italians got the codes in September 1941 and shared it with the Germans in December. The US officer making the reports was getting full updates and filling reports since 1940 without issue, the US DoW did nothing to change the info that was released via that code. All that changed was Rommel getting access to the information about the time that the US entered the war; without US entry Fellers would still be getting all that British info and filling reports on it, as he had since the start of the Italian invasion in 1940.

As I posted above:
https://en.wikipedia.org/wiki/Bonner_Fellers

In October 1940,[4] Colonel Fellers was assigned as military attaché to the U.S. embassy in Egypt. He was tasked with the duty of monitoring and reporting on British military operations in the Mediterranean and Middle East Theatre. The British granted Fellers access to their activities and information. Fellers dutifully reported everything he learned to his superiors in the United States. His reports were read by President Roosevelt, the head of American intelligence, and the Joint Chiefs of Staff. Unbeknown to Fellers, Axis intelligence read the reports: within eight hours the most secret data on British "strengths, positions, losses, reinforcements, supply, situation, plans, morale etc" were under the gimlet eyes of Adolf Hitler, Benito Mussolini, and Field Marshal Erwin Rommel.[5]
Fellers' concerns about security were overridden and he sent his reports by radio, encrypted in the "Black Code" of the U.S. State Department. Unbeknownst to the U.S. government, the details of this code were stolen from the U.S. embassy in Italy by Italian spies in September 1941. Around the same time it was also broken by German cryptanalysts.[6] Beginning in mid-December 1941 (coincidentally as the U.S. was entering the war) Germany was able to identify Fellers' reports. This lasted until June 29, 1942, when Fellers switched to a newly adopted U.S. code system.[7]

Plus nothing changes about his access to signals intelligence via the 621st Signals Battalion. Perhaps they might even make it past July 1942 without the US in the war due to variables created by US neutrality?

 

[Juha]

https://en.wikipedia.org/wiki/B-24_Liberator#Specifications_.28B-24J.29

Starting when? It was tried from China, but the results were underwhelming. Until Okinawa falls the B-24 cannot raid Japan and then it has a fraction of the payload at that range of the B-29 and much less defensive armament, so would be very vulnerable; for night attacks it lacks the excess fuel capacity to give it the reserve capacity to make it home in case of navigational errors. Plus how much extra would the radar navigation weight? If they're lucky they could manage 1000kg during daylight or less like Operation Tidewave, which would be insanely vulnerable to Japanese fighter defenses. They could raid Kyushu fine from Okinawa (B-17s too), but going after mainland Japan is too far, even for P-38 escorts.

Air raids on Japan - Wikipedia, the free encyclopedia
Historically they didn't really start until 1944 when the B-29 came online, except for minor raids like the Dolittle one.

I bet that Wiki ranges are in fact radii of action (incl. safety reserves). My figure is the distance the plane can fly in one direction. Iwo is 1200km/750mls S of Tokyo. B-24s can bomb Tokyo during darkness but arrive back at Iwo in daylight.

 

[wiking85]

I bet that Wiki ranges are in fact radii of action (incl. safety reserves). My figure is the distance the plane can fly in one direction. Iwo is 1200km/750mls S of Tokyo. B-24s can bomb Tokyo during darkness but arrive back at Iwo in daylight.

Sure, but your figure includes very different payloads at that range. Also 750 miles is a straight line and assuming no wind resistance, plus includes using a lower altitude with about 1000kg of bombs to maintain a safe reserve, especially if operating at night and thus using H2X. How many B-24s would be needed to equal one B-29? How many bombers could be stationed on Iwo? Can Iwo be captured any earlier than early/mid-1944?

 

[Juha]

The end run around AA defenses was a added benefit, the primary reason for air launching was the loss of the in range launch sites. Planning for such a possibility led to the development of air launches. And it (british AA) may have been more effective than the Germans anticipated, but it was by no means anything close to a sure fire defense. Even in Mid-Late 1944, when the defenses were at their zenith, about 30% would still make it thru.

As I wrote earlier, first V-1/He 111 attack happened on 7.July 44. The Allies were still inching through Bogage. And at the beginning of August 44 80% of V-1s were destroyed, that means that 20% not 30% got through.

Exactly. The Capitulation of Okinawa and Iwo Jima was not going to bring Japanese surrender. Perhaps over a long haul, a "siege" of Japan might have brought about their surrender - an Embargo of everything plus constant air attacks over Japan, from B-29's to carrier based fighter bomber strikes. But this would have taken a lot of time, months at least.

Of course, that was what happened historitically, also BBs bombarded industrial targets in Japan before A-bomb attacks.Japanese were ready to peace negoations in summer 44 but were not ready to unconditional surrender before A-bomb attacks and the SU attack into Mantsuria.

 

[thedab]

and one more thing, how well did the 621st battalion do? as it look like they not as good as that bit on wiki make them out be

http://http://www.armchairgeneral.com/radio-kills-rommels-621st-radio-intercept-company.htm
they were good but not that good

 

[Juha]

Sure, but your figure includes very different payloads at that range. Also 750 miles is a straight line and assuming no wind resistance, plus includes using a lower altitude with about 1000kg of bombs to maintain a safe reserve, especially if operating at night and thus using H2X. How many B-24s would be needed to equal one B-29? How many bombers could be stationed on Iwo? Can Iwo be captured any earlier than early/mid-1944?

No, the same 5000lb bomb load but right conversation to kilos, look the Wiki long range figure. 800mls is probably the USAAF radius of action figure for operational planning. So Tokyo and back was possible with adeguate reserve and with 5000lb bomb load, it was tight but possible.
At least 2 B-24s per one B-29 and still smaller bomb carrying capacity and maybe some targets out of range but the RAF Liberator GR III had a max range of 4600mls/7403km, most probably without any offensive load but radar dome or Leight light instead of the ball turret. At low level night attack that was probably ok after all many B-29s had only the tail turret installed when they switched to the low level night attack tactics IIRC.

 

[wiking85]

No, the same 5000lb bomb load but right conversation to kilos, look the Wiki long range figure. 800mls is probably the USAAF radius of action figure for operational planning. So Tokyo and back was possible with adeguate reserve and with 5000lb bomb load, it was tight but possible.
At least 2 B-24s per one B-29 and still smaller bomb carrying capacity and maybe some targets out of range but the RAF Liberator GR III had a max range of 4600mls/7403km, most probably without any offensive load but radar dome or Leight light instead of the ball turret. At low level night attack that was probably ok after all many B-29s had only the tail turret installed when they switched to the low level night attack tactics IIRC.

Too tight for comfort, which not something that air forces were willing to risk; night time missions were totally different animal too, as they required extra fuel for navigation challenges that didn't exist during the day.

 

[Garyt]

As I wrote earlier, first V-1/He 111 attack happened on 7.July 44. The Allies were still inching through Bogage.

Just because the first airborne launch happened while the installations had not yet been overrun a month after D-day does not mean that the Germans were not looking at the possible or even probable eventuality of having these launch sites compromised.

Heck, this was a month after Normandy and the Allies had a very secure beachhead.

I think they were planning and testing with this eventuality very much in their thoughts.

 

[Juha]

War is risky business as seen e.g. during the P-51 escort missions from Iwo to Japan.