The Lancaster as a potential nuclear bomber in 1945

[nuuumannn]

Yes, just watched this. I'd never heard of this 'Black Lancaster Squadron' before and Felton's claim that no official documents exist that mentions them would make it very difficult to find out information, which would be very welcome. Felton does get a few things wrong in this. He does not mention Thin Man, the first aerial atom bomb project, which is why Ramsay suggested the Lancaster as the only bomber that could carry the bomb internally without modification. Then Felton then goes on to incorrectly state that the B-29 could not carry Little Boy and Fat Man internally without modification to its bomb bays. Thin Man was of course 17 feet long, which required a single B-29 to be modified to carry it internally, which Felton references, but Little Boy and Fat Man could fit within the B-29's bomb bay without altering it.

He also mentions that the Lancaster could carry Fat Man, but it was too wide and would require removal of its bomb doors, to say nothing of the drag factor of having it hanging under the aircraft. Little Boy would have been a cinch to carry internally by the Lancaster as we have discussed however, but by the time Thin Man was abandoned and Little Boy was being developed the Americans had ruled out the use of the Lancaster, which Felton acknowledges in his video.

His estimation of the Lancaster's range is also something of a stretch taking into consideration its warload, fuel load and performance figures. To achieve a range of over 2,000 miles as Felton states, the Lanc would have had to reduce its warload and quite probably its performance. As we've discussed here before, if you alter one factor, like increasing range, something has to give, like payload. A bigger payload means less range etc.

Would love to know more about this Black Lancaster Squadron. Sadly, Felton's video provides little more than the base and a number of aircraft...

 

[FLYBOYJ]

On topic:

Good clip but "What if?" "Could have, would have, should have." Many of his points were dismissed in this thread.

 

[nuuumannn]

Lordy :rollseyes: thought I'd continue this here since it is more appropriate.

Dr Norman Ramsey was the man tasked with designing the atomic bomb casings and in finding a suitable aircraft for testing and actual delivery. It is very clear from the historical record that Ramsey favoured the Lancaster, and that his research led him to conclude that only two Allied bombers were suitable to carry the proposed weapons, the B-29 and the Lancaster. Ramsey conferred with Roy Chadwick, the designer of the Lancaster and showed him drawings of the proposed bomb casings including FAT MAN, the implosion bomb, and was assured by Chadwick that the Lancaster could accommodate either bomb design:

"The person at Los Alamos with who, Wilson primarily worked was Norman F. Ramsey.
Ramsey, son of an army officer, received a Ph.D. in physics from Columbia in 1939, and
was drafted to work at the MTT Radiation Lab the following year."" After some time in
Cambridge he came to Washington to work in Stimson's office on Army Alr Forces
projects for Edward Lindley Bowles, a consultant to the secretary. Ramsey's combination of
expertise in physics and aerodynamics made him a prime candidate for Los Alamos. After
an effective recruitment appeal by Oppenheimer in March 1943, Ramsey agreed to foin the
project. Oppenheimer left t to Groves o get Stimson to agree to release Ramsey. This took
several months, because Bowles refused to let him go. Bowles and Groves were both used to
getting their way, and who would get Ramsey turned into a matter of prestige and power.
To men in powerful positions losing a bureaucratic battle, even a small one, could mean
Losing others in the future, and that must not be allowed to happen. Rather than push it to
the hilt, Bowles found a way out by asking Ramsey what he wanted to do. Ramsey said he
thought he should go to Los Alamos. To allow Bowles to save face Ramsey continued as a
consultant from the secretary of war's offce and was not an employee of the University of
California, Los Alamos's contractor.

Ramsey was assigned to head the Delivery Group of the Ordnance Division and later
served as deputy to Pasion." His immediate tasks were to design the bomb casings that
would carry the gun-assembly bomb and implosion bomb. By the end of 1943 it had
already been established that the gun-type bomb-Thin Man-would weigh on the order
of five tons. Ramsey assumed that the implosion bomb would weigh approximately the
same. Given their size and weight, there were only two possible choices for an aircraft to
deliver the weapons, the British Lancaster or the American B-29, which had begun
production in September.

Ramsey favored the Lancaster and traveled to Canada in early October 1943 to meet Roy
Chadwick, the plane's chief designer, Chadwick was in Canada to observe the initial
Lancasters coming off the production line at the Victory Aircraft Works, Milton Airdrome,
in Toronto. Ramsey showed Chadwick preliminary sketches of the large-thin-shaped and
stubby shaped-bombs and later wrote with more details.(12) Chadwick assured Ramsey that
the Lencaster could accommodate them.

When Ramsey returned, he wrote to Parsons suggesting that the Lancaster be seriously
considered and planned a memo to General Groves recommending that a modified
Lancaster be used.(13)The bomb bay was thirty-three feet long and sixty-one inches wide.
The depth was only thirty-eight inches, but this could be modified. The Lancaster's ceiling
was 27,000 feet, its speed 285 miles per hour, and takeoff required only 3,750 feet of runway
-a critical matter wherever it would be based.

Groves had not been Informed about Ramsey's preference and was at a loss for words
when he found out. It was beyond comprehension that Ramsey could consider using a
British plane to deliver an American atomic bomb. Needless to say, Groves found an ally in
General Arnold when he discussed. this matter with him. The new Boeing B29
Superfortress would carry the atomic bomb.

The first production B-29s were produced at the Boeing-Wichita plant beginning in
September 1943. One was chosen to be modified; by December 1 it was at Wright Feld for
two months of modifications. The modifications were originally called Silver Plated. but
this was soon shortened to Siverplate. On the same day General Arnold's office informed
the commanding general, Material Command, that Siverplate modifications should be
given "the greatest possible priority." The two bomb bays were made into one, and the four
twelve-foot bomb bay doors were replaced by two. twenty-seven-foot pneumatically
operated doors. At this point the length of the Thin Man bomb was expected to be at least
seventeen feet. Racks, bracing, and hoists were installed, long with the release mechanism
and mounts for a motion picture camera to record training drops.

On February 20, 1944, the first hand-modified Silverplate B-29 flew from Wright Fld to
Muros Army Air Base (now Edwards AFB) in the Mojave Desert of California. Drop tests
of the Thin Man and Fat Man dummy bombs began on March ."" Many problems were
encountered and corrected, The ballistics for the Thin Man had been partially worked out
at Dahlgren, where scale-model tests were conducted. The bulbous Fat Man shape was
another matter it proved more difficult over the next year to find the correct tall structure
design to prevent it from wobbling. As the analysts sought their solution, they made
another discovery The standard tailfins used on air force aerial bombs seemed to have a
flaw, which caused some of the fins to collapse as the bomb reached terminal velocity. This
had an obvious effect on accuracy and would have been of great interest to the Ordnance
Department. But when this information was passed on to Groves he suppressed it, not
wanting to compromise security It took another year for the Ordnance Department to find
out.

As the tests continued, further modifications and refinements were made to the aircraft
to arrive at a final standard. These mainly had to do with the bomb bay and the various
frames, hoists, braces, and release assemblies that could handle the four-and five-ton
bombs. One major change was to adopt a single lug to suspend the heavy bomb rather than
twin release lugs, which had caused problems. Once premature release of a seventy-three
hundred-pound Thin Man caused severe damage to the bomb bay doors of the single B-29
in March. After repairs were made, testing resumed in mid-June.

By the summer of 1944 the design was fairly firm, and on August 23 the Glenn L. Martin
-Nebraska Company received the contract to modify the first three B-29s of a total of
twenty-four-and selected its Fort Crook Modification Center in Omaha as the program
site. The delivery schedule was three planes by the end of September, the next eleven by
the end of the year, and the final en in January 1945, The initial fourteen were slated for
test and training, with the other ten assigned as the combat unit. As with most parts of the
Manhattan Project, schedules were accelerated and quantities increased. In February the
number of Silverplate B-29s was increased to forty-eight, and on April 18 to fifty-three-
fifty-four counting the hand-modified Muroc plane. As Los Alamos continued to change
and refine its design for the bombs, new instructions were repeatedly sent to modify the
bombers. By the end of the war forty-six planes had been completed.

(12). Norman F, Ramsey Jr. to Roy Chadwick, October 23, 1943, Folder Dr. Norman Ramsey, Box 6,
Tolman Files, RG 227/81, NARA.

(13). Memo, N. F, Ramsey to Capt. W. . Parsons, October 14, 1943, Lancaster Aircraft, Folder Dr Norman Ramsey... NARA
" (Norris, pages 316-317 Racing for the Bomb)

Yes, I have read these sources and have even referenced these highlighted sections in brief in my article, but it in no way changes my statement that the Americans never seriously considered the Lancaster for carrying the Little Boy or Fat Man bombs operationally. Within the passages is the following:

"Groves had not been Informed about Ramsey's preference and was at a loss for words
when he found out. It was beyond comprehension that Ramsey could consider using a
British plane to deliver an American atomic bomb. Needless to say, Groves found an ally in
General Arnold when he discussed this matter with him. The new Boeing B29
Superfortress would carry the atomic bomb."

This is after this:

"When Ramsey returned, he wrote to Parsons suggesting that the Lancaster be seriously
considered and planned a memo to General Groves recommending that a modified
Lancaster be used.(13)"

So, we know that Ramsey wanted the Lancaster to be seriously considered, because it was not being so at the time, otherwise, why would he suggest something that was already happening?

Next, Groves, in charge of the Manhattan Project states that he was at a loss for words when he found out about Ramsey's suggestion, which means that this is the first he is hearing of it. If the Lancaster was being seriously considered, why would he react that way?

The final nail in the coffin is the last two sentences, which state that Groves found an ally in Arnold, which means he was obviously opposed to the idea and that the B-29 was to be the atom bomber. The term beyond comprehension reflects his attitude toward the suggestion.

This ties in neatly with Ramsey's own subsequent official report on the situation and he apparently agreed, emphasising that the Lancaster was to be used for trials only, while the B-29 would be the operational platform. Taken from a report that Ramsey wrote on 27 September 1945 to Brig Gen T.F. Farrell, within which is a history of Project A:

"In view of the critical shortage of B-29's it was at first proposed that a British Lancaster be used for the test work even though a B-29 would almost certainly be used as the combat ship."

Finally, we see that even Ramsey had changed his mind about the use of the Lancaster, indicating that the decision not to use it for testing was the right one, as follows:

"The Air Forces, however, wisely recommended that a B-29 be used for the test work as well, both to avoid non-standard maintenance and to accumulate experience in B-29 operations with such a bomb."

All this does is reinforce what I have maintained all along, that the Lancaster was only ever suggested in letters and conversation, with Ramsey as its biggest supporter and the origin of the suggestion, and even then he later demonstrably changed his stance on the matter in official sources. The theory that it was "seriously considered" just doesn't hold water, not when the head of the Manhattan Project and the Chief of the USAAF both rejected it outright.

 

[RCAFson]

Lordy :rollseyes: thought I'd continue this here since it is more appropriate.



Yes, I have read these sources and have even referenced these highlighted sections in brief in my article, but it in no way changes my statement that the Americans never seriously considered the Lancaster for carrying the Little Boy or Fat Man bombs operationally. Within the passages is the following:

"Groves had not been Informed about Ramsey's preference and was at a loss for words
when he found out. It was beyond comprehension that Ramsey could consider using a
British plane to deliver an American atomic bomb. Needless to say, Groves found an ally in
General Arnold when he discussed this matter with him. The new Boeing B29
Superfortress would carry the atomic bomb."

This is after this:

"When Ramsey returned, he wrote to Parsons suggesting that the Lancaster be seriously
considered and planned a memo to General Groves recommending that a modified
Lancaster be used.(13)"

So, we know that Ramsey wanted the Lancaster to be seriously considered, because it was not being so at the time, otherwise, why would he suggest something that was already happening?

Next, Groves, in charge of the Manhattan Project states that he was at a loss for words when he found out about Ramsey's suggestion, which means that this is the first he is hearing of it. If the Lancaster was being seriously considered, why would he react that way?

The final nail in the coffin is the last two sentences, which state that Groves found an ally in Arnold, which means he was obviously opposed to the idea and that the B-29 was to be the atom bomber. The term beyond comprehension reflects his attitude toward the suggestion.

This ties in neatly with Ramsey's own subsequent official report on the situation and he apparently agreed, emphasising that the Lancaster was to be used for trials only, while the B-29 would be the operational platform. Taken from a report that Ramsey wrote on 27 September 1945 to Brig Gen T.F. Farrell, within which is a history of Project A:

"In view of the critical shortage of B-29's it was at first proposed that a British Lancaster be used for the test work even though a B-29 would almost certainly be used as the combat ship."

Finally, we see that even Ramsey had changed his mind about the use of the Lancaster, indicating that the decision not to use it for testing was the right one, as follows:

"The Air Forces, however, wisely recommended that a B-29 be used for the test work as well, both to avoid non-standard maintenance and to accumulate experience in B-29 operations with such a bomb."

All this does is reinforce what I have maintained all along, that the Lancaster was only ever suggested in letters and conversation, with Ramsey as its biggest supporter and the origin of the suggestion, and even then he later demonstrably changed his stance on the matter in official sources. The theory that it was "seriously considered" just doesn't hold water, not when the head of the Manhattan Project and the Chief of the USAAF both rejected it outright.

There was a point in time when the B-29 was not considered either but Ramsey looked carefully at both the Lancaster and B-29 and chose the Lancaster.

Ramsey was in charge of bomb casing design and is tasked with finding a training and delivery aircraft. Ramsey's choice is the Lancaster because it requires fewer mods and is considerably more reliable. The decision to go with the B-29 to the exclusion of the Lancaster didn't happen until 21 March 1944:

The two leaders next took up the
question of what type of airplane
would be required to - transport
atomic bombs. The Manhattan com-
mander noted that Oppenheimer, on
the basis of investigations carried out
at Los Alamos and Muroc Army Air
Field, had concluded that a modified
B-29 probably had the requisite
weight-carrying capacity and range.
Should the B-29, which had gone
into production in September 1943,
prove not feasible, Groves suggested
the British Lancaster would have to
be considered. - This displeased
Arnold, who stated emphatically that
an American-made airplane should
carry the bombs, and he promised to
make a special effort to have a B-29
available for that purpose. (3)
(3) Groves Diary, 21 Mar 44, LRG; H. H. Arnold.
Manhattan - The Army and the Atomic Bomb.

Groves might have been relieved that the USAAF was going to make development of Silverplate B-29s a priority, but it was Groves himself who stated to Arnold that the Lancaster might have to used if the B-29 was found to be unsuitable (mainly because of engine and bomb bay development issues). The fact is that the B-29 had some serious issues and these delayed bomb casing drop testing for some months but because the bomb detonation design itself was not ready there was time for Silverplate to sort out the B-29's reliability. Groves didn't overrule Ramsey rather he went along with Ramsey's choice until he was assured that Silverplate would deliver a reliable aircraft by the time the bomb was operationally ready.

Delays in bomb development gave the B-29 time to sort out it's issues, but if the atomic bomb detonation designs had been developed sooner (and the B-29 wasn't ready to even carry a practice bomb safely until June 1944) , then the Lancaster would have been the logical choice especially as Germany would then be on the target list. Groves would then have been almost forced to go with the Lancaster despite Arnold's objections because they would have been denying the Allied cause access to a reliable nuclear weapon delivery system.

The accidentally parallel development of the fission bomb designs and the B-29 makes it look like the B-29 was the inevitable choice but in fact it was just a coincidence.

 

[RCAFson]

Yes, just watched this. I'd never heard of this 'Black Lancaster Squadron' before and Felton's claim that no official documents exist that mentions them would make it very difficult to find out information, which would be very welcome. Felton does get a few things wrong in this. He does not mention Thin Man, the first aerial atom bomb project, which is why Ramsay suggested the Lancaster as the only bomber that could carry the bomb internally without modification. Then Felton then goes on to incorrectly state that the B-29 could not carry Little Boy and Fat Man internally without modification to its bomb bays. Thin Man was of course 17 feet long, which required a single B-29 to be modified to carry it internally, which Felton references, but Little Boy and Fat Man could fit within the B-29's bomb bay without altering it.

He also mentions that the Lancaster could carry Fat Man, but it was too wide and would require removal of its bomb doors, to say nothing of the drag factor of having it hanging under the aircraft. Little Boy would have been a cinch to carry internally by the Lancaster as we have discussed however, but by the time Thin Man was abandoned and Little Boy was being developed the Americans had ruled out the use of the Lancaster, which Felton acknowledges in his video.

His estimation of the Lancaster's range is also something of a stretch taking into consideration its warload, fuel load and performance figures. To achieve a range of over 2,000 miles as Felton states, the Lanc would have had to reduce its warload and quite probably its performance. As we've discussed here before, if you alter one factor, like increasing range, something has to give, like payload. A bigger payload means less range etc.

Would love to know more about this Black Lancaster Squadron. Sadly, Felton's video provides little more than the base and a number of aircraft...

Lancasters attacked Tirpitz with Tallboys whilst operating from Northern Scotland. Total range required was ~2400 miles with the target being 2250 miles from base.

 

[RCAFson]

I don't think that the Lancaster was ever considered to carry Little Boy or Fat Man. Rather it was Thin Man, the first bomb developed, which brought the Lancaster into consideration. Thin Man was very long which meant that it could not fit in a standard B-29 bomb bay.

But a B-29 was modified so that it could carry that bomb, so the Lancaster was no longer considered.

Fat Man and Little Boy could fit inside a modified standard size B-29 bomb bay, so no need to use a Lancaster for them.

The Dr Ramsey, designer of the Fat Man bomb casing, specifically chose the Lancaster because of it's ability to carry that bomb. See this post:

German Aircraft that could deliver The Bomb

and this is well documented via Dr Ramsey's own files. The B-29 had a rather troubled development and it was not apparent, in 1943, that it would be reliable enough to carry any a-bomb design.

 

[nuuumannn]

Should the B-29, which had gone
into production in September 1943,
prove not feasible, Groves suggested
the British Lancaster would have to
be considered. - This displeased
Arnold, who stated emphatically that
an American-made airplane should
carry the bombs, and he promised to
make a special effort to have a B-29
available for that purpose. (3)
(3) Groves Diary, 21 Mar 44, LRG; H. H. Arnold.
Manhattan - The Army and the Atomic Bomb.

So, this is actually contradictory to your previous post then, which clearly states that Groves disapproved of the Lancaster, now you've dug up something else, which says it may have to be considered, but let's note what is actually said, again.

"Should the B-29, which had gone into production in September 1943, prove not feasible, Groves suggested the British Lancaster would have to
be considered."

Groves believes that the Lancaster would need to be considered, not that it is being considered and only if the B-29 doesn't prove feasible, which simply supports my view that it wasn't considered. Also, there is nothing in that sentence that states that Groves actually supports the use of the Lancaster, but that it might need to be considered - not that it actually is being considered - but again, Arnold says no.

Again, letters and discussions, nothing more.

Keep them coming; soon you are going to run out of sources that continually prove my point instead of your own.

 

[SaparotRob]

The B-32 was the backup plan. I imagine if both B-29 and the B-32 failed the Lancaster would have been considered. The Superfortress and the Dominator were both going through development issues IIRC initially. The Lancaster was a known asset.

 

[nuuumannn]

I imagine if both B-29 and the B-32 failed the Lancaster would have been considered. The Superfortress and the Dominator were both going through development issues IIRC initially. The Lancaster was a known asset.

Undeniably, as we can see by what's being posted here, it was certainly discussed by Ramsey and Groves. How the deficiencies in performance were going to be catered for remains an open question for the fantasists since it never got that far and it was never seriously investigated. It remains a tantalising what-if, but with so many caveats.

 

[RCAFson]

Undeniably, as we can see by what's being posted here, it was certainly discussed by Ramsey and Groves. How the deficiencies in performance were going to be catered for remains an open question for the fantasists since it never got that far and it was never seriously investigated. It remains a tantalising what-if, but with so many caveats.

"...never seriously investigated..." We have the Los Alamos bomb casing designer, Dr Ramsey, personally conferring with the Lancaster designer, Roy Chadwick, who together decide that the Lancaster can do the job and telling Grove that, who in turn tells Arnold. How much more serious can you get? The Lancaster is already proving in combat that it can carry bombs heavier than any of the A-bomb designs and the Lancaster bomb suspension and release system was in fact fitted to Silverplate B-29s. The only thing that prevented the Lancaster being used for A-bomb training and operational use was delays in A-bomb development.

The fact is that the historical record shows that the Lancaster was chosen in 1943 as more suitable for A-bomb delivery by the A-bomb's bomb casing designer. Delays in A-bomb development allowed the B-29 to reach sufficient maturity via Silverplate to replace the Lancaster as the aircraft of choice.

 

[RCAFson]

The B-32 was the backup plan. I imagine if both B-29 and the B-32 failed the Lancaster would have been considered. The Superfortress and the Dominator were both going through development issues IIRC initially. The Lancaster was a known asset.

The first production B-32 wasn't produced until 19 September 1944 and only a handful were produced by the end of 1944. The B-32 was never in the running.

 

[RCAFson]

So, this is actually contradictory to your previous post then, which clearly states that Groves disapproved of the Lancaster, now you've dug up something else, which says it may have to be considered, but let's note what is actually said, again.

"Should the B-29, which had gone into production in September 1943, prove not feasible, Groves suggested the British Lancaster would have to
be considered."

Groves believes that the Lancaster would need to be considered, not that it is being considered and only if the B-29 doesn't prove feasible, which simply supports my view that it wasn't considered. Also, there is nothing in that sentence that states that Groves actually supports the use of the Lancaster, but that it might need to be considered - not that it actually is being considered - but again, Arnold says no.

Again, letters and discussions, nothing more.

Keep them coming; soon you are going to run out of sources that continually prove my point instead of your own.

"Again, letters and discussions, nothing more." Which is the process that occurs when decisions are being made. The Lancaster was chosen by Ramsey. This is indisputable.

Groves was an engineer tasked with developing a viable nuclear weapon with a reliable delivery system. What Groves as a US Army officer personally wanted and what he, as an engineer and project manager, would recommend were two different things. Groves told Arnold that the Lancaster was on the table and would remain there unless the USAAF could make the B-29 reliable.

 

[Peter Gunn]

"Again, letters and discussions, nothing more." Which is the process that occurs when decisions are being made. The Lancaster was chosen by Ramsey. This is indisputable.

Groves was an engineer tasked with developing a viable nuclear weapon with a reliable delivery system. What Groves as a US Army officer personally wanted and what he, as an engineer and project manager, would recommend were two different things. Groves told Arnold that the Lancaster was on the table and would remain there unless the USAAF could make the B-29 reliable.

In a total break from convention, I ask without being snarky...

1. What would Ramsey have to do with the delivery aircraft? Wouldn't that choice be made by the U.S.A.A.F.?

2. When/where did Groves tell Arnold that the "Lancaster was on the table..."?

 

[RCAFson]

In a total break from convention, I ask without being snarky...

1. What would Ramsey have to do with the delivery aircraft? Wouldn't that choice be made by the U.S.A.A.F.?

2. When/where did Groves tell Arnold that the "Lancaster was on the table..."?

(1)Dr Ramsey's job at Los Alamos was to design the bomb casings and to select suitable aircraft for training and delivery - this has been explained and documented in prior posts: German Aircraft that could deliver The Bomb

(2)
Should the B-29, which had gone
into production in September 1943,
prove not feasible, Groves suggested
the British Lancaster would have to
be considered. - This displeased
Arnold, who stated emphatically that
an American-made airplane should
carry the bombs, and he promised to
make a special effort to have a B-29
available for that purpose. (3)
(3) Groves Diary, 21 Mar 44, LRG; H. H. Arnold.
Manhattan - The Army and the Atomic Bomb.

Groves was outranked by Arnold, and it appears that he was following military protocol by framing his statement as a "suggestion".

 

[Peter Gunn]

(1)Dr Ramsey's job at Los Alamos was to design the bomb casings and to select suitable aircraft for training and delivery - this has been explained and documented in prior posts: German Aircraft that could deliver The Bomb

(2)
Should the B-29, which had gone
into production in September 1943,
prove not feasible, Groves suggested
the British Lancaster would have to
be considered. - This displeased
Arnold, who stated emphatically that
an American-made airplane should
carry the bombs, and he promised to
make a special effort to have a B-29
available for that purpose. (3)
(3) Groves Diary, 21 Mar 44, LRG; H. H. Arnold.
Manhattan - The Army and the Atomic Bomb.

Groves was outranked by Arnold, and it appears that he was following military protocol by framing his statement as a "suggestion".

Mmm... I don't know, I see that as Groves suggesting that the Lancaster would have to be considered, meaning to me, they were not considering it and may not have any intent to do so unless the B-29 issues reached critical mass. I can see how it might be interpreted that the Lancaster was in the running, but I don't feel anything concrete was really done about it, just my way of looking at it at present, I'm always ready to reevaluate with the proper evidence though.

Thanks for the response.

 

[RCAFson]

Mmm... I don't know, I see that as Groves suggesting that the Lancaster would have to be considered, meaning to me, they were not considering it and may not have any intent to do so unless the B-29 issues reached critical mass. I can see how it might be interpreted that the Lancaster was in the running, but I don't feel anything concrete was really done about it, just my way of looking at it at present, I'm always ready to reevaluate with the proper evidence though.

Thanks for the response.

Considered = chosen as the training and delivery aircraft. Ramsey, whose job it was, had already considered it and stated that it was his preferred aircraft, over the B-29, in late 1943.

The Lancaster was in the running because Ramsey states that unequivocally; this is indisputable. Groves states that it was the alternative to the B-29 so by definition if the B-29 proved to be unsuitable, for whatever reason, then the Lancaster was the only alternative. The Lancaster was able to accept any A-bomb design with really minimal mods so there's no need to acquire any Lancasters for development. Delays in the bomb program itself never forced Groves' hand. This is from Groves himself:

Page 244, NOW IT CAN BE TOLD

the implosion bomb, although we were quite certain of these factors
for the gun type. However, after discussing this problem with Oppen-
heimer and his senior associates at Los Alamos, I had decided it
would be reasonable to plan on using the B-29 as the carrier plane
for both types, though we might have to make certain modifications,
all of which appeared feasible, in the plane's bomb bay and bomb-
handling equipment, Nevertheless, we all recognized that problems
then unforeseen might make the use of the B-29 impossible.

When I told Arnold there was a chance that we might not be
able to fit the bomb into the B-29, no matter how hard we tried, he
asked me what I would do then. I said that if the B-29 could not
be used, we would have to consider the use of a British plane, the
Lancaster, which I was sure the Prime Minister would be glad to
make available to us.

This brought from him the characteristic reply that I had hoped
and expected to bear: that he wanted an American plane to deliver
our bomb, and that the Air Force would make every effort to ensure
that we had a B-29 capable of doing the job. Because the use of
a British plane would have caused us many difficulties and delays,
I, too, was most anxious to use the B-29 if it could be done.
Fortunately, as time went on, we were able to make changes in the
design of both types of bombs, so that it became possible to fit them
into a specially modified B-29.

Engine issues, for example, might have ruled out the B-29.

I don't quite understand why the logic of the situation, then, meets so much resistance today. Had the A-bomb been ready before the B-29, it's pretty obvious which Allied aircraft would have been chosen to deliver it, especially as the target would have been Germany.

 

[RCAFson]

Since this thread has been revived, here's some info from Groves on aircraft safety due to a-bomb blast:


To be well removed from the point of burst, the bombing plane
would have to maneuver as no heavy bomber had ever had to maneuver
before. As soon as the bomb was "away," the plane was to make a
sharp diving turn to get as far as possible from the point of explosion.
This was one of the reasons why the run was made at the then un-
precedented altitude of some thirty thousand feet. The high altitude
also greatly reduced the danger of gunfire from enemy airplanes, per-
mitting the removal of the fuselage turrets and all other armament
except for the tail guns. This weight reduction appreciably increased
the plane's range and the height at which it could fly.
Studies made at Los Alamos had determined that with a bomb of
twenty thousand tons of TNT equivalent, a B-29 plane ten miles away
from the burst would be safe from destruction by a factor of two.
Under these conditions, the aircraft, which had been designed to with-
stand a force of four times gravity, would be subjected to a force
equivalent to no more than two times gravity. It was calculated that by
making a sharp diving turn, the sharpest possible consistent with safety,
the B-29 could reach a point at least ten miles from the burst by the
time the bomb exploded.

So we can see that a large safety margin had been built into the calculation, and even a Merlin 24 engined Lancaster could have dropped the bomb with a considerable safety margin, although my druthers would have been for a Merlin 85 engined Lancaster VI.

 

[Koopernic]

The first production B-32 wasn't produced until 19 September 1944 and only a handful were produced by the end of 1944. The B-32 was never in the running.

The Hiroshima and Nagasaki attacks occurred on August 6 and 9, 1945, respectively, so there is 11 months for the production B-32 to be made operationally ready The CW R-3350 engine was the biggest risk to the plans for an atomic carrier, not the airframe, whether B-29 and B-32 program however the Allison V-3420 seems to have been a satisfactory backup that could have powered either aircraft type reliably.

 

[RCAFson]

The Hiroshima and Nagasaki attacks occurred on August 6 and 9, 1945, respectively, so there is 11 months for the production B-32 to be made reliable. The CW R-3350 was the biggest risk to the B-29 and B-32 program however the Allison V-3420 seems to have been a satisfactory backup that could have powered either aircraft type reliably.

IIRC, there were more Silverplate B-29's built up to Aug 1945 than all combat variants of the B-32 combined. The first production B-32 wasn't delivered until 19 Sept 1944 (Groves was telling Arnold in late March 1944 that they'd have to go with the Lancaster if the B-29 wasn't made reliable) and promptly crashed on it's delivery flight.

 

[nuuumannn]

The fact is that the historical record shows that the Lancaster was chosen in 1943 as more suitable for A-bomb delivery by the A-bomb's bomb casing designer.

Funny how you choose to interpret what's in front of you. The Lancaster was not chosen by anyone. This has been pointed out to you in virtually every post you have replied with. Ramsay recommended the Lancaster, discussed it with Groves who ultimately rejected it along with Arnold, who had the final say in terms of delivery system, so no, you are once again wrong in interpreting the facts that you are presenting.

The final say as to which delivery system is NOT Ramsey, it is ARNOLD, which means that the Lancaster WAS NEVER SERIOUSLY CONSIDERED, since Arnold said NO! Which part of that do you not understand?

The Lancaster was chosen by Ramsey. This is indisputable.

Ramsey did not choose the Lancaster. He recommended it. The Lancaster was not considered by anyone else. The ultimate decision was Arnold's AND HE SAID NO!

Read your source material RCAFson. Posting the same stuff over and over doesn't change anything. The facts still remain that the Lancaster was not seriously considered for delivery of the nuclear bombs. Ramsey's report, which I have posted in his words more than twice on this forum confirms this, as do Groves' and Arnold's, the three people at the centre of this debate.