The Lancaster as a potential nuclear bomber in 1945 (1 Viewer)

[nuuumannn]

The fact that Arnold wanted an American delivery system is not in doubt, why is the interesting point. Arnold was heavily invested in the B-29 and determined to make it work, for good reason, it was very advanced and offered performance unmatched by any other heavy bomber in service at the time. I don't know what Arnold had in mind as an alternative, but I'm willing to bet that Arnold believed that the B-29 was the only answer, despite its various issues. I'm also willing to bet that regardless of the seriousness of the issues that arose with the B-29 that he was prepared to keep throwing money and resources at it until it was able to do the mission. That it succeeded and carried out the mission using parameters that no other bomber could have flown at the time was evidence that Arnold back the right horse.

 

[nuuumannn]

RCAFson, here is a suggestion for you. Since you are expending sooooo much time trying to prove your point, why don't you put it to good use? Gather all the evidence you have, get hold of some images, write a thesis or an article about why you believe what you do and cite your sources and get it published. Put your money where your mouth is and do this in the public interest instead of doing it just to prove a point on this forum.

If you are so utterly convinced you are right, do something about it. Be careful though, your arguments are being discredited here (quite easily so because you are misinterpreting your selling points), so it might not work out in your favour. Think about what it is that is motivating you to continually repeat the same thing over and over again and if you still feel it is worth pursuing, do it.

 

[FLYBOYJ]

"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."


"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.


The answer is in your own post!

"Would have, could have, should have."

Now shall we compare that Merlin 85 engined Lancaster VI to the B-29D (B-50)?

 

[Graeme]

The thread title is discussed in the August issue of "Aeroplane"....

 

[RCAFson]

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?



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.

I walk into a bar and am offered several brands of beer and narrow the choice to two different brands. I examine the bottles, read the labels, ask around for opinions, call the brewmasters for detailed info on the brewing process, and then make my selection....according to you I never seriously considered the losing brand!

The future is unknowable. In 1943 Ramsey picked the Lancaster as the preferred aircraft. On 22 March 1944, Groves is backing Ramsey and tells Arnold that if the B-29 doesn't come up to acceptable standards, then the Lancaster is the backup plan. This is clear. The fact that the B-29 was made into an acceptable delivery system doesn't mean that the Lancaster wasn't seriously considered; It was and both Ramsey and Groves state that it was.

It wasn't actually up to Arnold to decide which aircraft would be chosen, but obviously it was desirable that Arnold would be in agreement and provide the needed aircraft and support without Groves having to go around/over him. However, if the B-29's teething troubles and Silverplate conversion process proved to be insurmountable then no matter what Groves might have personally wanted, or what Arnold preferred, the Lancaster was the only alternate to the B-29. This is indisputable. To say that the Lancaster wasn't seriously considered is just plain wrong.

 

[RCAFson]

"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."


"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.


The answer is in your own post!

"Would have, could have, should have."

Now shall we compare that Merlin 85 engined Lancaster VI to the B-29D (B-50)?

What would have happened if the B-29 could not be used? Was the Manhattan project going to be halted? Would the A-bombs be built but put into storage? Or would Groves have picked up the phone and asked Churchill for some reverse lend-lease Lancasters?

Because Ramsey's suggestion to acquire Lancasters in 1943 wasn't acted upon, yes acquiring them in mid 1944 would have caused delays, but surely no more than happened with the B-29.

The Lancaster VI flew in mid (June, IIRC) 1943. The XB-44 (B-50 prototype) didn't fly until May 1945. You may be thinking of the Lancaster IV (Lincoln prototype) which flew in June 1944.

 

[RCAFson]

The thread title is discussed in the August issue of "Aeroplane"....

View attachment 599126

The article has a few flaws.

It states that the Fatman would not fit into a Lancaster bomb bay without removing the doors, but the maximum width was short enough to have allowed for bulged doors to be fitted. Yes, there would have been some extra drag, but probably little more than that already produced by the radome and would have been largely offset by removal of the mid upper and front turrets.

A major flaw is in the range calculation. The Lancasters that flew the Tirpitz raids from Scotland covered about 2400 miles, and one even managed to fly the mission and return with a hung up bomb and this was achieved by using a 400IG internal Wellington aux tank, for a total of about 2560 IG of internal fuel. By the use of custom internal aux tanks, maximum fuel load of a Lancaster VI, minus the front and upper turrets, whilst carrying a FATMAN would be about 3000IG (with aux tanks fore and aft of the bomb) and a range of ~3000 miles. Like the Silverplate B-29s the mission would use a low-high-low flight profile, so that minimal time is spent at high altitude and initial climb to attack altitude is done with a large amount of fuel (1200-1500IG or ~8600-11000lb) of fuel burned off. However, even this is insufficient range for safe mission planning with a return to Tinian, and so TO from Tinian would involve a mission plan that included landing at Okinawa or Iwo Jima after weapon release.

A 'Silverplate' Lincoln should have been able to fly to and from Tinian with aux bomb bay tanks.

 

[FLYBOYJ]

What would have happened if the B-29 could not be used?

What would have happened if Hitler was killed in WW1?

Because Ramsey's suggestion to acquire Lancasters in 1943 wasn't acted upon, yes acquiring them in mid 1944 would have caused delays, but surely no more than happened with the B-29.

And a suggestion, not a decision by any means....

The Lancaster VI flew in mid (June, IIRC) 1943. The XB-44 (B-50 prototype) didn't fly until May 1945. You may be thinking of the Lancaster IV (Lincoln prototype) which flew in June 1944.

No I'm thinking the XB-44 and using the same wishful thinking you've been using!

 

[Peter Gunn]

"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."


"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.


The answer is in your own post!

"Would have, could have, should have."

Now shall we compare that Merlin 85 engined Lancaster VI to the B-29D (B-50)?

I've read the Groves quote several times, I suggest (not you Joe) reading it slowly and really taking a good look at what is being said. To me, Groves DOES NOT want to use or even consider the Lancaster, but would be forced to if the Air Force and Boeing didn't get the B-29 sorted out, which I believe he had every confidence they would do so. I find the words "we would have to consider" very enlightening, as I said earlier, to me that means they are not considering it nor do they want to.

Also "This brought from him the characteristic reply that I had hoped and expected to hear" - CLEARLY Groves wanted the B-29 and was banking (rightly so and with good reason) that the Air Force and Boeing would make the necessary modifications and produce a reliable delivery system.

I think also that any good planner has a contingency plan, he may have just been pointing out to General Arnold possibilities if the Superfortress development bogged down too badly.

One other thought is that Groves might have been surreptitiously prodding Arnold to get on the stick and get the 29 sorted so as to be ready at the same time as the gadget.

Again I ask, what would Ramsey have to do with aircraft choice? I imagine it was certainly within his purview to make suggestions but I also imagine that's about all.


Ramsey: We should use the Lancaster.

Arnold: Thanks for the input, now go back to bomb case design bub.

Humor to lighten the moment gentlemen.

 

[SaparotRob]

The article has a few flaws.

It states that the Fatman would not fit into a Lancaster bomb bay without removing the doors, but the maximum width was short enough to have allowed for bulged doors to be fitted. Yes, there would have been some extra drag, but probably little more than that already produced by the radome and would have been largely offset by removal of the mid upper and front turrets.

A major flaw is in the range calculation. The Lancasters that flew the Tirpitz raids from Scotland covered about 2400 miles, and one even managed to fly the mission and return with a hung up bomb and this was achieved by using a 400IG internal Wellington aux tank, for a total of about 2560 IG of internal fuel. By the use of custom internal aux tanks, maximum fuel load of a Lancaster VI, minus the front and upper turrets, whilst carrying a FATMAN would be about 3000IG (with aux tanks fore and aft of the bomb) and a range of ~3000 miles. Like the Silverplate B-29s the mission would use a low-high-low flight profile, so that minimal time is spent at high altitude and initial climb to attack altitude is done with a large amount of fuel (1200-1500IG or ~8600-11000lb) of fuel burned off. However, even this is insufficient range for safe mission planning with a return to Tinian, and so TO from Tinian would involve a mission plan that included landing at Okinawa or Iwo Jima after weapon release.

A 'Silverplate' Lincoln should have been able to fly to and from Tinian with aux bomb bay tanks.

There are no flaws in the "magazine". It's a magazine sensationalizing it's articles like most magazines in a newsstand. It gets that breathless flavor right. Facts are for Walter Cronkite.

 

[pbehn]

I don't figure out why the "black Lancasters" had no markings because they were on some secret project. If something is secret why draw attention to it by having no markings at all? Just mark them up as individual members of a dozen existing squadrons?

 

[SaparotRob]

I don't figure out why the "black Lancasters" had no markings because they were on some secret project. If something is secret why draw attention to it by having no markings at all? Just mark them up as individual members of a dozen existing squadrons?

I like the cut of your jib, mate!

 

[pbehn]

I like the cut of your jib, mate!

Even as a civilian today a plane with no markings at all looks unusual, its like disguising a car by taking the number plates off, the first thing everyone notices is it has no number plates on.

 

[SaparotRob]

There's an airfreight company that flies a white, unmarked 747-100 (?) out of JFK. If that ain't suspicious I don't know what is.

 

[RCAFson]

What would have happened if Hitler was killed in WW1?


And a suggestion, not a decision by any means....
No I'm thinking the XB-44 and using the same wishful thinking you've been using!

In 1943 and early 1944, there was no certainty that the B-29 could be modded to do the task at hand. Groves states that clearly. If the B-29 doesn't work it was either can the entire program or use the Lancaster.

I'm not the only one who states that the Lancaster was seriously considered:


"Scientists working on the atomic bomb quickly realized that the unusual size and weight of the devices--both the tubular "gun-type fission weapon" shape (Little Boy) and the oval plutonium implosion weapon shape (Fat Man)--would be too large to be delivered by a conventional bomber such as the B-17 or the B-24. In October 1943, Dr. Norman Ramsey, a member of the Los Alamos National Laboratory Group, suggested that the only airplane in the U.S. inventory capable of carrying either type of the proposed weapons shapes was the B-29 Superfortress. Even the B-29, however, would require extensive modifications to both its engines and its bomb bay in order to accommodate the enormous weapon.

Prior to the decision to use the B-29, military officials had given serious consideration to using the British Avro Lancaster to deliver the weapon, which the Royal Air Force had used to deliver the 5-ton Tallboy bombs developed in 1944. The Avro Lancaster would have required much less modification, but Major General Leslie Groves, the commander of the Manhattan Project, and General Henry H. Arnold, the Chief of United States Army Air Forces, wished to use an American plane."
Project Silverplate

and:

"It was a display of nationalism by US General Leslie Groves who thought it "beyond comprehension to use a British plane to deliver an American A-bomb" (he wrote his own book, Now It Can Be Told, still in print in many different versions, even a Kindle edition) that tipped the scales in favor of the B-29 being selected over the British Avro Lancaster. While the B-29 was sophisticated for its day—fully pressurized crew compartments, trick bombing radar, remote-controlled gun turrets with computing sights—it cost a staggering five times as much as a Lanc, over $500,000 apiece, which also would have been much easier to modify. It may well be said, and this book certainly leans in that direction, that the Silverplate program redeemed an otherwise problematic (in terms of performance, safety, bombing accuracy) aircraft that had failed to live up to expectations in its role as conventional high-altitude daylight strategic bomber and had been only provisionally successful as a low-altitude nighttime fire bomber." » The Silverplate Bombers: A History and Registry of the Enola Gay and Other B-29s Configured to Carry Atomic Bombs

I don't understand the relevance of the XB-44 as it was too immature to have been considered.

 

[RCAFson]

Again I ask, what would Ramsey have to do with aircraft choice? I imagine it was certainly within his purview to make suggestions but I also imagine that's about all.


Ramsey: We should use the Lancaster.

Arnold: Thanks for the input, now go back to bomb case design bub.

Humor to lighten the moment gentlemen.

Arnold was not Ramsey's superior, nor even Groves' superior, since Groves didn't report to Arnold.

Ramsey:

"EARLY FLIGHT TRIALS AT NPG DAHLGREN
If the Manhattan Project was to succeed, it had to do more than simply build atomic bombs. It also had to fashion a reliable means of delivering those bombs to the enemy. Overall management of atomic weapon delivery was placed in the capable hands of Captain William S. 'Deke' Parsons, USN, and Dr. Norman F. Ramsey. Parsons had been a major player in getting the proximity fuze out to the fleet. Ramsey, a gifted physicist and engineer-organizer, would be the 'fixer' responsible for running day-to-day operations.

The first scale models of the plutonium gun bomb were fashioned by simply cutting a standard 500 pound aerial bomb in half and splicing a length of sewer pipe in between. Test drops were made from a Grumman TBF beginning in August 1943 at the Naval Proving Ground (NPG) range near Dahlgren, Virginia, but the ballistic characteristics of the 'sewer pipe bomb' were truly awful. Upon release, the bomb invariably went into a flat spin and broke up when it hit the ground broadside. Even as revised scale models of the plutonium gun continued to be flight-tested at Dahlgren, however, Norman Ramsey was beginning to scout out a suitable carrier aircraft for the full-sized weapon.

In 1943, there were no aircraft in the US inventory with a bomb bay that could contain a 17 foot bomb. Ramsey did consider modifying a Consolidated - Vultee B-24 Liberator bomber for the purpose, only to abandon the idea when he discovered that the Navy had already tried to reengineer the B-24 for internal torpedo carriage and failed. That left the Boeing B-29 as the only other possible American candidate. During a field trip in August, Ramsey made surreptitious measurements of the Superfortress. He found that it could be adapted for the purpose by combining its two 12 foot bomb bays into one, but only if the bomb was no more than two feet in diameter. The reason was that the two bays were separated by the wing spar carry-through box, and the maximum distance between the lower side of the box and the bottom of the fuselage was no more than two feet.

MS-469: THIN MAN, FAT MAN, AND THE SILVER PLATED PULLMAN
By the late fall of 1943, the ballistic problems of the plutonium gun bomb had been largely solved with improved tail surfaces and better weight balance. As its internal arrangements became more firmly established, the casing's layout was modified to follow suit. The final 'pod' or Cornog model (named after a design team member) featured a rounded, bulbous nose to house the fuzing arrangements and the muzzle plug - the 'anvil' - that was to hold the plutonium target, and a long, slender body with an elongated box tail. The full-size models were 18 feet long, and the design team estimated that the final product would weigh about 7,500 pounds.

Scale model air-drops continued on into the winter at Dahlgren, but it had become obvious that another site was needed. The air near Chesapeake Bay was hazy, and full-sized model testing would have to be conducted from as high as 30,000 feet; good visibility was important. But security was also a concern - there were too many curious eyes in eastern Virginia. Parsons and Ramsey began searching for an alternative test site. In the meantime, Los Alamos scientists and engineers had also made progress in working out the practicalities of an implosion bomb. Its arrangements would be quite different from the plutonium gun weapon, however, and that meant that the search for a suitable bomber had to be expanded. In September, Ramsey was instructed to find an aircraft with a bomb bay that could carry a weapon weighing as much as 9,500 pounds. Unlike the long, slender plutonium gun, this new bomb had to be ball-shaped to contain the bulky explosive charges; Los Alamos' best guess was that the new design could be up to six feet in diameter.

Ramsey quickly concluded that there were only two Allied bombers capable of carrying both weapons: the Boeing B-29 (if suitably modified) and the Avro Lancaster. The Lancaster had ample room internally, and it was a prodigious weight lifter; it almost won the contest. In fact, Ramsey traveled to Canada in October 1943 to meet with Roy Chadwick, the Lancaster's chief designer. As luck would have it, Chadwick had crossed the Atlantic to view Lancasters being built at the Avro Canada works in Toronto, and Ramsey seized the chance to show Chadwick some preliminary sketches of both the gun and the implosion weapon casings. Chadwick assured Ramsey that the Lancaster could accommodate either bomb and promised whatever support might be needed, but he was well-used to wartime secrecy; Chadwick did not ask why the weapons had such unusual shapes."
Operation Silverplate - The Aircraft of the Manhattan Project

 

[FLYBOYJ]

In 1943 and early 1944, there was no certainty that the B-29 could be modded to do the task at hand. Groves states that clearly. If the B-29 doesn't work it was either can the entire program or use the Lancaster.

I'm not the only one who states that the Lancaster was seriously considered:


"Scientists working on the atomic bomb quickly realized that the unusual size and weight of the devices--both the tubular "gun-type fission weapon" shape (Little Boy) and the oval plutonium implosion weapon shape (Fat Man)--would be too large to be delivered by a conventional bomber such as the B-17 or the B-24. In October 1943, Dr. Norman Ramsey, a member of the Los Alamos National Laboratory Group, suggested that the only airplane in the U.S. inventory capable of carrying either type of the proposed weapons shapes was the B-29 Superfortress. Even the B-29, however, would require extensive modifications to both its engines and its bomb bay in order to accommodate the enormous weapon.

Prior to the decision to use the B-29, military officials had given serious consideration to using the British Avro Lancaster to deliver the weapon, which the Royal Air Force had used to deliver the 5-ton Tallboy bombs developed in 1944. The Avro Lancaster would have required much less modification, but Major General Leslie Groves, the commander of the Manhattan Project, and General Henry H. Arnold, the Chief of United States Army Air Forces, wished to use an American plane."
Project Silverplate

and:

"It was a display of nationalism by US General Leslie Groves who thought it "beyond comprehension to use a British plane to deliver an American A-bomb" (he wrote his own book, Now It Can Be Told, still in print in many different versions, even a Kindle edition) that tipped the scales in favor of the B-29 being selected over the British Avro Lancaster. While the B-29 was sophisticated for its day—fully pressurized crew compartments, trick bombing radar, remote-controlled gun turrets with computing sights—it cost a staggering five times as much as a Lanc, over $500,000 apiece, which also would have been much easier to modify. It may well be said, and this book certainly leans in that direction, that the Silverplate program redeemed an otherwise problematic (in terms of performance, safety, bombing accuracy) aircraft that had failed to live up to expectations in its role as conventional high-altitude daylight strategic bomber and had been only provisionally successful as a low-altitude nighttime fire bomber." » The Silverplate Bombers: A History and Registry of the Enola Gay and Other B-29s Configured to Carry Atomic Bombs

OK so now it was "considered," (recommened, whatever) but at the end of the day the bugs were worked out and the superior delivery platform was chosen. You seem to keep driving this home to reflect that the Lancaster, because it was "considered" was the superior platform and it was not, no matter how you try to twist this or emphasize the B-29s teething issues, at the end of the day the B-29 stood a generation ahead over the Lancaster and as I repeated before, that's not taking anything away from the Lancaster.

I don't understand the relevance of the XB-44 as it was too immature to have been considered.

It "could have" easily been accelerated and provided better performance than any other Lancaster or Lincoln mark. I'm now using your rationale.

Arnold was not Ramsey's superior, nor even Groves' superior, since Groves didn't report to Arnold.

Ultimately they ALL worked for Arnold with regards of developing how this weapon was going to be deployed. If you look at the AAF command structure Arnold reported directly to General Marshal. There was also a reporting line from Arnold to the Assistant Sec. of War (for air) Robert Lovett. While Groves was the head of the Manhattan project, he was "just" a Major General. Regardless of how many people you show who "recommended," suggested," "considered" the Lancaster, at the end of the day General Arnold had the final word for the delivery system.

The only "what if" to this is if the bomb was ready earlier and Roosevelt wanted it immediately deployed (as you pointed out). I think Arnold "would have" pushed back and tried to hold out to an American delivery system. Whether he would have been overruled by Marshal, Lovett or even Roosevelt is another "what if" discussion.

 

[pbehn]

From what I read elsewhere, in 50 years time Roosevelt and Arnold will be castigated for not letting the British take the blame for dropping the bomb and in 100 years time it will be common knowledge that an unmarked black Lancaster dropped them both.

 

[RCAFson]

OK so now it was "considered," (recommened, whatever) but at the end of the day the bugs were worked out and the superior delivery platform was chosen. You seem to keep driving this home to reflect that the Lancaster, because it was "considered" was the superior platform and it was not, no matter how you try to twist this or emphasize the B-29s teething issues, at the end of the day the B-29 stood a generation ahead over the Lancaster and as I repeated before, that's not taking anything away from the Lancaster.


It "could have" easily been accelerated and provided better performance than any other Lancaster or Lincoln mark. I'm now using your rationale.



Ultimately they ALL worked for Arnold with regards of developing how this weapon was going to be deployed. If you look at the AAF command structure Arnold reported directly to General Marshal. There was also a reporting line from Arnold to the Assistant Sec. of War (for air) Robert Lovett. While Groves was the head of the Manhattan project, he was "just" a Major General. Regardless of how many people you show who "recommended," suggested," "considered" the Lancaster, at the end of the day General Arnold had the final word for the delivery system.

The only "what if" to this is if the bomb was ready earlier and Roosevelt wanted it immediately deployed (as you pointed out). I think Arnold "would have" pushed back and tried to hold out to an American delivery system. Whether he would have been overruled by Marshal, Lovett or even Roosevelt is another "what if" discussion.

Ramsey stated that the Lancaster was his preferred platform in 1943. I've never stated that the Lancaster VI was superior to the Silverplate B-29s after they were debugged, rather I've stated that the Lancaster VI had the range and performance to have safely delivered either A-bomb design and could likely have done so with TO from Tinian and landing at Okinawa. The Grand Slam modded Lancasters had a range of ~1700 (and ~1700IG of fuel) miles whilst carrying a 22000lb bomb externally at ~.99 AMG. If we substitute a 10000lb bomb and add 11000lb of fuel (1527 IG) we get a maximum range of ~3100 miles (allowing for tropical conditions), which allows for a low-high-low Tinian -> target-> Okinawa mission (~2400 miles) with an ample reserve of fuel. The Lancaster bomb bay has sufficient volume to carry this extra fuel and a FATMAN or LITTLEBOY bomb, if custom aux tanks are added, fore and aft of the bomb. As a check of my data we can look at an actual operational mission: The Tallboy Lancasters operating from Scotland had a range of over 2400 miles with 2560IG of fuel and could have carried another ~700IG of fuel if bomb weight (and length) was reduced by 2000lb and max TO weight increased from 68000 to 72000lb

The Lancaster VI flew in Mid 1943 - it doesn't need to be accelerated, only prioritized (and at a fraction of the cost of the Silverplate B-29 program). Compared to the B-29, the Lancaster VI, even in late 1943 was a more mature and reliable design.

Groves reported directly to the Whitehouse. He only deferred to Marshall and Arnold as a military courtesy.

 

[Tom]

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.

The fact that Arnold wanted an American delivery system is not in doubt, why is the interesting point. Arnold was heavily invested in the B-29 and determined to make it work, for good reason, it was very advanced and offered performance unmatched by any other heavy bomber in service at the time. I don't know what Arnold had in mind as an alternative, but I'm willing to bet that Arnold believed that the B-29 was the only answer, despite its various issues. I'm also willing to bet that regardless of the seriousness of the issues that arose with the B-29 that he was prepared to keep throwing money and resources at it until it was able to do the mission. That it succeeded and carried out the mission using parameters that no other bomber could have flown at the time was evidence that Arnold back the right horse.

There is a good YouTube Podcast by doctor mark Felton, a non aviator academic about this topic. It seems the Lancaster' could probably have done it with in flight refueling. The low top speed and ceiling though would make the blast wave a bit sporty I would think.