The Lancaster as a potential nuclear bomber in 1945

[Peter Gunn]

In reference to Post #381, Bockscar only landed at Okinawa because:

1). A faulty transfer pump isolated ~640 gallons of fuel that could not be offloaded so would be dead weight all the way to Japan and back.

2). Sweeney orbited the RV for 45 minutes although Tibbets ordered him to stay only 15 mins

3). They spent 50+ minutes on three bomb runs at Kokura with no visual on the city so diverted (finally) to Nagasaki where:

4). After a three minute bomb run they dropped Fat Man

The end result is that Bockscar did not have the fuel to make it to the emergency site at Iwo Jima, so Sweeney diverted to Okinawa which was NOT the preferred choice. With that in mind, does anyone really think the Lancaster could have pulled off that mission profile? Remember, no plan survives contact with the enemy, what if that HAD been a Lancaster trying to deliver Fat Man?

Now I'm not saying you couldn't do a Tinian --> Target --> Okinawa --> Tinian but the guys planning the mission in 1945 didn't think that was the way to go, who knows, maybe they were wrong.

And for the record, I don't think the Lancaster, for all its accomplishments and capabilities would have been able to deliver the A-Bomb. Realistically, it was no longer ready for Prime Time anymore, those days were past.

 

[wuzak]

I provided a properly cited source to show that it can carry a FAT MAN bomb.

All the Silverplate mods were fiction until they were done. The Lancaster bomb bay is 33ft by 38in by 61in and there's plenty of room for aux tanks fore and aft of either A bomb design.

Tinian->Japan->Okinawa/Tinian is mostly an overwater flight safe from AA or fighters, which is why even the B-29 flew a low-high-low mission profile. Seriously, you didn't know that?

The 4,000lb HC bomb was 30" in diameter and would fit inside the Lancaster bomb bay.

The 8,000lb HC, 12,000lb HC and 12,000lb Tallboy bombs were 38" in diameter and required bulged bomb bay doors.

The 22,000lb DP Grand Slam bomb was 46" diameter and required the bomb bay doors to be removed - it would not fit inside.

The Fat Man bomb was 60" in diameter.

Your own dimensions show the bomb bay depth (with bulged bomb bay doors) was 38". Fat Man was over 50% bigger than that.

 

[RCAFson]

No...wrong.
Absolutely NO Silverplate missions originated from Okinawa. Period.

All 15 conventional pumpkin bomb test missions were from Tinian.

Both atomic missions were from Tinian.

Bockscar flew Tinian-Nagasaki-Okinawa-Tinian. I've never suggested otherwise.

 

[RCAFson]

The 4,000lb HC bomb was 30" in diameter and would fit inside the Lancaster bomb bay.

The 8,000lb HC, 12,000lb HC and 12,000lb Tallboy bombs were 38" in diameter and required bulged bomb bay doors.

The 22,000lb DP Grand Slam bomb was 46" diameter and required the bomb bay doors to be removed - it would not fit inside.

The Fat Man bomb was 60" in diameter.

Your own dimensions show the bomb bay depth (with bulged bomb bay doors) was 38". Fat Man was over 50% bigger than that.

Grand Slam's length is a issue but there was no operational need to enclose it. FAT MAN is about 12ft shorter IIRC.

So with all the resources at their disposal, the 'Silverplate' team can't fabricate bomb bay doors to enclose FAT MAN? They had no problem spending 6000 man hrs to mod a B-29. The easiest way to do it would be to cut away an opening so that the doors close around the bomb.

 

[RCAFson]

In reference to Post #381, Bockscar only landed at Okinawa because:

1). A faulty transfer pump isolated ~640 gallons of fuel that could not be offloaded so would be dead weight all the way to Japan and back.

2). Sweeney orbited the RV for 45 minutes although Tibbets ordered him to stay only 15 mins

3). They spent 50+ minutes on three bomb runs at Kokura with no visual on the city so diverted (finally) to Nagasaki where:

4). After a three minute bomb run they dropped Fat Man

The end result is that Bockscar did not have the fuel to make it to the emergency site at Iwo Jima, so Sweeney diverted to Okinawa which was NOT the preferred choice. With that in mind, does anyone really think the Lancaster could have pulled off that mission profile? Remember, no plan survives contact with the enemy, what if that HAD been a Lancaster trying to deliver Fat Man?

Now I'm not saying you couldn't do a Tinian --> Target --> Okinawa --> Tinian but the guys planning the mission in 1945 didn't think that was the way to go, who knows, maybe they were wrong.

And for the record, I don't think the Lancaster, for all its accomplishments and capabilities would have been able to deliver the A-Bomb. Realistically, it was no longer ready for Prime Time anymore, those days were past.

Sweeney was roundly criticized for his mission plan and TO with a faulty fuel pump, but then again, he also calculated his available fuel and the possibility of diverting to Okinawa. if Sweeny had even less fuel he would have made different decisions.

 

[glennasher]

Presumably, the Lancaster couldn't do carry "the bomb" without air-to-air refueling, which wasn't a common thing in those days, and the Lanc wasn't set up for that anyway. How long would it take to develop the capability to refuel in the air? How would that be any better than waiting to finish development of the B-29?
It seems to me that even thinking about using the Lancaster just isn't a good way to spend the time and effort.

 

[RCAFson]

Presumably, the Lancaster couldn't do carry "the bomb" without air-to-air refueling, which wasn't a common thing in those days, and the Lanc wasn't set up for that anyway. How long would it take to develop the capability to refuel in the air? How would that be any better than waiting to finish development of the B-29?
It seems to me that even thinking about using the Lancaster just isn't a good way to spend the time and effort.

The Lancaster can carry the bomb without air to air refuelling. However, air to air refuelling was quite feasible and was another alternative:


In 1934, Cobham had founded Flight Refuelling Ltd and by 1938 had used FRL's looped-hose system to refuel aircraft as large as the Short Empire flying boat Cambria from an Armstrong Whitworth AW.23.[5] Handley Page Harrows were used in the 1939 trials to perform aerial refueling of the Empire flying boats for regular transatlantic crossings. From August 5 to October 1, 1939, sixteen crossings of the Atlantic were made by Empire flying boats, with fifteen crossings using FRL's aerial refueling system.[14] After the sixteen crossings further trials were suspended due to the outbreak of World War II.[15] Aerial refueling - Wikipedia

However, given the low cost of the aircraft, compared to the bomb, ditching the aircraft after the mission is no big deal, especially as the Allied navies had near complete control of the seas.

 

[FLYBOYJ]

However, given the low cost of the aircraft, compared to the bomb, ditching the aircraft after the mission is no big deal, especially as the Allied navies had near complete control of the seas.

Hmmm....

What about the cost of the crew's lives? Fly a cheaper but inferior aircraft on one of the most important missions of the war with a nuclear device and attach a ditching requirement on the crew after they just nuked a major population center. And that's if everything worked out.

I am so glad this was all a "what if" perspective. Yea, I believe a Lancaster or Lincoln "could have" achieved a nuclear mission, based on arguments on both sided of this discussion it's clear that the way history played out WAS the better option!!!

 

[RCAFson]

Hmmm....

What about the cost of the crew's lives? Fly a cheaper but inferior aircraft on one of the most important missions of the war with a nuclear device and attach a ditching requirement on the crew after they just nuked a major population center. And that's if everything worked out.

I am so glad this was all a "what if" perspective. Yea, I believe a Lancaster or Lincoln "could have" achieved a nuclear mission, based on arguments on both sided of this discussion it's clear that the way history played out WAS the better option!!!

I'm just saying that the crew had lots of options to successfully complete a mission, including ditching at a number of prearranged locations. Sweeny avoided ditching by about 2mins as he basically began running out of fuel at touch down.

 

[FLYBOYJ]

I'm just saying that the crew had lots of options to successfully complete a mission, including ditching at a number of prearranged locations. Sweeny avoided ditching by about 2mins as he basically began running out of fuel at touch down.

Well aware about Sweeney's situation, that's called "PILOT ERROR," a little different from a planned ditching to fulfill the most important mission of the war!

 

[RCAFson]

Well aware about Sweeney's situation, that's called "PILOT ERROR," a little different from a planned ditching to fulfill the most important mission of the war!

Sweeny was aware that a successful drop might end the war. Yes, he gambled his aircraft and the lives of his crew against the possibility of forcing Japan to surrender. If Sweeny had to wait even longer to strike a target, and then ditched, (and there were prearranged locations for that) he would still have accomplished his mission. A 'Silverplate' Lancaster wouldn't have to ditch either, but if it did then it's just the cost of doing business.

 

[swampyankee]

Hmmm....

What about the cost of the crew's lives? Fly a cheaper but inferior aircraft on one of the most important missions of the war with a nuclear device and attach a ditching requirement on the crew after they just nuked a major population center. And that's if everything worked out.

I am so glad this was all a "what if" perspective. Yea, I believe a Lancaster or Lincoln "could have" achieved a nuclear mission, based on arguments on both sided of this discussion it's clear that the way history played out WAS the better option!!!

I think the reasoning is essentially that none of the US bombers except the B-29 had a chance of carrying either Little Boy or Fat Man; the Lancaster could with some level of difficulty. The B-32 may have been able to, but its development was even more protracted and troublesome than that of the B-29. The XB-44 didn't fly until May 1945. The XB-39, which may have been one of the missed opportunities, didn't fly until December 1944.

There was no US-built fallback aircraft to deliver the atomic bomb. On the other hand, the bomb was not developed to attack Japan: it was developed to attack Germany. Any planning of carrier aircraft would have been with that in mind.

 

[GrauGeist]

It was important that the bombers returned as the both had mission data and top secret equipment on board.

We have the luxury of looking back and making suggestion about the entire program, but what we know about the aircraft and missions today, would have most likely gotten us shot in 1945.

 

[Graeme]

Don't know if this will help any

This probably won't either - an amateurishly hand drawn profile shot (hoping my scaling is right).

 

[GrauGeist]

Keep in mind that both Little Boy and Fat Man had to be manually armed by the weaponeer while in flight.

 

[RCAFson]

Keep in mind that both Little Boy and Fat Man had to be manually armed by the weaponeer while in flight.

Groves, In Now it can be told disputes this, and states that the arming in-flight was an unnecessary complication, and that the local commanders were overstepping their authority in insisting on that. The bombs were not really designed for in-flight arming.

 

[GrauGeist]

And yet, they were...

 

[GrauGeist]

As an aside, read about Dick Ashworth, who was the weaponeer aboard Bockscar:

Frederick Ashworth, 93; Weaponeer on Plane That Dropped 2nd A-Bomb

 

[ThomasP]

In a mechanical function sense there was no reason that the bombs had to be armed the way they historically were while in flight, or in any way in flight, except maybe a final arming switch for the fuze(s). Possibly it was considered a safety or security requirement by the local commanders and other higher-ups?

 

[GrauGeist]

Again, we're looking back at 1944/45 technology with 21st century eyes.

The bombs were manually armed and in the event on an emergency, disarmed.

Fears of RFI, static electricity and other issues made the weaponeer's job of manually arming/disarming a priority.

These Uranium and Plutonium bombs were completely new technology and there was no real database of "does and don'ts" that existed.
Of course, if they screwed up, then that would certainly be something not to do next time...