# B-29 reset



## gjs238 (Apr 12, 2014)

Knowing of the Wright R-3350 Duplex-Cyclone reliability issues extended development time, could we turn back the clock and get the B-29 deployed sooner using different engines or engine arrangements?


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## vikingBerserker (Apr 12, 2014)

I wonder if it could have been fitted with diesel engines for longer range.


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## Piper106 (Apr 12, 2014)

Historically, we were within *striking distance* of having the B-39, a B-29 with Allison V-3420 engines. 

In interest of full disclosure, in history the on again off again on again priority placed on the V-3420 meant that the B-39 timeline was did not work out, so historically *striking distance* maybe was not too close. 

In the "could have been" universe, the B-39 had just as much development potential as the B-29 / B-29D aka B-50 timeline. 
A late model B-39 with leading edge radiators, and a VDT version of the V-3420 could have been an impressive performer.


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## tomo pauk (Apr 12, 2014)

Conceive the 'big bomber' around the R-2800 engines.


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## gjs238 (Apr 12, 2014)

tomo pauk said:


> Conceive the 'big bomber' around the R-2800 engines.



Six engines?
Or a more modest 4-engined plane?


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## gjs238 (Apr 12, 2014)

From Wikipedia:
_The first R-3350 was run in May 1937. Continued development was slow, both due to the complex nature of the engine, as well as the R-2600 receiving considerably more attention. The R-3350 did not fly until 1941, after the prototype Douglas XB-19 had been redesigned from the Allison V-3420 to the R-3350.
Things changed dramatically in 1940 with the introduction of a new contract by the USAAC to develop a long-range bomber capable of flying from the US to Germany with a 20,000 lb (9000 kg) bomb load. Although smaller than the Bomber D designs that led to the B-19, the new designs required roughly the same amount of power. When preliminary designs were returned in the summer of 1940, three of the four designs were based on the R-3350. Suddenly the engine was seen as the future of army aviation, and serious efforts to get the design into production started._


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## tomo pauk (Apr 12, 2014)

gjs238 said:


> Six engines?
> Or a more modest 4-engined plane?



4 engines. Though, it would not be a modest A/C


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## pbehn (Apr 12, 2014)

Bearing in mind the massive cost of the B 29 project would it have been possible with such money thrown at it from the start to make it the first Jet bomber? Just a question.


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## wuzak (Apr 12, 2014)

pbehn said:


> Bearing in mind the massive cost of the B 29 project would it have been possible with such money thrown at it from the start to make it the first Jet bomber? Just a question.



I would think no. Because of the range requirements, the early jets being notoriously thirsty, and because the jets at the time of the B-29's development were not pwerful enough. By the time decently powerful jets started to show up the B-29 was in production.


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## wuzak (Apr 12, 2014)

Piper106 said:


> In the "could have been" universe, the B-39 had just as much development potential as the B-29 / B-29D aka B-50 timeline.
> A late model B-39 with leading edge radiators, and a VDT version of the V-3420 could have been an impressive performer.



VDT was a P&W thing. And also problematic.

One R-4360 VDT test engine flew in a B-50 in the late 1940s. As no suitable control mechanism had been designed, the flight engineer had to constantly monitor and adjust the nozzle to control the turbo. In a V-3420 powered B-29 variant that would require monitoring and adjusting 8 turbos.

Allison's development bent was turbo-compound. Given that a V-1710-127 (-E27) turbo-compound engine could develop around 3000hp at take-off, maybe that could have been used. Would have had less power than the R-3350 version at altitude, though.

A TC version of the V-3420 could have been well over 5000hp at take-off. But it would have needed a new turbine unit designed.


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## nuuumannn (Apr 12, 2014)

How about fitting it with Shvetsov M-71 or M-72? Tupolev Tu-4 was powered by a development of the 2,250 hp M-72, the 2,400 hp ASh-73 TK-19. Arkadiy Shvetsov was engaged in building Wright engines under licence in the 1930s

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## GrauGeist (Apr 12, 2014)

vikingBerserker said:


> I wonder if it could have been fitted with diesel engines for longer range.


Diesel engines don't do well at high altitude


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## wuzak (Apr 12, 2014)

GrauGeist said:


> Diesel engines don't do well at high altitude



Tell that to the Ju 86P and R.

The real problem is, were there suitable and sufficiently powerful Diesel engines available in the USA?


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## GrauGeist (Apr 12, 2014)

The problem with diesel at high altitude, is that it conceals. A diesel engine also lacks a quick throttle response-time. Otherwise, they are great for long range aircraft, like the Bv138.

As far as American diesel aircraft engines are concerned, Packard built a radial diesel in the late 20's and it was used in a variety of aircraft.


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## wuzak (Apr 12, 2014)

GrauGeist said:


> The problem with diesel at high altitude, is that it conceals. A diesel engine also lacks a quick throttle response-time. Otherwise, they are great for long range aircraft, like the Bv138.
> 
> As far as American diesel aircraft engines are concerned, Packard built a radial diesel in the late 20's and it was used in a variety of aircraft.



Quick throttle response is not usually required for long range bombers.

he Packard Diesels, were they in the 2000-2500hp class?


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## GrauGeist (Apr 12, 2014)

wuzak said:


> ...he Packard Diesels, were they in the 2000-2500hp class?


Nooo...not even close! 

While the DR-980 was used in some military applications, it wasn't a large engine (only 9 cyl.)

It was rated at 240hp (179kw) @ 2,000 rpm and had a power to weight ratio of .44hp/lb (.8kw/kg)

It was a good engine and I understand that the Russians even copied it.


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## GregP (Apr 13, 2014)

A 4-engine R-2800 B-29 would be anemic and not worth the effort. They did it the right way, persevering with the R-3350 and working through the troubles.

Had they tried a 6-engine B-29 with R-2800's ... maybe. But it seems overly complex and expensive.

The way they did it in real life sealed the deal in the Pacific and was a very capable weapon.


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## tomo pauk (Apr 13, 2014)

Greg, why would a big bomber with forur R-2800s be anemic? Any numbers?


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## GregP (Apr 13, 2014)

The B-29 was always a bit underpowered. The early R-2800 developed 1,500 HP in 1939 and 1,850 some 12 or so months later. But 1941 it was making 2,000 HP at max approved boost and rpm.

The FIRST R-3350 made 2,250 HP in 1937 and languished a bit while the R-2600 was developed. It first flew in 1941 at that same HP, but was stretched to 2,800 and ginally 3,500 HP after the war. During the war it always made more HP than the R-2800.

What could have happened if they had concentrated in the R-3350 when it first came out? We already know ... it COULD have been developed as many as 5 years sooner to the same levels it was ...because it actually happened, only 5 years later.

So, say the B-29 would cruise at 60 % power, albeit not especially fast at that power, then 60% of 2,200 HP is 1,320 HP each. The R-2800 in 1941 was making 1,200 HP. If you fly THAT at 60% power you get 1,200 HP, or an aggregate of 480 HP less with the R-2800 in cruise (assuming 60% power). It's 800 HP less at max power, not inconsequential. Actually it's 10% more power than the R-2800 made and max boost.

The B-29 could make 357 mph on four 2,200 HP R-3350's and they regularly attacked Japan at 325 mph+, making them very hard to catch and shoot down for the Japanese at the time. Had they used the 2,000 HP R-2800, the top speed would likely be in the 346 mph range with a commensure drop in over-the target-speed to around 314+ mph, maybe less. That's maybe catchable even for a Zero at 20,000 feet and would render the plane a bit more vulnerable. I can't say how much MORE vulnerable, but a bit more.

Once the R-3350 developed to 2,800 HP, the R-2800 was left far in the dust as a bomber engine. Yes, I KNOW it made a lot of power in experimental models but, for WWII is was basically a 2,000 to 2,200 HP engine at war emergency power. The R-2800 wasn't going to swing the same prop at the same speed as the R-3350, so the predicted data above are probably optimistic. Basically, I don't believe a plane known for being a bit underpowered could afford to lose 480 HP at cruise and 800 HP at top speed and still have the very effective bomb load the B-29 had.

Could it have flown with R-2800's? Sure.

Would it have been as effective as what was done? That's a what-if that nobody can answer ... they never DID it, so any opinion is as good as another.

I would not have gone that route and they historically didn't, either. But I suppose it MIGHT have resulted in more B-29's to the point that maybe they could have been deployed to Europe as well as the Pacific, I don;t know. Had THAT eventuality happened, it could have made a huge difference ... but is, again, a what-if that can be argued either way.

They MAY have even considered that option and discarded it, so the opportunity was recognized and not implemented, I don't know. I DO know the B-29 was very effective and hard hitting, with the heaviest normal bomb load of the war by a bomber in large scale production. 

Don't even tell me about Grand Slams ... they were never a "normal" bomb load and the Lancasters that carried them were structurally in dangerous waters. It was done out of necessity, not with any regularity. They dropped a total of 42 Grand Slams in the entire war, less than .03% of Lancaster sorties.


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## tomo pauk (Apr 13, 2014)

Greg,
Under what conditions the R-3350 was making 2800 HP in the ww2? The R-2800-57 in the P-47M and N was making 2800 HP (war emergency power) and 2100 HP for take off. The 1st such engines were in service in late 1944 on P-47Ms and often problematic, bugs were ironed out by the time P-47N entered combat (May 1945). OTOH, it took some time to get R-3350s to be dependable.
The bomber designed around the R-2800s should be tad a smaller than B-29, so the speed should be in the ballpark.
The usual bomb load for the Lancaster included the 12000 lb cookie (three 4000 lb cookies 'glued' one after another) and bunch of small incendiaries, the Fat Man weighted 10300 lbs, Little Boy was at 9700 lbs. The Tallboy, another Lanc's bomb, was at 10000 lbs.


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## gjs238 (Apr 13, 2014)

Perhaps a R-2800 powered Martin XB-33 Super Marauder.
https://en.wikipedia.org/wiki/Martin_XB-33
Thinking the 4-engined version.

Or at least something along these lines.


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## GregP (Apr 13, 2014)

If the "B-29" developed around the R-2800 had been smaller, then the bomb load would have been commensurately less. So you are basically talking about a new bomber development in lieu of the real B-29. That is certainly possible, but never happened. If it had, it would have replaced the B-29 program since Boeing only had so many development teams.

Of course it COULD have been done, and nobody can say how it might have done in the war ... we KNOW how the real B-29 did, and it hit hard and fairly accurately. It was tough to shoot down due to speed over target and carried a bomb load that 5 B-17's carried from London to Berlin. The B-17 COULD carry a lot, but not all that far. The B-29 could do both.

So yes, they COULD have developed the B-29 alternately with smaller engines, but the real question is "Why"? As actually done it proved decisive and reduced its targets to rubble, whether from fire bombs, conventional bombs, or atomic bombs, and did so from long ranges.

The B-17 in Europe flew 192,508 sorties and dropped 640,032 short tons of bombs, had 4,688 losses, and claimed 6,659 enemy A/C destroyed. It delivered 2.2 short tons per sorties and flew 62.2 sorties per loss.

The B-29 in the Pacific flew 31,387 sorties and dropped 159,676 short tons of bombs, had 414 losses, and claimed 213 enemy A/C destroyed. It delivered 5.1 short tons per sorties (twice that of the B-17) and flew 75.8 sorties per loss.

So the B-29 had a lower loss rate, delivered twice the bombs (or could use half the planes, alternately), and was more than 100 mph faster over the target. What cannot be seen here is that operational losses accounted for a lot of B-29 losses. I believe they lost something like 121 to enemy A/C, but can't find that number just now ... it's from recent memory.

All in all, I like flying fewer sorties or, alternately, dropping more bombs so you'd have to revisit targets much less frequently. The B-29 acquitted itself quite well in the Pacific and would have been devastating in the ETO had it been deployed there, if due only to dropping twice as many bombs per plane per sortie. That is, of course, a "what-if" on my part, but the rest is not.

I think as designed the B-29 was the best heavyweight bomber of the war, and was the only super heavyweight.

The Lancaster carried, on average, about 80% of the bomb load of the B-29 and had twice the loss rate. It was easily the best heavy bomber in the ETO. But it didn't quite perform like the B-29 did in the Pacific and, to be fair to the mighty Lanc, was never ASKED to do so. One could argue how the Lanc might have done in the Pacific, but not very effectively since it never happened to any degree. It's like speculating on how the B-29 might have done in the ETO, which ALSO never happened to any great degree.

In the end, the B-29 dropped the heaviest loads over the longest distances with a very good loss rate. In fact, the loss rate of the B-29 in combat was very slightly less than the loss rate of the Mosquito bomber which has been deemed, at least in HERE, as almost untouchable. That statement is based on a B-29 loss rate of 0.0132 losses per sortie for the B-29 against a loss rate of 0.0138 losses per sortie for bomber command Mosquitoes (39,795 sorties against 396 losses). People in here are constantly saying we should have adopted the Mosquito to help our cause. Perhaps they should have adopted the B-29 as designed instead of the Mosquito bomber if loss rate, bomb load, and range are the keys to the better plane?

I'd stay with the B-29 as designed and as utilized, but that is just my opinion. But if someone wants to speculate about alternate bombers, be sure you have the formula for a plane that would perform better than the real heavy bomber with the best recorded performance of WWII for the combination of range, bomb load, and speed for a 4-engine bomber. It seems to be damned hard to beat the B-29. I can't find another heavy that did as well.

The A-26 Invader (lowest loss rate for ANY bomber I can find), A-20 Havoc, and B-26 Marauder all had lower loss rates than the B-29, and WAY better than the Mosquito bombers, but didn't deliver the bomb load of a heavy. They were more for pinpoint raids, like the Mosquito for the RAF.


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## tomo pauk (Apr 13, 2014)

Ask a simple question, and be prepared to read an essay 



GregP said:


> ....
> 
> So yes, they COULD have developed the B-29 alternately with smaller engines, but the real question is "Why"? As actually done it proved decisive and reduced its targets to rubble, whether from fire bombs, conventional bombs, or atomic bombs, and did so from long ranges.



Why? To have a workable big bomber in early 1943.

....



> All in all, I like flying fewer sorties or, alternately, dropping more bombs so you'd have to revisit targets much less frequently. The B-29 acquitted itself quite well in the Pacific and would have been devastating in the ETO had it been deployed there, if due only to dropping twice as many bombs per plane per sortie. That is, of course, a "what-if" on my part, but the rest is not.



Everyone loves that. Hence this thread - start with benefits already in 1943.



> I think as designed the B-29 was the best heavyweight bomber of the war, and was the only super heavyweight.



Agreed.



> The Lancaster carried, on average, about 80% of the bomb load of the B-29 and had twice the loss rate. It was easily the best heavy bomber in the ETO. But it didn't quite perform like the B-29 did in the Pacific and, to be fair to the mighty Lanc, was never ASKED to do so. One could argue how the Lanc might have done in the Pacific, but not very effectively since it never happened to any degree. It's like speculating on how the B-29 might have done in the ETO, which ALSO never happened to any great degree.



Lets not compare incomparable. Lanc flew in a far more dangerous air space, and was in the fray far earlier then B-29. Although, the B-29 should be a more survivable platform, un-catchable for German night fighters. So would 'my bomber'.
I have no problems in thinkering of Lanc in the Asia/Pacific, nor of B-29 in Europe. 



> I'd stay with the B-29 as designed and as utilized, but that is just my opinion. But if someone wants to speculate about alternate bombers, be sure you have the formula for a plane that would perform better than the real heavy bomber with the best recorded performance of WWII for the combination of range, bomb load, and speed for a 4-engine bomber. It seems to be damned hard to beat the B-29. I can't find another heavy that did as well.



B-52 was kinda better, but was tad a too late 
It i snot a question of envisioning the better bomber than B-29, but an earlier one.



> The A-26 Invader (lowest loss rate for ANY bomber I can find), A-20 Havoc, and B-26 Marauder all had lower loss rates than the B-29, and WAY better than the Mosquito bombers, but didn't deliver the bomb load of a heavy. They were more for pinpoint raids, like the Mosquito for the RAF.



Neither A-20, nor A-26, nor B-26s were flying 1000 miles above German-held Europe to bomb something, without escorts, during daylight. 
Mosquito did.


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## GregP (Apr 13, 2014)

Well Tomo,

It is possible to develop something, for sure. Several somethings WERE proposed and were not selected to proceed. And a couple of somethings had already BEEN developed, the B-17 and B-24. The B-29 was developed to take the next step. Seems to me you want to have another successive development in between the new plane and the B-29.

While you COULD, the B-29 might never have been developed since it was probably the single most difficult weapon system developed in the USA during the war. Draining resources from the real B-29 program may have caused it to never get service ready.

So, I'd stick with the B-29 as it was developed, if given the choice. I can find no real fault with the B-29 as developed in real life other than a desire to have Wright concentrate on the R-3350 five years sooner.

If not given that choice, then let the alternate history fans come up with the plane, further speculate the performance, and then further speculate the defectiveness in whatever theater they decide to assign it to. I'm sure you (the plural sense, not specifically you, Tomo) can speculate the way to a better outcome. It seems to happen frequently. Naturally, I'd support a better, quicker outcome, but am skeptical it could really happen all by development of a lesser-performing, smaller B29 a bit sooner. Doesn't seem like a game changer on the face of it.

Then again, I might be wrong there.

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## pbehn (Apr 13, 2014)

GregP said:


> Don't even tell me about Grand Slams ... they were never a "normal" bomb load and the Lancasters that carried them were structurally in dangerous waters. It was done out of necessity, not with any regularity. They dropped a total of 42 Grand Slams in the entire war, less than .03% of Lancaster sorties.



Grand slams took an age to make as did the tall boys, it was a specialist weapon, I don't thing of much use against Japanese targets Japan is a volcanic group of islands even a grand slam doesn't penetrate Granite so well/


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## FLYBOYJ (Apr 13, 2014)

The B-29 was one of the most advanced weapons of WW2 IMO, 2nd to the Atomic bomb. It would only seem likely that there would be issues in it's development, especially with the pentagon pushing to get it deployed. In the end both B-29 and 3350 became very useful and reliable machines, but I think this thread would be more appropriate being titled "R-3350 reset."


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## gjs238 (Apr 13, 2014)

B-29 (and R-3350) development and service implementation took much too much long.
The goal, as Tomo stated, is to get this thing in the air dropping bombs earlier.

For all intents and purposes, bombing Japan from China was a failure. A major reason for this was the B-29.
I suspect that even if the folks who started this project (the B-29) knew how protracted it would be, they would have gone down a different avenue.

So how do we get the B-29 in the air earlier?
Different engines? How about V-3420's?

If it is impossible to get the B-29 in the air earlier, what can we get in the air earlier?
Something with four R-2800's?


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## FLYBOYJ (Apr 13, 2014)

gjs238 said:


> For all intents and purposes, bombing Japan from China was a failure. A major reason for this was the B-29.


Half of the problem was the machine, the other half of the problem were the people running the show. The machine could be (and was) fixed.


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## GrauGeist (Apr 13, 2014)

gjs238 said:


> If it is impossible to get the B-29 in the air earlier, what can we get in the air earlier?
> Something with four R-2800's?


You would have the option to stay with the B-17 and B-24 which were already proving effective in the campaigns of the MTO and ETO

There were also other projects under development that could be ramped up or reconsidered.

The XB-15 was intended to use the Allison V-3420 but used the P&W R-1830 instead, because at the time of development (mid-1930's) they weren't available. It's performance was good for it's time but the B-17 would prove to be better. I just threw this in there because it used liquid-cooled engines in a heavy bomber design. As a side-note, the XB-15 prototype was converted into a transport (XC-105) and was operated (sometimes on anti-sub patrols) for the duration of the war, seeing it's last service in 
June 1945.

The XB-19 first flew in 1941, powered by the Wright R-3350 but were changed out to Allison V-3420-11 later on. This project never became a priority even though it proved to have a range over 4,200 miles (6,800 km) and reached altitudes over 39,000 feet (12,000 m). It's one shortcoming was it's slow speed.

The XB-39 was spun off of the B-29 program, using Allison V-3420-17 engines instead of the radial. It's performance was impressive, with a range of 6,290 miles (10,060 km) and could operate at altitudes of 35,000 feet (11,000 m). It's top speed was 405mph (648kph). This project died on the vine due to the demand of turbo-superchargers elsewhere.

The B-32 was developed in the event of the B-29's failure and it's development was lethargic. If the B-29 couldn't get in the air because of the R-3350, then this project wouldn't be a good alternative because it's design relied on them. Changing the engines in this project would be the same as changing the engines in the B-29, and now we've lost time and initiative and are back to square 1.


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## GregP (Apr 13, 2014)

I like the V-3420, and had the R-3350 been a failure (and there are those who say that in WWII it was ...) it was a possibility. The aircraft had good performance and might have been a good one.

Maybe they should have tried the V-3420 on the Beech A-38 as well as the B-29 airframe.


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## GrauGeist (Apr 13, 2014)

GregP said:


> Maybe they should have tried the V-3420 on the Beech A-38 as well as the B-29 airframe.


The XB-39 proved to be capable of the same war load as the B-29, but was actually faster and had a higher capable altitude overall.

The initial tests were done without the turbo-superchargers installed and made impressive runs. Once the turbo-superchargers were installed, it returned even better results.

But the decision was made to stay the course with the radials in the current B-29 design instead.


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## wuzak (Apr 13, 2014)

GrauGeist said:


> You would have the option to stay with the B-17 and B-24 which were already proving effective in the campaigns of the MTO and ETO
> 
> There were also other projects under development that could be ramped up or reconsidered.
> 
> ...



The XB-19 was converted to V-3420s as a part of the B-29 program. Fisher designed a quick engine change module for the V-3420 which would bolt up to the R-3350's firewall, and thus would, theoretically, be a bolt up unit for the B-29.

The V-3420 QEC module used experimental turbos, not the production ones as used on the B-29. The R-3350 in the B-29 used two B-series turbos - which would also have been sufficient for the V-3420 too.

Then Allison and Fisher had their V-3420 efforts diverted to the P-75 program. This delayed testing of the XB-39, which happened after the B-29 was in series production.


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## wuzak (Apr 13, 2014)

GrauGeist said:


> The XB-39 proved to be capable of the same war load as the B-29, but was actually faster and had a higher capable altitude overall.
> 
> The initial tests were done without the turbo-superchargers installed and made impressive runs. Once the turbo-superchargers were installed, it returned even better results.
> 
> But the decision was made to stay the course with the radials in the current B-29 design instead.



The decision was to not interrupt production.


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## GrauGeist (Apr 13, 2014)

wuzak said:


> The decision was to not interrupt production.


Perhaps my summary was too short?


> But the decision was made to stay the course with the radials in the current B-29 design instead


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## FLYBOYJ (Apr 13, 2014)

Remember folks, as the first B-29s were rolling out of the factory, the AAF had their eye on this...

Boeing B-29D/XB-44 Superfortress

As Greg mentioned earlier, the B-29 was a little underpowered.

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## gjs238 (Apr 13, 2014)

All a day late and a dollar short.
How do we get this crate to successfully bomb Japan from China, earlier than historical and w/o all the mechanical losses.


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## GregP (Apr 13, 2014)

We really don't get it there any faster. Until the defeat of Germany, the Pacific was of secondary importance at LEAST to the USA. They concentrated on the ETO and possibly the MTO/North Africa to the detriment of the PTO, and rightfully so. 

We knew fighting a 2-front war was a losing proposition, and Hitler found that out the hard way. When the ETO was won, there was a massive shift to the PTO and then it, too, was won in fairly short order.

The USA historically didn't NEED the B-29 until we got it, and then we concentrated it in the PTO where it did yeoman service.

I think maybe you're looking for a problem were none existed. We did it the right way at the right time. Why mess with a winning strategy that worked very well by playing with one of the major weapons that won the PTO war?


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## gjs238 (Apr 13, 2014)

GregP said:


> I think maybe you're looking for a problem were none existed.



You're joking right? The B-29/R-3350 issues are legendary and well written about.


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## GregP (Apr 13, 2014)

Not joking at all. The B-29 had issues, yes, but also the lowest loss rate of any heavy bomber.

Would have been nice if Wright had passed over the R-2600 and had developed the R-3350 5 years sooner but, in the end, it performed just fine as it was with the heaviest bombloads carried the farthest distances and delivered at the highest speeds of any WWII heavy bomber. Sure, some things could have been fixed sooner, but the record says it did just fine ... excellent, in fact.


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## m37b1 (Apr 14, 2014)

Why not six R2800's? Inner nacelles configured in a push pull arrangement. Very little change to the basic air-frame. Could that have made a serviceable B-29 sooner, while the R3350's were being ironed out? What would the performance be?


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## m37b1 (Apr 14, 2014)

As for diesels. Caterpillar converted R1820's to diesel for tank use. However, this was not optimized for aviation. (poor HP to lb ratio - 450HP @ 2000 RPMs). It did prove to be an excellent tank engine, albeit a very expensive one. Only used in the M-4A6. Not sure what adding boost and injecting more fuel would have done, given injection tech at the time.


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## GregP (Apr 14, 2014)

The question is not why not six R-2800's but, rather, what was so wrong with the plane that had the lowest loss rate, heaviest bomb load, and fastest attack speed in WWII for its's class of aircraft?

Why do you need to improve on the the best? ... especially since it was made obsolete very shortly after its heyday. Jet bombers were the rage 5 - 8 years after WWII, but during 1944 /1945, the B-29 was the pinnacle of excellence. It was made even better by the addition of the R-4360 in the form of the B-50 / KB-50. It was copied by the Soviets in it's entirely, surely the rarest form of flattery. 

And you feel the need to thy to improve it?

I like just as it was, but wish you luck in your improvement program. It might win the war several days sooner. I can't say or argue it with any facts.


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## wuzak (Apr 14, 2014)

Not improve - make it more reliable and available earlier. Though just changing the engines may not have helped getting it operational earlier, due to other systems also causing issues/delays.


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## tomo pauk (Apr 14, 2014)

The historical B-29 was upgraded with Wasp Major engines. So why not up-engine the 'big bomber' with R-3350s for 1945?

The bomber that cruises at 300+ mph will be within the AAA envelope a 1/3rd less time than a B-17, that cruised at 200+ mph. A faster target is also a tougher target to hit. The exposure time against defending fighters will be also substanitially shorter. The heavy fighters trying to lob rockets on bombers stand no chance to make an impression. Once proper escorts are introduced, they don't have to ess in order not to overtake bombers, thus incresing their range.


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## GregP (Apr 14, 2014)

Good points, Tomo. I have no resistance to improving the B-29.

I resist the notion to make it less than it was because it achieved such great success as deployed in real life, with good speed, bomb load, range, and loss rate.

For instance, I didn't really like the He 177 but DO like the He 277 with 4 engines I seriously wonder how it might have gone if they had developed and produced the He 277 a lot sooner. But I have no *operational* data for factual comparison, so it is speculation on my part only. It might be the planes produced would not do any more than the planes actually produced. 

I can't say.


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## GrauGeist (Apr 14, 2014)

In reality, had the USAAF insisted on the Allison powered B-29 (XB-39) and devoted resources to it's production when it showed better performance early on, then there may have been a much different outcome for the B-29 as history remembers it.

But the B-36 project for strategic intercontinental abilities was also in the works (although pushed to the back burner after England turned the tables on Germany's assault). This too, could have been pushed to the front of development and production if the USAAF had felt it was a priority.


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## GregP (Apr 14, 2014)

Yeah, the V-3420 B-29 could have been a good one. I also might have developed the faults of the He-177 if run enough hours. If the seams along the inside and are not torqued properly it, too, may be leaked oil and caused fires. Having worked on Allisons I THINK not, but I could be wrong.

I would like to have seen it at least tried, especially WITH a turbocharger setup. We'll Probably never really know.

We DO know the performance numbers and they were good. That doesn't exactly translate into combat effectiveness, but gives an indication of what was possible.

I like the concept, especially the QEC option.


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## wuzak (Apr 14, 2014)

Getting a reliable B-29 into production earlier may have allowed the USAAF to deploy them to where they were needed when they were needed most. ie in the ETO in late 1943/early 1944.

Had they been deployed in that time frame, even with reduced performance, I believe they would have reduced aircraft losses and reduced air crew illness and injury (such as frostbite). 

I also have little doubt that they would have suffered heavier losses than B-29s did in the CBI and PTO historically. 

Not sure if they would have proved more effective at bombing, but certainly there would have been more tonnage dropped in the target area.

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## tomo pauk (Apr 14, 2014)

That about wraps it up.


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## wuzak (Apr 14, 2014)

GregP said:


> I DO know the B-29 was very effective and hard hitting, with the heaviest normal bomb load of the war by a bomber in large scale production.



A normal bomb load for a Lancaster was 14,000lbs. What was the normal bomb load for a B-29? I don't think it was the maximum 20,000lb, because range suffered with that load.




GregP said:


> Don't even tell me about Grand Slams ... they were never a "normal" bomb load and the Lancasters that carried them were structurally in dangerous waters. It was done out of necessity, not with any regularity. They dropped a total of 42 Grand Slams in the entire war, less than .03% of Lancaster sorties.



Let's put big bombs into perspective.

Sure the Grand Slam and Tallboy were late comers and statistically insignificant in the number of missions for which they were used.

Let us look at the big bombs the USAAF used - 1600lb, 2000lb, 4000lb and 4500lb.

The USAAF dropped ~66,300 bombs of over 1000lb nominal weight. The RAF dropped 93,000 4000lb HC and 24,000 4000lb MC bombs. They dropped relatively few 2000lb bombs, because the one they had was an older design with low charge ratio and they did not develop a replacement. 

Of the bombs over 2000lb, the USAAF dropped ~1400. 879 Tallboys were used by the RAF, 835 of those being dropped at a target. In other words, thenumber of Tallboys the RAF dropped was ~60% of the number of 4000 and 4500lb bombs the USAAF dropped.


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## pbehn (Apr 14, 2014)

wuzak said:


> Getting a reliable B-29 into production earlier may have allowed the USAAF to deploy them to where they were needed when they were needed most. ie in the ETO in late 1943/early 1944.
> 
> Had they been deployed in that time frame, even with reduced performance, I believe they would have reduced aircraft losses and reduced air crew illness and injury (such as frostbite).
> 
> ...



The losses suffered in the PTO were just to say sustainable, the B29 was a leap forward in cost, complexity and training. What were termed acceptable losses with B17s and B24s were not acceptable with a B29. The successful raids on Japan were low level incendiary raids and of course the A bomb. Dropping conventional bombs from high altitude wasnt very successful at all. The B29 in Europe in 1943/44 may well have taken a hammering with the cost out of all proportion to the damage inflicted.

Apart from the cost in lives and cost of training, from Wiki "In 1945, a B-29 bomber cost $782,000. It cost $32,000 to upgrade an aircraft to Silverplate configuration, so the total cost of a Silverplate bomber was $814,000, about $10.7 million in 2014 dollars. "


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## GregP (Apr 14, 2014)

Hi Wuzak,

I keep records of the data I find. In a book titled, “Combat Aircraft (31) Lancaster Squadrons 1942 – 1942” by John Lake there is a table of data for the war. It shows the Lancaster flew 156,192 sorties of which 148,403 were bombing sorties. In those sorties the Lancaster dropped 681,645 short tons of bombs. A “short ton” Is 2,000 pounds. They suffered 3,832 combat losses. That works out to 4.6 short tones per sortie per Lancaster, or 9,186 pounds per average sortie with a loss rate of 0.0258 per bombing sortie. Hardly 14,000 pounds over the war’s sorties.

The USAAF Statistical Digest says the B-29 flew 31,387 sorties against Japan and dropped 159,676 short tons on the sorties with 414 lost in combat. That works out to 5.1 short tons per sortie per B-29, or 10,175 pounds per average sortie with a loss rate of 0.0132 per sortie. Hardly 20,000 pounds, but more than the Lancaster’s average.

We could argue capabilities until we are blue in the face, but the B-29 carried a bit more bomb load on average, had about half the loss rate, and was easily 100 mph faster when pushed. It also could carry almost 50% more than the Lancaster on normal ops if range didn't dictate less bombs an more fuel. Over an ocean, that didn't prove to be the case. Over Europe, if it had been deployed there, maybe ... maybe not ... depends on a lot of factors that I won't even try to summarize.

These numbers say nothing about the environment of the operations, the opposition expected and encountered or anything else subjective. They are merely the averages for the ops flown. Since no two authors can seem to ever agree on anything unless one quotes the other, I’m sure other numbers can be found floating about. They’ll still show the B-29’s carrying more on average with a lower loss rate than the Lancaster. The B-29 could have averaged quite a bit more bomb load if it was only going between London and Berlin, but they operated where they did and flew the mission lengths required of them, at the time.

This is just wartime performance on average, nothing more. It doesn't take into account when the bomb load was less because they ran out of bombs or any other operational difficulties.


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## FLYBOYJ (Apr 14, 2014)

wuzak said:


> A normal bomb load for a Lancaster was 14,000lbs. What was the normal bomb load for a B-29? I don't think it was the maximum 20,000lb, because range suffered with that load.



3250 miles at 25,000 feet (7620 m) with 5000 lb (2270 kg) bomb load
4100 miles at 25,000 feet (7620 m) with 5000 lb (2270 kg) bomb load and auxiliary fuel tank
4700 miles (7600 km) max 

The Pacific War Online Encyclopedia: B-29 Superfortress, U.S. Heavy Bomber


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## GrauGeist (Apr 14, 2014)

The B-29 may have had problems with it's engines early on, but it was also a new, highly advanced system that raised the bar on heavy bombers/strategic bombers.

As with any new system, there will be a debugging period where problems will be addressed and corrected. They are also going to be expensive, any new system is.

The B-52 had it's initial setbacks and so did the B-2...and so will the next system and the next and the next...

Remember, the Martin B-10 was one of the most advanced bombers for it's time, and people complained about spending money on it even though it raised the bar on bomber design by quite a bit.


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## pbehn (Apr 14, 2014)

The biggest problem for the B 29 was the "jet streams" which meant regardless of the gun sight you could miss by miles even if you could see the target which frequently you couldn't. Apart from the A Bomb which ended the war and night time fire storm raids its best use was probably mining sea lanes and ports. Fantastic airplane but ranged against the wrong enemy, although I believe it was first conceived when it was thought Germany would control Europe. It was pointless attacking the steel industry in Japan, they had no raw materials (ore coal etc) It was pointless attacking the shipbuilding industry it had no steel to make ships with, and for the oil industry the refineries were in many cases stood idle for want of crude. That said it was a great aircraft.

In Europe the B 29 would have been well above most Flak but it was still vulnerable to fighters.

Here is a question guys. The B 29 had a very sophisticated defence system with "computer" controlled firing/targeting was this proven to be more effective than the conventional defence of the B17 B24?


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## GregP (Apr 14, 2014)

In practice it was very effective because the B-29's would climb higher than necessary so they could attack from a shallow dive and be at the correct altitude over target at high speed, on the order of 320+ mph. That means that most, but not all, attacks on a B-29 were from the rear ... with radar-aimed tail guns. 

There was almost no way a typical Japanese fighter could make a pass and then circle around to attack a second time. If he made a head-on pass, by the time he turned 180° the B-29 was already 2 - 3 or more miles ahead and the closing speed and extra fuel wasn't sufficient for a tail chase. There were very few beam attacks on B-29's over Japan.

Had the B-29 been deployed over Europe, things might have been a bit tougher since Europe was a high-altitude war at higher speeds. But it never was deployed there except as a visiting decoy. There was at least one B-29 that made a circuit of the UK bases, probably to cause concern in Germany.


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## pbehn (Apr 14, 2014)

GregP said:


> Had the B-29 been deployed over Europe, things might have been a bit tougher since Europe was a high-altitude war at higher speeds. But it never was deployed there except as a visiting decoy. There was at least one B-29 that made a circuit of the UK bases, probably to cause concern in Germany.


I believe it was being evaluated and they used the opportunity for propaganda, The RAF did consider it for night bombing, maybe if losses to flak and nightfighters became too high in a protracted war.


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## FLYBOYJ (Apr 14, 2014)

pbehn said:


> Here is a question guys. The B 29 had a very sophisticated defence system with "computer" controlled firing/targeting was this proven to be more effective than the conventional defence of the B17 B24?



I believe it was - It took the gunners away from the actual weapon (no fumes or gun recoil vibration) and the turrents could be shared between gun positions.


_View: https://www.youtube.com/watch?v=UiT5QLRHl0Q_


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## pbehn (Apr 14, 2014)

Thanks GregP and Flyboy, looking at that video I am sure it worked well with a few hostiles, but facing a massed attack would the people targetting know they were targetting the same plane. From what Greg said if most attacks were from the rear maybe it was all overkill.


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## gjs238 (Apr 14, 2014)

*Re: R-3350*
It seems that unless Curtiss-Wright is infused with vast sums of support (money, engineering staff, etc) it will not be able to properly develop the R-3350 in a more reasonable timeline without sacrificing development of the R-2600.

Curtiss-Wright was already plodding through numerous projects and is criticized for not better developing the P-40, or a successor for the same.

Is this mismanagement, or did they really need support?

If the answer is that C-W could under no circumstances properly develop the R-2600 and R-3350 simultaneously, then we have a choice to make. Which one gets priority.
Historically the R-2600 received priority.

If we allow the R-2600 to have priority, let's substitute V-3420's for the R-3350's.
If we give the R-3350's priority, what do we replace the R-2600's with?

*V-3420*
Much of the same can be asked of Allison.
We know historically that Allison was unable to properly develop the V-3420 in a reasonable time.
And we know their record with 2-stage supercharging of the V-1710.
If infused with vast sums of support (money, engineering staff, etc) would it be able to properly develop the V-3420 to power the B-29 or B-32 in a more timely and reliable fashion?

*Other*
If neither Allison or C-W can pull this off, what other options are there to the historical timeline?
R-2800's have been mentioned. But that seems to entail a smaller plane.


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## GregP (Apr 14, 2014)

If you have to have a defense in a bomber, I want all the overkill I can get!

I was wondering how the radar-aimed guns decided whether or not the target was friendly or hostile. I'd HATE to be in the middle of the formation and have my IFF go on the blink or get shot out in an attack ... IF they used IFF's in WWII to distinguish targets from friendlies ... that is. 

I never checked into that before ...

I'm thinking it was optical and the gunner could SEE his target reflected in the sight.


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## pbehn (Apr 15, 2014)

GregP said:


> If you have to have a defense in a bomber, I want all the overkill I can get!
> 
> I was wondering how the radar-aimed guns decided whether or not the target was friendly or hostile. I'd HATE to be in the middle of the formation and have my IFF go on the blink or get shot out in an attack ... IF they used IFF's in WWII to distinguish targets from friendlies ... that is.
> 
> ...



I was thinking along the lines of ditching all but the tail gun and flying higher and faster? As I see the video, the radar is for range, one of the inputs into the "computer" but for some reason it wont play anymore on this laptop here. 

I would think from the footage I have seen of raids over Europe it would be easy for the guys targeting the guns to select completely different planes, just a thought.


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## gjs238 (Apr 15, 2014)

US presidents, prone to hoof in mouth syndrome, often do not commit US military forces in the most efficient or effective way.
As part of the B-29 reset, might we deploy to the ETO instead of Asia?
After all, the agreed upon grand strategy was Germany first: https://en.wikipedia.org/wiki/Europe_first

The distances covered would be less, and the logistics of operating from the UK significantly better (B-29's would not be needed to ferry their own supplies over the highest mountain range on the planet.)

Flying higher and faster, I can only imagine Axis flak and fighters would be less effective.


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## FLYBOYJ (Apr 15, 2014)

As far as the B-29 in the ETO - From Wiki...

_"Originally, the Army Air Forces intended the B-32 as a "fallback" design to be used only if the B-29 program fell significantly behind in its development schedule. As development of the B-32 became seriously delayed this plan became unnecessary due to the success of the B-29. *Initial plans to use the B-32 to supplement the B-29 in re-equipping B-17 and B-24 groups before redeployment of the Eighth and Fifteenth Air Forces to the Pacific were stymied when only five production models had been delivered by the end of 1944, by which time full B-29 operations were underway in the Twentieth Air Force."*_


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## Shortround6 (Apr 16, 2014)

A couple of points on engines.

1. Aircraft diesels Were great in theory but nobody really came up with _good_ones. Ones that worked yes, ones that could compete with engines running on 80-87 octane gas (at least in some areas) yes. 
Diesels used higher peak pressures inside the cylinders and had to be built heavier than an _equivalent_ spark ignition engine. Once the Gas engines went to 100 octane and higher the power to weight ratio of the diesels got worse in comparison. High powered diesels would take even longer to develop than high powered gas engines. ( please look at how long it has take to come up with high powered diesel car engines) 
2. The early R-3350 was quite different than the later WWII R-3350 and the Post-war R-3350s were changed quite a bit again. The R-3350 engines used in the B-29 used quite a bit of knowledge that Wright had learned working on the R-2600s so while slowing or stopping work on the R-2600 to work on the 1st R-3350 design might ave speeding things up a bit it would not have changed things by years as Wright had to learn _somehow_ all the stuff they wound up using on both engines. For example the early engines of both types didn't use the harmonic balancers that the later engines did and there was no room inside the crankcase on the early engines for them, later engines used crankcases several inches longer.
I am not sure when Wright shifted to the "W" style sheet metal fins on the R-3350.
3. WHile the Russians did power the TU-4 with 18 cylinder radial engines it was their *4th* attempt at an 18 cylinder Wright based radial and the first 3 were less than stellar successes. Not only no hope there but rather points out that an 18 cylinder is not quite as simple to make as some people think even if you have a working 14 cylinder engine using the same cylinders. 
4. in the early years (1939/40/41) _before_ 100/130 fuel the Wrights extra displacement would be seen as an advantage as neither the R-2800 or R-3350 could use the higher boost levels. Also please remember that the late war 2800hp R-2800s were basically a whole new engine with new methods of manufacture and much improved cooling ability (less cooling drag for same power), While P&W _started_ work on this version in 1940 it didn't see service until late 1944 and planners would have had to have been fairly optimistic
to _plan_ on this engine powering a major bomber program back in 1941/42 when factory allocations were being made.

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## fastmongrel (Apr 16, 2014)

Napier spent a lot of time and money postwar trying to get the Nomad diesel working and even after 9 years with the best of will it was a dull engine beaten by a Wright Turbo Compounf R3350 in power and economy terms.

Napier Nomad - Wikipedia, the free encyclopedia


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## Greyman (Apr 16, 2014)

GregP said:


> I was wondering how the radar-aimed guns decided whether or not the target was friendly or hostile.



Bomber Command's AGLT ('Village Inn') used an infra-red IFF system to discern friend from foe.


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## BiffF15 (Apr 16, 2014)

GregP said:


> I was wondering how the radar-aimed guns decided whether or not the target was friendly or hostile.
> I'm thinking it was optical and the gunner could SEE his target reflected in the sight.



GregP,

I'm thinking you are right (optical sight A.K.A. Mk 1 eyeball). I do remembering reading somewhere that the P-61s shot down a friendly or two that weren't squawking friendly on their return from runs over Japan (I assume the Widow had an IFF interogator on board). The Japanese were evidently following the bombers back to Okinawa.

Cheers,
Biff


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## Reegor (Apr 21, 2014)

GregP said:


> In practice it was very effective because the B-29's would climb higher than necessary so they could attack from a shallow dive and be at the correct altitude over target at high speed, on the order of 320+ mph. That means that most, but not all, attacks on a B-29 were from the rear ... with radar-aimed tail guns.
> 
> There was almost no way a typical Japanese fighter could make a pass and then circle around to attack a second time. If he made a head-on pass, by the time he turned 180° the B-29 was already 2 - 3 or more miles ahead and the closing speed and extra fuel wasn't sufficient for a tail chase. There were very few beam attacks on B-29's over Japan.
> 
> Had the B-29 been deployed over Europe, things might have been a bit tougher since Europe was a high-altitude war at higher speeds. But it never was deployed there except as a visiting decoy. There was at least one B-29 that made a circuit of the UK bases, probably to cause concern in Germany.



Yes, this method of descending high-altitude attack by B-29s made life even harder for the Japanese defenders. (It also contributed to the "too fast" problem caused by the jet stream, mentioned by pbehn.) Of course the B-29 high-altitude attacks ultimately contributed almost nothing to ending the war, due to lack of suitable targets, inability to bomb accurately from that altitude, the fact that the factories being bombed had no raw materials due to effective blockade of Japan, etc. The B-29s became useful only when LeMay changed to low altitude fire bombing. 

In Europe, German pilots eventually used head-on attacks as their most effective, due to high closing speed and relatively weaker forward armament in B-17s. The same would have been true with B-29s in Europe. A problem with head-on attacks, though, was that they required considerable advance warning to get into position ahead of the bombers. That warning was often not provided by the German zone-control air defense system. Furthermore, by 1944, German pilots were so inexperienced that most of them had difficulty to "join up" for a second attack, once the first pass was over. I have to think that higher speed of B-29s would have made all of these problems more serious for the defenders. (Wikipedia lists the cruise speeds as 182 knots for B-17, 190 knots for B-29, but this does not match what I remember from reading memoirs. Of course actual cruise speed depends on load and altitude. )


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## GrauGeist (Apr 21, 2014)

Wait...what??

If you do some research, you'll find that the Japanese were quite capable of employing head on attacks against the B-29 over Japan.
The Germans were using the head on attacks successfully to the point that the chin turret was introduced (late B-17F onward) to try and ward off such attacks.

In 1944, the attacks on the bombers were anything but amateur attempts and multiple passes were the norm. Perhaps read some B-17 crew memoirs on how savage the attacks were, by Luftwaffe interceptors...or perhaps read some Luftwaffe pilot memoirs on how they employed their attacks.

Any inexperienced pilots were told to stick the Rotte leader and follow through with them...they weren't allowed to just wander around up there.


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## GregP (Apr 21, 2014)

Over Japan the B-29's were not operating at cruise speed. They cruised to the target area and accelerated to "attack speed" which was usually between 290 and 335 mph or more depending on the shallow dive. Once out of local fighter range, they decelerated back to cruise speed to the flight home.

The B-17's in Europe never, apparently, tried that tactic. Perhaps the smaller B-29 formation made it possible. It would have been very dangerous to try coordinating a uniform acceleration and dive for several hundred or more bombers.


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## FLYBOYJ (Apr 21, 2014)

GregP said:


> Over Japan the B-29's were not operating at cruise speed. *They cruised to the target area and accelerated to "attack speed" which was usually between 290 and 335 mph or more depending on the shallow dive.* Once out of local fighter range, they decelerated back to cruise speed to the flight home.
> 
> The B-17's in Europe never, apparently, tried that tactic. Perhaps the smaller B-29 formation made it possible. It would have been very dangerous to try coordinating a uniform acceleration and dive for several hundred or more bombers.


I think that depends on the mission. It they were bombing at altitude using a bombsight they were flying about 210 mph.

http://www.ww2aircraft.net/forum/ot...ngineering-flight-book-8691-2.html#post137292


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## GregP (Apr 21, 2014)

Just going from B-29 vet's given at the museum. If we have any of them, it's usually when the subject is "Long Range Escorts." Mostly we hear from P-51 or P-47 pilots, but occasionally we hear from a bomber guy.

It is possible they did both, depending on the actual target. I wouldn't argue too hard either way.


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## gjs238 (Apr 21, 2014)

GregP said:


> Over Japan the B-29's were not operating at cruise speed. They cruised to the target area and accelerated to "attack speed" which was usually between 290 and 335 mph or more depending on the shallow dive. Once out of local fighter range, they decelerated back to cruise speed to the flight home.
> 
> The B-17's in Europe never, apparently, tried that tactic. Perhaps the smaller B-29 formation made it possible. It would have been very dangerous to try coordinating a uniform acceleration and dive for several hundred or more bombers.



Were the B-29's accelerating to attack speed, or were they backing off to prevent engine fires?


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## GregP (Apr 21, 2014)

They were not backing off to prevent engine fires. Don't be a spokesman for disinformation. The R-3350's had issues but. again, I might remind you the B-29 had the *lowest combat loss rate of ANY heavy bomber of WWII*. If that's a dangerous engine, I'll fly behind it every time regardless of engines, if given the choice of the B-29 or any other heavy bomber.

If I had to choose one and only one bomber to fly, I'd take Douglas A-26's every time.

Gis238, please don't troll for an argument. If you attend one the talks given by the vets and ask that kind of question, they'll eat you alive and you'll be asked to leave if you do it twice. State your opinion by all means if you can back it up with facts, but it's tough to say something was a death trap when it flew 31,000+ sorties with the lowest loss rate in the USAAF for it's class of aircraft, don't you think?

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## gjs238 (Apr 21, 2014)

It was a simple question.


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## gjs238 (Apr 21, 2014)

GregP said:


> but it's tough to say something was a death trap when it flew 31,000+ sorties with the lowest loss rate in the USAAF for it's class of aircraft, don't you think?



In the later part of the war, as engine issues were worked out (but not eliminated), and high altitude flights were abandoned, the performance certainly improved, in turn improving the statistics you quote.

What are the stats for the earlier high altitude long duration flights?

You have already suggested that a V-3420 powered B-29 might have improved on this record and I agreed that that may be a worthwhile alternative to explore.



GregP said:


> The B-29 could certainly have been improved and it was covered a ways back. The R-3350 was developed and ran very early. Then it languished for 5+ years while they developed the R-2600. If the main customer had asked Wright to concentrate on the development of the R-3550, it would have been ready 5 years sooner, with the attendant benefits of a more mature engine sooner. But that is a what-if and has no bearing on what happened.
> 
> You couldn't just hang 6 R-2800's on it without considerable redesign, probably more span, probably requiring more tail and possibly more length. That would waste enormous effort and resources, all for nothing. The B-17 and B-24 were doing the job we needed done and the development of the B-29 was pretty much tied to the development of the R-3350 or other suitable large piston engine ... not the R-2800.
> 
> ...


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## GrauGeist (Apr 21, 2014)

gjs238 said:


> In the later part of the war, as engine issues were worked out (but not eliminated), *and high altitude flights were abandoned*, the performance certainly improved, in turn improving the statistics you quote.


Not abandoned, limited. Because of errant air currents over the Japanese islands, causing targeting issues.

The B-29 was not the PoS that some people are making it out to be and if it was such a problematic failure, the Japanese sure didn't think so. They spent alot of time and materials to build interceptors in the hopes of stopping it.

The B-29 was a new innovation in technology and anything new always has bugs to be worked out. There rarely is a door-buster in technology that goes from the drawing board to hands-on without some sort of issue being encountered. Even the first Space Shuttle, the Enterprise, was found to have a fatal flaw in the wingroot system that caused the wings to flex under stress. That discovery was made only after it was released from the 747 for it's maiden flight. Had it gone to space, it would have become a supersonic lawndart on re-entry.

So the point here is, yes, the B-29 had problems. Those problems were corrected as time went by, but in the mean time, it's service was what was needed, when it was needed and it got the job done.


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## FLYBOYJ (Apr 21, 2014)

gjs238 said:


> In the later part of the war, as engine issues were worked out (but not eliminated), and high altitude flights were abandoned, the performance certainly improved, in turn improving the statistics you quote.
> 
> What are the stats for the *earlier* high altitude long duration flights?



How about "later"? Like Korea?

B-29 in Korean War


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## gjs238 (Apr 21, 2014)

The mission here men, is how to help the WWII effort. How can we get the aircraft fielded sooner and improve the early performance?
One suggestion was a different engine.
Another suggestion was two more engines.
Another suggestion was improving development of the historical engine.
All, I am sure, could be interesting discussions, but we keep getting off onto defensive lines of thought.


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## GrauGeist (Apr 21, 2014)

gjs238 said:


> The mission here men, is how to help the WWII effort. How can *we get the aircraft fielded sooner and improve the early performance?*


You couldn't...there was just too much to be worked out. So much so, that the military started looking at alternatives in case it didn't work out.
The XB-19 program was in the works and first flew in '41. It had used both the Allison V-3420 and the Wright R-3350 engines.
The XB-39 was an Allison engined B-29 alternative and actually proved to be faster and higher flying than the Radial powered B-29. The problem here, is that it would be late to the game *unless* they had designed the B-29 with Allison V-3420-17 from the beginning. The V-3420-17 was available well before the U.S. got involved in the war and could have easily been incorporated into the design.
And of course, there was the B-32 project that started shortly after the B-29 began development. But it also called for R-3350s, so we're back to square "A".



gjs238 said:


> One suggestion was a different engine.


The P&W R-4360 Wasp Major was initially rated at 3,000 hp...but it was in development until '44. Until then, the R-2600 was a close competitor. There's other Radials available, but you need to horsepower to get this monster in the air under load and then move it a great distance.



gjs238 said:


> Another suggestion was two more engines.


You can't just hang extra engines on something without extensive rework. Alot of consideration has to be taken for engine placement and support. You also need to add extra fuel tanks to feed those two new engines. and the list goes on.
Probably plenty of room for the additional oil tanks, though. 



gjs238 said:


> Another suggestion was improving development of the historical engine.


They were working on the R-3350 as best as they could, especially with the military breathing down their neck. (imagine: "are we there yet? Are we there yet? Are we there yet?")


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## GregP (Apr 22, 2014)

If that was s simple question, please think about them going forward. When someone says it's accelerating and you asked if they weren't really backing off to avoid death, it comes across as very sarcastic. Since I have done that very thing in the past unintentionally (everyone laugh here ...), let's move on.

The B-29 performed VERY well. Here is a pic of the XB-39, basically a B-29 with the Allison V-3420 as the powerplant.







If you want to start improvement, why not start with the bombers that needed it the most? The B-17 and B-24 could have been improved, too. They DID try a B-17 with Allisons, the XB-38 ... it was the fastest B-17 on record. Here's a pic:






They didn't elect to produce it or even continue with tests, for some reason.

Here's a B-24 with a B-17 nose section grafted on: 






They didn't proceed with that either, though it certainly LOOKED better than a standard B-24. I haven't seen a B-24 with alternate powerplants or an alternate airfoil, both of which it could have used. The PB4Y-2 was a single tail version, without other improvement and the side turrets were ludicrous. Other than the planes already mentioned (B-17, B-24, B-29, B-38, B-39) I can't think of any US heavy prototypes that would have helped out.

I like the XB-42 / 43, but it was a medium bomber, as was the "improved" B-25, the North American XB-28. I can't think of anymore heavy bombers we worked on during WWII that made serve in WWII. The XB-35 didn't fly until after the war and was politically killed. The XB-15 and XB-19 were pre-WWII and were not selected for production.

I'm out of candidates, but firmly believe the B-29 was everything it needed to be, albeit a few years late due to the R-3350 that was neglected for 5 years by Wright. If they had not done that, the B-29 would have been a very major player in the war. But they HAD their chance with the V-3420 version and turned it down, probably over drinks at a golf course by people who weren't really familiar with the Allison, but who were in a position to shoot it down yet again despite very promising test results.

Politics was and IS alive and well, even today. Think of the disaster called the F-35. Why in hell we are still throwing money at it I'll never know, but we are. If you can't successfully make it combat worthy with a run of 100+ aircraft. I suggest you cut your losses and move on. But we certainly aren't, are we? And if you can't develop it in 25 years, you don't need it.


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## FLYBOYJ (Apr 22, 2014)

GregP said:


> Politics was and IS alive and well, even today. Think of the disaster called the F-35. Why in hell we are still throwing money at it I'll never know, but we are. If you can't successfully make it combat worthy with a run of 100+ aircraft. I suggest you cut your losses and move on. But we certainly aren't, are we? And if you can't develop it in 25 years, you don't need it.


Greg, once again you make unwarranted and unsubstantiated attacks on the F-35 while it's still under development. Earlier in this thread you didn't appreciate the comment of gjs, now I'm calling BS on this as you're crossing the political line here and really clouding this thread. I don't want to shut this thread down so I suggest sticking to topic and keeping F-35 discussions to specific threads where you could show *actual proof *of it's downfall or success. As you said earlier "please don't troll for an argument," I hope I'm clear on this!!!!


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## Shortround6 (Apr 22, 2014)

In a lot of cases timing is everything. The B-19 taught Douglas ( and by extension, the US aero industry, The Government paid for the design data and shared it) a lot about large aircraft structures and other problems but it took so long to complete that it was out of date when it first flew. Contracts for the B-35 and B-36 being issued before the B-19 first flew. With R-3350 engines it had a top speed of 224mph. While it had range and bomb load it didn't have enough performance to hope to survive in hostile skys. 

In order to get the numbers of bombers desired ( and the engines to power them) decisions had to made on which designs to mass produce around two years before squadron service. Design work started on the B-24 in 1938. Early versions with out turbo superchargers failed to meet specified speed. First US combat use of fully combat capable B-24s was in June of 1942 by 13 planes. Mucking about with "improved" aircraft in 1941-42 is going to delay the onset of the bombing campaign by months (or several seasons) minimum. Switching a factory from one bomber type to another (or a substantial modified version) could result in a loss of production of hundreds of air-frames. The US might be able to afford such a loss in 1944 but by then it is almost too late to matter, Loosing that number of air-frames in 1942 or early 1943 is something else. And to be switching production lines in 1942-43 means design work needed to start back in 1940 (4 engine bombers need more time to design than single engine fighters).


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## pbehn (Apr 22, 2014)

The soviet Tu 4 used a Russian development of the Wright R-1820, maybe that would have been an option.

from wiki
The Soviet engine, the Shvetsov ASh-73 was a development of the Wright R-1820 but was not otherwise related to the B-29s Wright R-3350.[


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## Shortround6 (Apr 22, 2014)

We have been over this before. the ASh-73 was a development of the R-1820 in the _same_ way that the R-3350 was a development of the R-1820. they were evolved in parallel with the ASh-73 being later in timing, much later. Production did not begin until 1947 FlyboyJ has provided this chart before but here it is again. 






Please note that the 18 cylinder engines M-70, M-71 and M-72 were pretty much failures. Trying to substitute a metric 18 cylinder failure for an SAE 18 cylinder failure ( in early versions) isn't going to solve or speed up anything for the US forces.

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## gjs238 (Apr 22, 2014)

I'm not suggesting changes during production that would create even more delays.
What I am suggesting are design changes prior to production that we can make with the benefit of hindsight.

At the genesis of the B-29 folks could not have known how extended development of the R-3350 was going to be.
Unless we can come up with a reasonable plan to get the R-3350 ironed out sooner, it seems that perhaps the XB-39 with the Allison V-3420, may have been the best solution.
As Greg pointed out earlier, it was a "low risk" design.

Mass production of the V-3420 in quantity exceeding B-29 demand could have led to other uses of the V-3420, as occurred historically with the R-3350.

Earlier fielding of the B-29 and more reliable early fielding of the B-29 could provide some interesting speculation.
Perhaps the B-29/B-32 would have appeared over Europe.
Perhaps the bombing campaign against Japan would have gone differently.


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## tomo pauk (Apr 22, 2014)

Was the M-71 really a failure?


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## Balljoint (Apr 22, 2014)

GregP said:


> They were not backing off to prevent engine fires. Don't be a spokesman for disinformation. The R-3350's had issues but. again, I might remind you the B-29 had the *lowest combat loss rate of ANY heavy bomber of WWII*. If that's a dangerous engine, I'll fly behind it every time regardless of engines, if given the choice of the B-29 or any other heavy bomber.
> 
> If I had to choose one and only one bomber to fly, I'd take Douglas A-26's every time.
> 
> Gis238, please don't troll for an argument. If you attend one the talks given by the vets and ask that kind of question, they'll eat you alive and you'll be asked to leave if you do it twice. State your opinion by all means if you can back it up with facts, but it's tough to say something was a death trap when it flew 31,000+ sorties with the lowest loss rate in the USAAF for it's class of aircraft, don't you think?




I think the B-29 was a great machine for its time. However, the engine nacelles were a bit tight and with a poor firewall, engine fires got to the magnesium engine mounts rather directly. Being at or over gross often in the Tinian heat, the 29 had a serious weakness in the way it was operated.

During a conversation with the Wright theater engineer he spoke of an unusual loss rate among the B-29s flying the Hump with cargo. By bumming rides in the jump seat he learned that, apparently from boredom, the pilots were competing to have the lowest fuel consumption. Apparently they were using Lindbergh’s P-38 technique which the B-29 didn’t forgive.

The plane wasn’t bad but it needed careful handling and was a bit marginal when the limits were pushed as often the case at Tinian. Once at altitude and speed and having burned off some fuel it was just another plane,

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## fastmongrel (Apr 22, 2014)

Was the V3420 a low risk design. Almost everyone else who tried doubling up engines had problems when they went from hand made prototypes to line built engines.


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## GrauGeist (Apr 22, 2014)

pbehn said:


> The soviet Tu 4 used a Russian development of the Wright R-1820, maybe that would have been an option.


The TU-4 was a reverse engineered B-29, so it required the development and deployment by the U.S. before the Russians were able to take interred examples and create the TU-4 and it's native powerplants.


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## FLYBOYJ (Apr 22, 2014)

Balljoint said:


> During a conversation with the Wright theater engineer he spoke of an unusual loss rate among the B-29s flying the Hump with cargo. By bumming rides in the jump seat he learned that, apparently from boredom, the pilots were competing to have the lowest fuel consumption. Apparently they were using Lindbergh’s P-38 technique which the B-29 didn’t forgive.


Linbergh's procedure called for operating lower RPMs at higher manifold settings, not to exceed what the manufacturer specifies, doing this while you set the mixture to "lean of peak." This wasn't voodo magic and I would guess that the FE's manual had mixture setting procedures that specified this. I would also think that if the pilot was exceeding limits the FE would be punching the crap out of him!


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## Shortround6 (Apr 22, 2014)

Linbergh's procedure was pretty much the same as Tony Levier's which means it was pretty much what both Lockheed and Allison recommended for P-38s ( Army instructors didn't ?). It was also pretty much standard for Merlins and most other aircraft engines that had pilot or FE controllable mixture settings.


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## GregP (Apr 22, 2014)

Hi Flyboy,

You are very clear. I didn't think not liking it was political, but I understand you apparently do. 

So I'll pipe down about not liking it in here except in F-35 threads.

Is that OK?

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## Shortround6 (Apr 22, 2014)

Russians were working on the M-71 engine in 1939 with a few prototypes built in 1939 and a few the following the year, it did NOT pass it's state tests until the fall of 1942 and was only flown in 4 types of prototype aircraft. The I-185 was flying with it in the Spring of 1942 and performance was such that series production was planed. Series production of the I-185 was canceled in mid 1943 due to continued unreliability of the M-71 engine and the need to use the M-82 (the only alternative) in the LA-5. 

The M-72 was pretty much a two speed supercharged M-71 and was due to start production in the 3rd quarter of 1945 ( a little late for the B-29) but was superseded by the Ash-73. Please note that ALL these engines were from the same design team. Work started on teh Ash-73 in 1944 but prototypes were not built until 1945/46 with a few engines using some American components. State tests were started in Aug of 1946 but not completed until 1948.


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## GregP (Apr 22, 2014)

Was the V-3420 a low-risk design?

The V-1710 doesn't leak much oil. It weeps a small bit, like any large V-12, but rather less than most other engines. The double DBs tended to leak more because they were inverted V-12's, not upright V-12's. In inverted engines, any potential leaks usually eventually DO leak. More oil leaks lead to more oil in the nacelle or in the V between the two crankcases that is ready to ignite.

I can't say definitely, but the only V-3420 I have ever seen run was absolutely dry after the run. That being said the run was not more than 8 minutes or so, and you might expect that. But it certainly wasn't leaking from anywhere unexpected.

On the Allison, the main sources of oil leaks are a few drops coming from the prop shaft seal, some very small occasional leaks from the tachometer drive, maybe a few leaks from the valve covers,. and maybe a trail or two from where the top and bottom engine cases join. The engine case leaks usually stop after 1 - 3 hours of running, which we do on a test stand. Altogether not much in the way of leaks, usually a few drops and maybe a very small oil trail that wipes off easily after flight. 

When Joe Yancey builds his engines, we usually see a few leaks on the first run, wipe them down during cool down and tighten a few things and almost nothing after that ... maybe a few drops. It certainly leaks much less than any radial I have ever tried to wipe down, including a Russian M-14P in a Yak-52. So I THINK it might be a good candidate for the double engine, if ever there was one. 

But only time and experience could tell us.

There is no record of the XB-39 having issue with the V-3420, but since the R-3350's were performing well in combat, it also didn't make sense to convert to the V-3420, so they dropped it.

The only real trouble with Allisons in bomber development I know of was the XB-38, which was the Allison-powered B-17. Apparently the Allison V-1710's installed in it had intake leaks and they had to correct that at least once or twice. On the last flight the left inboard engine caught fire and they bailed out. Allisons mostly do not catch fire and the P-38, P-39. and P-40 didn't have issues with that event. So it makes we wonder of they had people working on the XB-38 at Vega who were familiar with the Allison at all. Unfamiliarity opens all sorts of opportunities for problems.

Bringing in Joe Yancey again, when he assembles an engine, the intake seals get a lot of attention. If they are cracked they cannot be used. He has never shipped an Allison with intake leaks, but I have seen one that had a leak and we fixed it. You could tell by the color of the inside of the exhaust pipe that the mixture was different in three cylinders on the left bank, so we easily found the leaking intake seal. The pipes cleaned up and showed the same color as the rest on the next run.

In the end, they elected not to try that alternative, but it was there for the taking if the R-3350 had stumbled enough to warrant it.


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## tomo pauk (Apr 22, 2014)

Thanks. That is from Kotelnikov, I presume? 
The M-71 was already featuring the 2-speed S/C, going from the table posted here (can be translated)? Power was 1798 or 1673 CV, at FTH of 2250 and 5025 m respectively.


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## FLYBOYJ (Apr 22, 2014)

Shortround6 said:


> Linbergh's procedure was pretty much the same as Tony Levier's which means it was pretty much what both Lockheed and Allison recommended for P-38s ( Army instructors didn't ?). It was also pretty much standard for Merlins and most other aircraft engines that had pilot or FE controllable mixture settings.


WW2 pilots were so ingrained about over boosting that I think some sections of the POH (especially performance charts) were ignored.

In many aircraft those throttles BELONG to the FE, the pilot just "steers the plane."


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## pbehn (Apr 22, 2014)

GrauGeist said:


> The TU-4 was a reverse engineered B-29, so it required the development and deployment by the U.S. before the Russians were able to take interred examples and create the TU-4 and it's native powerplants.



Yes I know but the engine was a reverse engineered engine from an earlier model, I was just suggesting if the Russians could fly a B29 copy in 1947 maybe the USA could have done it much earlier after all from wiki

The R-1820 Cyclone 9 represented a further development of the Wright P-2 engine dating back to 1925. Featuring a greater displacement and a host of improvements, the R-1820 entered production in 1931. The engine remained in production well into the 1950s.


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## Shortround6 (Apr 22, 2014)

pbehn said:


> Yes I know but the engine was a reverse engineered engine from an earlier model, I was just suggesting if the Russians could fly a B29 copy in 1947 maybe the USA could have done it much earlier after all from wiki



The Russian engine was NOT reverse engineered. Using the same (or similar) starting point it took the Russians until 1947/48 to develop a production/serviceable engine comparable to the R-3350 which was in service 2-3 years earlier.



> The R-1820 Cyclone 9 represented a further development of the Wright P-2 engine dating back to 1925. Featuring a greater displacement and a host of improvements, the R-1820 entered production in 1931. The engine remained in production well into the 1950s.



Not quite right but a common misconception. The Wright Cyclone 9 started as a 1750 cu/in modification (longer stroke) to the 1654 cu/in P-2 (only 14 built) and many other improvements. The P-2 being rendered obsolete by the P&W R-1340 Wasp. By 1930 Wright increased the bore to make the R-1820 "E" series engine and the Cyclone 9 went on through the "F", "G", "G-100", "G-200" and "H" series engines, last engine delivered Dec of 1963.

Aside from keeping the same bore and stroke *everything* else was changed. For example one difference between a G-100 engine and a G was the introduction of a forged steel crankcase instead of forged aluminium (which had changed from cast aluminium on "F" sereis) . It weighed 30lbs more but was 50% stronger. The G-100 was introduced just 20 months after the G. The G-200 changed crankcases again, still using steel but back to the weight of the aluminum crankcase but even stronger than the first steel one. It followed the G-100 by 26 months. There were changes in pistons, connecting rods, crankshafts, main bearings, cylinder heads ( from cast to forged) and cylinder barrels. The engine went from 920lb for an R-1750 E with reduction gears and running on 50 octane fuel to 1469lbs for a late "H" running on 115/145 fuel. Early versions used 12 hold down bolts per cylinder, changing to 16 bolts on the middle engines and finally 20 bolts per cylinder on the "H" engines.
The "H" was first delivered Oct 1942 although there was quite a bit of overlap (sometimes years) between the start of production of one series of engines and end of another series. 

There were also a host of modifications even in a particular series of engines. While the "Cyclone 9" may have been marketed or sold for over 36 years it is quite debatable as to if it was the _same_ engine.

Edit: To clarify the start of the Russian program/development in the fall of 1932 the Russians sent a delegation to the US to negotiate a "deal" for the Cyclone 9 engine with Wright. The "deal" included Wright providing documetaion in metric units and to build and test pattern engines built to the metric system. A Nov 1933 STO decree covered the purchase of about 150 complete engines, 100 engines as parts and and enough of the most complex components for another 100 engines. First Engine was shipped to Russia in Dec 1933. Metric engine completed a 100 hr test in the US in April 1934. By 1936 complete M-25 engines were being built in Russia with no imported parts. This was the _start_ of the series of engines that lead to the ASH-73 used in the TU-4 bomber.

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## Balljoint (Apr 22, 2014)

Once the decision was made to go with the B-29 there wasn’t much wiggle room. By June, 1942 bi9g commitments were already made as illustrated by;

http

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## fastmongrel (Apr 23, 2014)

Balljoint thanks for that link fascinating stuff.


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## wuzak (Apr 23, 2014)

Much emphasis on the delays to the B-29 program is about the engines, but how much did issues with other sub-systems slow the program? Or was it mainly getting the systems to work together?


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## fastmongrel (Apr 23, 2014)

The B32 had problems with its gun system, so much so that Consolidated removed the remotely controlled gunnery system and fitted normal manned turets. I wonder if Boeing had problems with the guns or was it just that Consolidated couldnt integrate the system.


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## FLYBOYJ (Apr 23, 2014)

I'm not sure if Boeing ever had any real issues with the fire control system in the B-29, but they did toy with manned turrets.

http://www.ww2aircraft.net/forum/aircraft-pictures/odd-b-29-a-39837.html#post1094885

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## Jugman (Apr 23, 2014)

The R-3350 was not nearly as bad of an engine as is often claimed. As flawed as the early R-3350 was, much of the trouble in service were caused by the very poor engine installation of the B-29. No radial would have worked well in the B-29 nacelle as designed.

The B-29 was never expected to be combat ready before January 1944. That was probably an unrealistic goal to begin with. Its first combat mission was Jun 5, 1944. That is less than 22 months after its first flight. It took the Halifax, Manchester, and Liberator bombers between 15-19 months. Most combat aircaft the had their first flight at the onset of or during the war were in this range. Generally the more sophisticated the aircraft the longer it tended to take. Production examples were leaving the factory less than a year after its first flight. That's about the same time it took the B-24, P-39, P-47, and P-51. 

Honestly what do people expect?

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## tomo pauk (Apr 23, 2014)

Hello, Jugman: care to shed some light about the pecuilliarities of the B-29 engine installation?


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## GrauGeist (Apr 23, 2014)

Another way to validate the R-3350 fire tendancy...

Let's see how many other applications were prone to fire.

Here's other aircraft that used the R-3350 at one point or another. From this list, the one type that did have trouble with onboard fires, was the Mars JRM and an observation regarding the Mars, was that it had a close-fitting cowl assembly. On the otherhand, there are many types on the list that did not have trouble.

Beechcraft XA-38 Grizzly
Boeing B-29 Superfortress
Boeing XC-97 Stratofreighter
Boeing XPBB Sea Ranger
Canadair CP-107 Argus
Consolidated B-32 Dominator
Curtiss XBTC-2
Curtiss XF14C
Curtiss XP-62
Douglas A-1 Skyraider
Douglas BTD Destroyer
Douglas DC-7
Douglas XB-19
Douglas XB-31
Fairchild C-119 Flying Boxcar
Fairchild AC-119
Lockheed Constellation
Lockheed L-049 Constellation
Lockheed C-69 Constellation
Lockheed L-649 Constellation
Lockheed L-749 Constellation
Lockheed L-1049 Super Constellation
Lockheed C-121 Constellation
Lockheed R7V-1 Constellation
Lockheed EC-121 Warning Star
Lockheed L-1649A Starliner
Lockheed P-2 Neptune
Lockheed XB-30
Martin JRM Mars
Martin XB-33 Super Marauder
Martin P5M Marlin
Stroukoff YC-134


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## Shortround6 (Apr 23, 2014)

The Problems were several, some with the engine and some with the cowling. In an effort to streamline the plane the cowling's front opening was a bit too small for ground running or low speed operation. BTW the Lockheed Constellation had some problems with engine cooling too. 







Please note the cooling flaps in open position and drag. While the initial design _might_ have been OK in certain climates the majority of the early B-29 use was either hot or high or both. Put that together with max loads and short runways and the plane was being operated very close to the margin if not over at times. 

The B-29 went through 4 different dash numbers (at least) of R-3350 engines before it even went past the "A" model and some of them were to address the cooling issues as were the fitting of cuffs of the prop blade roots to increase cooling air flow. I don't know if there were changes to the cowl also. There were different internal cowl baffles ( or baffles mounted on the engine) different oil systems to give more oil to the 3 top rear cylinders which showed the most tendency to overheat. Fuel injection was used for better fuel distribution ( 3 top rear cylinders ran leaner?) 

A major problem with re-powering the B-29 was not the take-off or war emergency power ratings of the engines but the max continuous rating ( often used for climb) which for the R-3350s used in the B-29s was _supposed_ to be 2000hp at 2400rpm as long as the engine temperature would allow. This is only 200hp below the take-off power and is a rather high percentage compared to most WW II aircraft engines for example while the R-2800 used in the P-47 was rated for 2000hp military and take-off it was only rated at 1625hp max continuous. Given the altitude and speed a B-29 would be at 5 minutes after _starting_ it's take-off run any replacement engine needs a very high max continuous power setting. (V-3420 may have offered 2100hp in early versions).

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## Shortround6 (Apr 23, 2014)

GrauGeist said:


> Another way to validate the R-3350 fire tendancy...
> 
> Let's see how many other applications were prone to fire.
> 
> ...




The thing is that there were a _series_ of R-3350 engines and most, if not all of the post war planes got the later versions, There were BA, BB, BC, BD, C and DA series engines at the very least. 

Another thing is operating conditions and aircraft weights. A B-29 went about 120,000lbs Normal and 135,00lbs max overload. A Lockheed 649 (with post war engines) was 94,000lbs max take-off weight. It didn't have to flog the engines quite as hard.

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## GrauGeist (Apr 23, 2014)

Sure and there were mechanical changes to the design of the engine during wartime production, one of which, was the increase of the number of cylinder cooling fins (amongst other things)

The R-3350 was an ongoing evolution, just like everything else.


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## Shortround6 (Apr 23, 2014)

That is very true and unfortunately the B-29 got to be the plane that went into action first with the R-3350 and bore the brunt of the debugging process. 
Imagine the howls and internet bandwidth if the Napier Sabre had gone into service on a 4 engine bomber?


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## GrauGeist (Apr 23, 2014)

Shortround6 said:


> Imagine the howls and internet bandwidth if the Napier Sabre had gone into service on a 4 engine bomber?


Yep!


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## tomo pauk (Apr 23, 2014)

Shortround6 said:


> ...
> Imagine the howls and internet bandwidth if the Napier Sabre had gone into service on a 4 engine bomber?



That would be a helluva bomber in 1943?


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## OldSkeptic (May 3, 2014)

gjs238 said:


> Knowing of the Wright R-3350 Duplex-Cyclone reliability issues extended development time, could we turn back the clock and get the B-29 deployed sooner using different engines or engine arrangements?



Why bother? Bombing accuracy from 20,000ft was woeful so why go to 30,000ft? To be less accurate?

The plane was insanely expensive to develop (comparable to the Manhatten project from memory). 
It failed at it's primary design task and then was switched to low level incendiary bombing over Japan, which could have been done by B-24s at a fraction of the cost. 

The plane was a failure by any objective measure.


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## FLYBOYJ (May 3, 2014)

OldSkeptic said:


> Why bother? Bombing accuracy from 20,000ft was woeful so why go to 30,000ft? To be less accurate?


Have you ever heard of bombing by radar? It was done quite effectively during WW2 and Korea at higher altitudes.


OldSkeptic said:


> The plane was insanely expensive to develop (comparable to the Manhatten project from memory).
> It failed at it's primary design task and then *was switched to low level incendiary bombing over Japan*, which could have been done by B-24s at a fraction of the cost.



That was the choice made by the operator and the environment it was being operated (Jet stream issues). The low level missions were accomplished to bring Japan to her knees QUICKLY, and based on what was being bombed and the construction of the buildings and factories, this was a perfect deployment of an aircraft that accomplished the mission successfully. No Lancaster, B-24 or He177 could come close to completing the firebombing of Tokyo from the bases the B-29 were being operated from. The B-24 would not have had the legs or bomb carrying capacity to accomplish what the B-29 did, PERIOD! 

Additionally the other contribution that the B-29 completed (and detractors of the B-29 either fail to recognize or ignore) was mining operations that probably would have strangled Japan as well as continued fire bombings and actual invasion. .

_Operation Starvation sank more ship tonnage in the last six months of the war than the efforts of all other sources combined. The Twentieth Air Force flew 1,529 sorties and laid 12,135 mines in twenty-six fields on forty-six separate missions. Mining demanded only 5.7% of the XXI Bomber Command's total sorties, and only fifteen B-29s were lost in the effort. In return, mines sank or damaged 670 ships totaling more than 1,250,000 tons.

*After the war, the commander of Japan's minesweeping operations noted that he thought this mining campaign could have directly led to the defeat of Japan on its own had it begun earlier*._

Operation Starvation - Wikipedia, the free encyclopedia



OldSkeptic said:


> The plane was a failure by any objective measure.



16 years and two wars of service for a "failure" that had one of the lowest combat loss rates of any heavy bomber ever produced. 

Your unsubstantiated opinion - regardless how the "operator" deployed it, the B-29 was the best heavy bomber of WW2 and one of the best heavy bombers ever developed. No other allied or axis aircraft could have accomplished what the B-29 did in the time it was operated, and I'll exclude the atomic bomb operations from MY opinions!


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## GrauGeist (May 3, 2014)

another point to consider...

Of the B-17, B-24 (or other heavy bombers interred or otherwise), the Soviets chose to copy the B-29. There is a reason for that.

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## RCAFson (May 3, 2014)

An interesting article on the the B-29:

The B-29?s Battle of Kansas

particularly the cost effectiveness comments.


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## FLYBOYJ (May 3, 2014)

RCAFson said:


> An interesting article on the the B-29:
> 
> The B-29?s Battle of Kansas
> 
> particularly the cost effectiveness comments.



"Initial operations from China indicated that the B-29 was a potential failure, but *under LeMay’s leadership, the B-29 came to symbolize airpower. It offered, at an ever-decreasing cost in aircraft and personnel, the option of victory over Japan.*"


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## RCAFson (May 3, 2014)

Japan was pretty thoroughly beaten by the time Lemay started his low level firebombing tactics. US possession of Okinawa and Iwo Jima meant that the B-29 was no longer the only option for a strategic bombing campaign against Japan.

To put things in perspective, the $3 billion B-29 program cost more than the combined cost of the all the USN's new battleships and aircraft carriers.


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## FLYBOYJ (May 3, 2014)

RCAFson said:


> Japan was pretty thoroughly beaten by the time Lemay started his low level firebombing tactics.


A 1,000,000 man army and over 5,000 aircraft available (Jablownski, Wings of fire, 1971) No one saw white flags being hoisted.


RCAFson said:


> US possession of Okinawa and Iwo Jima meant that the B-29 was no longer the only option for a strategic bombing campaign against Japan.


I could agree to a point but no one knew the full capacity of the Japanese war machine and how long they were willing to continue the war.


RCAFson said:


> To put things in perspective, the $3 billion B-29 program cost more than the combined cost of the all the USN's new battleships and aircraft carriers.


Money well spent for what it brought to the table as a combat aircraft, aviation development and post war missions, I could also go into the economic aspects of employing people during its production, post war deployment, modification as a tanker, and later as a weather recon aircraft.

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## GrauGeist (May 3, 2014)

RCAFson said:


> Japan was pretty thoroughly beaten by the time Lemay started his low level firebombing tactics. US possession of Okinawa and Iwo Jima meant that the B-29 was no longer the only option for a strategic bombing campaign against Japan.


Japan was not beaten until the Emperor said they were...
Every man, woman and child was ready to defend Japanese soil to the death, even if it meant meeting Allied soldiers with sharpened sticks.



RCAFson said:


> To put things in perspective, the $3 billion B-29 program cost more than the combined cost of the all the USN's new battleships and aircraft carriers.


B-24s cost $5,500,742,219 and the B-29 had a far higher range and far higher max. capacity per airframe. So technically, the B-24 was a waste of money, right?


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## OldSkeptic (May 3, 2014)

Yep it was. It was designed and originally used to drop bombs from 30,000ft in day time. They dutifully used it in that way. Now they couldn't accurately drop bombs from 20,000ft at that time so it was even less accurate than all the daylight B-17s, B-24s in the ETO. 

The impact on Japan was similar to Germany, limited (mining, the submarine blockade and the later naval blockade had a far greater effect). Plus by the time the B-29 bombing got really going they were bombing Japan from aircraft carriers....

So they turned it into a low level (less than 5,000ft) night time incendiary bomber and stripped out a lot of stuff out of it (guns, etc). Now anything could do that. All that money spent on giving it all that high altitude performance was wasted. And what it ended up doing could have been done by a lot of other, far cheaper aircraft.

As for the nukes. The Fat Boy weighed 10,300lbs, the Little boy 9,700lbs. A Lanc could carry that.... as for the range, my rough calculations make it that a Lanc with that load (and a late model with late model Merlins) needed a minimum of another 600 UK gals of fuel (4,500lbs) to make it from Tinian to Hiroshima and back. Say make it 700 UK gals and 5,200lbs for a reserve. Need a bit of tricking up and stripping out, but they did that with B-29 too. 

Anyway they could have done it from Okinawa by that time, which B-24s bombed Japan from, round trip about 1,300 miles ..easily within a Lanc's range. Heck at that range you might have been able to trick up a B-24 to carry the nukes (maybe, Fat Man maybe yes, Little Boy maybe not because of the shape).

The B-29 cost $640,000*. B-24 $300,000 and the Lanc (at a 4:1 exchange rate of the time) $200,000.
That must be just the manufacturing cost, adding the development costs I get $1.4 million per plane. But I don't have the equivalent B-24 and Lanc development costs, but you'd expect them to be a heck of a lot less....

So back to the original point, what could a B-29 militarily do that another aircraft of the time couldn't also do at a fraction of the cost (albeit with a bit of tricking up)?


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## FLYBOYJ (May 3, 2014)

OldSkeptic said:


> Yep it was. It was designed and originally used to drop bombs from 30,000ft in day time.* They *dutifully used it in that way. Now they couldn't accurately drop bombs from 20,000ft at that time so it was even less accurate than all the daylight B-17s, B-24s in the ETO.



"THEY" also discovered that there was this "THING" called the JET STREAM that made conventional high altitude bombing difficult over Japan. "THEY" did a great job identifying the problem and fixing it because "THEY" had a great aircraft to work with.


OldSkeptic said:


> The impact on Japan was similar to Germany, limited (mining, the submarine blockade and the later naval blockade had a far greater effect). Plus by the time the B-29 bombing got really going they were bombing Japan from aircraft carriers....
> 
> So they turned it into a low level (less than 5,000ft) night time incendiary bomber and stripped out a lot of stuff out of it (guns, etc). Now anything could do that. All that money spent on giving it all that high altitude performance was wasted. And what it ended up doing could have been done by a lot of other, far cheaper aircraft.


 Could have, would have, should have, and when the mission was done all the equipment went back in and the B-29 became the backbone of the Strategic Air Command AND RAF Bomber Command in the post war years, with that said, your point?


OldSkeptic said:


> As for the nukes. The Fat Boy weighed 10,300lbs, the Little boy 9,700lbs. A Lanc could carry that.... as for the range, my rough calculations make it that a Lanc with that load (and a late model with late model Merlins) needed a minimum of another 600 UK gals of fuel (4,500lbs) to make it from Tinian to Hiroshima and back. Say make it 700 UK gals and 5,200lbs for a reserve. Need a bit of tricking up and stripping out, but they did that with B-29 too.


 Again, "could have, would have, should have." Do you even come close to realizing how much 6 or 700 UK gallons is when shoving it into an aircraft even one the size of a Lancaster or B-29???? A non-pressurized single pilot tail dragger bomber that couldn't get over 20,000 feet carrying a nuke was and is an accident waiting to happen. Yea, "tricking and stripping out," Just like Lemay did, right? 


OldSkeptic said:


> Anyway they could have done it from Okinawa by that time, which B-24s bombed Japan from, round trip about 1,300 miles ..easily within a Lanc's range. Heck at that range you might have been able to trick up a B-24 to carry the nukes (maybe, Fat Man maybe yes, Little Boy maybe not because of the shape).


See above - the Lanc "Could Have" done a better job than the B-24 in the PTO if used in the same capacity as the Liberator was with the 5th AF, IMO the Lanc was better than the B-24, but the Lanc was no intercontinental bomber in the same class as the B-29 and I'll once again revert to the fact of the 90 B-29s operated by Bomber Command into the 1950s. Why was that?????


OldSkeptic said:


> The B-29 cost $640,000*. B-24 $300,000 and the Lanc (at a 4:1 exchange rate of the time) $200,000.
> That must be just the manufacturing cost, adding the development costs I get $1.4 million per plane. But I don't have the equivalent B-24 and Lanc development costs, but you'd expect them to be a heck of a lot less....


And both the B-24 and Lanc quickly saw the scrapyard in the post war years (I recognize that the Lanc was used in limited numbers but the majority of them were gone by the 1950s). The USAF got 16 years out of the B-29, two wars as well as the first aerial tanker fleet, so tell me, do you really want to continue to crunch numbers to show the real value of the B-29???


OldSkeptic said:


> So back to the original point, what could a B-29 militarily do that another aircraft of the time couldn't also do at a fraction of the cost (albeit with a bit of tricking up)?


Two Wars, Two Air Forces, a 10% combat loss rate for BOTH WW2 and Korea, the first nuclear deterrent, the first aerial tanker, 4 years with the RAF and 16 years of service. There's more, (like the Soviets copying it) shall I address those facts too???? With that said - "what could a B-29 militarily do that another aircraft of the time couldn't also do at a fraction of the cost?" The TU-4!!! Things are cheaper when you steal them and build them with slave labor!!!!

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## GrauGeist (May 3, 2014)

OldSkeptic said:


> Yep it was. It was designed and originally used to drop bombs from 30,000ft in day time. They dutifully used it in that way. Now they couldn't accurately drop bombs from 20,000ft at that time so it was even less accurate than all the daylight B-17s, B-24s in the ETO.


And yet, due to *atmospheric conditions* over the Japanese Isles, any bomber was met with the same frustration with warload delivery at designed altitudes. Be it a B-17, B-24, Lancaster or any other heavy bomber.



OldSkeptic said:


> The impact on Japan was similar to Germany, limited (mining, the submarine blockade and the later naval blockade had a far greater effect). Plus by the time the B-29 bombing got really going they were bombing Japan from aircraft carriers....


Keep in mind that the B-29 was also hammering targets in the CBI, from Asian bases, even though attacks against Japan were not as productive as hoped. So don't think that the B-29 was solely intended as a weapon against Japan.
Also, might want to double-check your timeline, the forward bases in the Pacific were secured in mid-1944, allowing for extreme long range bombing missions against the Japanese Islands as well as missions against Japanese held islands in the region. It wasn't until early in 1945 (February) that carrier based attacks were conducted against Japanese proper.



OldSkeptic said:


> So they turned it into a low level (less than 5,000ft) night time incendiary bomber and stripped out a lot of stuff out of it (guns, etc). Now anything could do that. All that money spent on giving it all that high altitude performance was wasted. And what it ended up doing could have been done by a lot of other, far cheaper aircraft.


I need to disagree here. One B-29 was capable of carrying a standard bomb load of 20,000 pounds long distance. For a bomber like the B-17 or the B-24, distance decreases as bombload increases. Even at max load for either one of those types, one B-29 is still doing the job of two bombers.



OldSkeptic said:


> As for the nukes. The Fat Boy weighed 10,300lbs, the Little boy 9,700lbs. A Lanc could carry that.... as for the range, my rough calculations make it that a Lanc with that load (and a late model with late model Merlins) needed a minimum of another 600 UK gals of fuel (4,500lbs) to make it from Tinian to Hiroshima and back. Say make it 700 UK gals and 5,200lbs for a reserve. Need a bit of tricking up and stripping out, but they did that with B-29 too.
> Anyway they could have done it from Okinawa by that time, which B-24s bombed Japan from, round trip about 1,300 miles ..easily within a Lanc's range. Heck at that range you might have been able to trick up a B-24 to carry the nukes (maybe, Fat Man maybe yes, Little Boy maybe not because of the shape).


Now we're entering the shady area of "what-ifs".
You're not only carrying a max load aboard, but now you want to load it down even more with extra fuel?
Obviously, the heavier it gets, the shorter the range...throwing more fuel onboard isn't going to somehow fix that.
One other thing to keep in mind, the altitude for Atomic bomb deployment was 30,000 feet and if memory serves me right (I may be off, here) the Lancaster's ceiling with a full bombload was 25,000 feet?



OldSkeptic said:


> The B-29 cost $640,000*. B-24 $300,000 and the Lanc (at a 4:1 exchange rate of the time) $200,000.
> That must be just the manufacturing cost, adding the development costs I get $1.4 million per plane. But I don't have the equivalent B-24 and Lanc development costs, but you'd expect them to be a heck of a lot less....


Again, the B-29 was an advanced piece of hardware...Aerodynamic advancements, new innovations in defensive turrets, pressurized cabin/personnel compartments, extreme load carrying, extreme long distance.
It carried a crew of 11 men and standard designed bombload of 20,000 pounds.
For a B-24 to match that bombload by comparable range, it would require four B-24 bombers.
That's four times aircraft cost each $298,000 = $1,192,000
That's four times the crewmen at 11 men each = 44 crewmen
Then let's factor in fuel for the four B-24s and logistics, support, maintenance, forward airbase area consumed and so on and so on.



OldSkeptic said:


> So back to the original point, what could a B-29 militarily do that another aircraft of the time couldn't also do at a fraction of the cost (albeit with a bit of tricking up)?


The economics have already been covered above and when the B-29 entered service, it reclassified "heavy bomber" and introduced the era of long-range strategic bomber.

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## GrauGeist (May 3, 2014)

lol Joe, ya' beat me to it!

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## Elmas (May 4, 2014)

Let’s see the B29 as a piece of engineering: B-29 was a post-WWII plane, all others planes of any other nation involved (Me 262 excepted, by my personal point of view) were pre-WWII airplanes.

The knowledge that American Air Industry acquired designing and building B29 was invaluable: capacity to succesfully handle very large programs, experience of sophisticated systems onboard and on the ground, pressurization (fundamental for civil aviation post WWII) etc. and so the American Air Industry was able, after the war, to make the best of it.

And this even if the B-29 had never dropped a single bomb in anger.


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## nuuumannn (May 4, 2014)

> what could a B-29 militarily do that another aircraft of the time couldn't also do at a fraction of the cost (albeit with a bit of tricking up)?



Be one of the most influential bombers in history. Need I add to what Joe and Dave have written already.

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## Reegor (May 5, 2014)

OldSkeptic said:


> Why bother? Bombing accuracy from 20,000ft was woeful so why go to 30,000ft? To be less accurate?
> 
> The plane was insanely expensive to develop (comparable to the Manhatten project from memory).
> It failed at it's primary design task and then was switched to low level incendiary bombing over Japan, which could have been done by B-24s at a fraction of the cost.
> ...


War = waste. After the fact, many programs did not live up to their early hopes. (Like others here, I don't agree that the B-29 was one of those. Someone mentioned the very effective inter-island mining program; B-29s were used to drop mines in areas that other vehicles could not reach safely/quickly, so they even get some of the credit for that. 

On the other hand, it's clear that the USAAF brass pushed the B-29 program as hard as they did (and before it, the bombing of Europe) because they were maneuvering to get an independent Air Force after the war. If the B-29 and the 8th Air Force had been seen as ineffective, it might have been fatal to that plan. Internal correspondence, and post-war autobiographies, were pretty frank about that motivation.


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## gjs238 (May 6, 2014)

In the context of defeating Japan, and not postwar USAF aspirations, weather ops, aerial tankers, etc., it seems the "B-29 way" of going about it was not terribly efficient. I believe Churchill had reservations about the program.

Of course, when the B-29 mission and aircraft were designed, folks were unaware of all that would eventually transpire.
With hindsight, knowing what transpired, perhaps there was a better "way" of going about the air offensive against Japan.
For example, knowing today that low level incendiary and mining operations were ideal, perhaps we would have built a different aircraft.
For the mission actually performed, is all the sophistication of the B-29 necessary?
Could another craft have been developed more quickly and cheaply?
Or as the thread began, perhaps just different engines (which seemed to comprise the bulk of the mechanical problems.)


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## Shortround6 (May 6, 2014)

For a true "cost" you have to look at the cost of delivering XXXX tons of bombs to the target area/s. B-29 or B-17 or B-24, nothing was going to drop with great accuracy from 30,000ft (or just under) over Japan due to the Jet stream.

A B-29 could carry 5,000lb at hi altitude over a 1600 mile *radius*, or 12,000lbs at low altitude over the same 1600 mile *radius.*
A B-24 could carry 5,000lbs over a 1700 mile *range*. So they didn't really do the same job. Depending on which bases you use when the B-24 either can't get there at all or is going to carry a _lot_ less bombs than the B-29. 

Using _TWO_ B-24s to deliver the same amount of bombs as a single B-29 may not be a cheap as it appears, The B-24s may use less fuel but you need two trained crews and more ground support personnel. The number of man hours of maintenance may be more for two aircraft. (144 spark plugs to change on a B-29, 224 spark plugs on two B-24s) and you are trying to maintain the aircraft thousands of miles from the factories. EVERYTHING needs to be transported across oceans, the bombs, the fuel the food for the men, on some islands even the drinking water ( or use desalinization plants).

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## RpR (May 6, 2014)

gjs238 said:


> In the context of defeating Japan, and not postwar USAF aspirations, weather ops, aerial tankers, etc., it seems the "B-29 way" of going about it was not terribly efficient. I believe Churchill had reservations about the program.
> 
> Of course, when the B-29 mission and aircraft were designed, folks were unaware of all that would eventually transpire.
> With hindsight, knowing what transpired, perhaps there was a better "way" of going about the air offensive against Japan.
> ...


Are you saying they should have gone with an improved B-19 which they easily could have?


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## Shortround6 (May 6, 2014)

The B-19 was obsolete on the day it flew. Douglas didn't even want to complete it ( they lost over a million dollars on the program). It took over 5 years to go from mock-up (not even start of design) to first flight and was thoroughly outdated in both aerodynamics and structure. It did make a good PR (press relations) aircraft though


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## nuuumannn (May 6, 2014)

> perhaps we would have built a different aircraft.



Perhaps, but you are forgetting that the B-29 would have been built at any rate. Like I said in a different thread, it was a natural progression from previous piston engined bombers to the next generation. It's technology was a considerable leap over previous types; that alone is why the B-29 was going to be built regardless of what was known at the time or what wasn't. If we don't progress technologically, we cannot expect to out do our enemies. It's evolution.


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## gjs238 (May 6, 2014)

nuuumannn said:


> Perhaps, but you are forgetting that the B-29 would have been built at any rate. Like I said in a different thread, it was a natural progression from previous piston engined bombers to the next generation. It's technology was a considerable leap over previous types; that alone is why the B-29 was going to be built regardless of what was known at the time or what wasn't. If we don't progress technologically, we cannot expect to out do our enemies. It's evolution.



Perhaps.
Perhaps it would have developed differently.
Perhaps another aircraft would have evolved.


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## GrauGeist (May 6, 2014)

The B-29 was also first put on paper before WWII broke out (though the war clouds were certainly on the horizon) and it was intended to be the next step in bombers.

When the battle of Britain was underway, the urgency of the B-29 project was very clear, because if England fell (which was a serious concern), this would have been the only option to effectively strike Europe.

While many don't seem to appreciate the B-29's capabilities, it cannot be denied that this long-distance record-setting bomber was a technical leap forward.

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## nuuumannn (May 6, 2014)

> Perhaps it would have developed differently. Perhaps another aircraft would have evolved.



I think you might be stargazing. Dave nailed it with this.

"While many don't seem to appreciate the B-29's capabilities, it cannot be denied that this long-distance record-setting bomber was a technical leap forward."

Its influence (again, I'm quoting from another thread) was enormous. Every big Boeing and Tupolev aircraft subsequent to the B-29 owed a (significantly large in terms of Tupolev) part of their existence to it. It was truly ground breaking.


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## RCAFson (May 6, 2014)

GrauGeist said:


> The B-29 was also first put on paper before WWII broke out (though the war clouds were certainly on the horizon) and it was intended to be the next step in bombers.
> 
> When the battle of Britain was underway, the urgency of the B-29 project was very clear, because if England fell (which was a serious concern), this would have been the only option to effectively strike Europe.
> 
> While many don't seem to appreciate the B-29's capabilities, it cannot be denied that this long-distance record-setting bomber was a technical leap forward.



The B-29 was very advanced and had comparatively great range but it certainly didn't have the ability to strike Europe from North America.


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## GrauGeist (May 6, 2014)

On 18 September 1945, three B-29s left Hokkaido for Washington D.C. After experiencing headwinds, they cut the trip short by landing at Chicago, refueled and then continued to D.C. While this distance was not record setting (the RAF held the distance record set in the late 30's), it was record setting in the fact that it set record for the longest U.S. military flight, the first flight from Japan to the U.S.(5,840 miles - 9,400km) and a record breaking gross weight of 144,000 pounds (65,300kg).

Two months later, on 19 November 1945, a B-29 flew from Guam to Washington D.C., breaking the long distance world record and a weight record, flying non-stop for 7,916 miles (12,740km). The B-29's gross weight was 155,000 pounds (70,000 kg) and the flight took just over 35 hours.


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## RCAFson (May 6, 2014)

GrauGeist said:


> On 18 September 1945, three B-29s left Hokkaido for Washington D.C. After experiencing headwinds, they cut the trip short by landing at Chicago, refueled and then continued to D.C. While this distance was not record setting (the RAF held the distance record set in the late 30's), it was record setting in the fact that it set record for the longest U.S. military flight, the first flight from Japan to the U.S.(5,840 miles - 9,400km) and a record breaking gross weight of 144,000 pounds (65,300kg).
> 
> Two months later, on 19 November 1945, a B-29 flew from Guam to Washington D.C., breaking the long distance world record and a weight record, flying non-stop for 7,916 miles (12,740km). The B-29's gross weight was 155,000 pounds (70,000 kg) and the flight took just over 35 hours.



Just because they managed to cram enough fuel into an aircraft to set a distance record doesn't make it able to carry a useful weapon load over those distances:



Shortround6 said:


> A B-29 could carry 5,000lb at hi altitude over a 1600 mile *radius*, or 12,000lbs at low altitude over the same 1600 mile *radius.*
> 
> .


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## FLYBOYJ (May 6, 2014)

gjs238 said:


> Perhaps.
> Perhaps it would have developed differently.
> Perhaps another aircraft would have evolved.



Based on the technology and accepted military doctrine of the day, I don't think anyone "would have" seen anything much different unless someone showed up in Arnold's office from the future with a crystal ball.


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## GrauGeist (May 6, 2014)

RCAFson said:


> Just because they managed to cram enough fuel into an aircraft to set a distance record doesn't make it able to carry a useful weapon load over those distances:


But the data recorded on those flights (and every other record setting flight made, for that matter) is useful in finding limits. These flights were also instrumental in analyzing the Jetstream and also led to trans-Pacific passenger service.

Anytime you push the envelope, you reset the bar.

Otherwise, the skies over Europe in WWII would have been contested by Spads, Sopwiths, Fokkers and the Albatros...


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## FLYBOYJ (May 6, 2014)

RCAFson said:


> Just because they managed to cram enough fuel into an aircraft to set a distance record doesn't make it able to carry a useful weapon load over those distances:


 Quite correct, but the potential was shown and in the post war years the useful weapon load focus was one bomb.

Eventually we saw other flights like this...

Lucky Lady II - Wikipedia, the free encyclopedia


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## RpR (May 6, 2014)

gjs238 said:


> Perhaps.
> Perhaps it would have developed differently.
> Perhaps another aircraft would have evolved.


You are correct; probably the B-32 would have been fully developed, the orders for the Martin B-33 would have been fulfilled, the ....


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## GrauGeist (May 6, 2014)

BobR said:


> You are correct; probably the B-32 would have been fully developed, the orders for the Martin B-33 would have been fulfilled, the ....


But the B-32 was a fallback design requested by the USAAC in the event the B-29 didn't pan out. Also look at the plague of problems the B-32 had through it's development, dragging the program timeline out.

It was so problematic, that as soon as WWII ended, so did the B-32. 

It's stellar career lasted a whole year.


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## RpR (May 6, 2014)

GrauGeist said:


> But the B-32 was a fallback design requested by the USAAC in the event the B-29 didn't pan out. Also look at the plague of problems the B-32 had through it's development, dragging the program timeline out.
> 
> It was so problematic, that as soon as WWII ended, so did the B-32.
> 
> It's stellar career lasted a whole year.


I do not disagree but if, as the poster implied, the time and money had NOT gone to the B-29 then probably either of the two I mentioned and or others would have received that money and flown.


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## FLYBOYJ (May 6, 2014)

BobR said:


> I do not disagree but if, as the poster implied, the time and money had NOT gone to the B-29 then probably either of the two I mentioned and or others would have received that money and flown.



Or this one...

Lockheed B-30A Galaxy


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## GrauGeist (May 6, 2014)

You can throw money by the handful at something and that doesn't magically make it happen. The list is a long one, of projects that consumed money and time, but never proved to be the right avenue.

The Germans did it, the Americans did it and yet, it was the B-29 that emerged successful not only in wartime, but postwar as well. A good example was the B-32. It simply was a PoS that no matter how much money you dump on the project, it was a PoS.

The B-17 went on for many years after the war, serving in many capacities, the B-24 did to a certain degree, also. The B-29 went on for many years and the B-32 was killed off before the dust even cleared from the last battlefield. There is a reason for that.


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## FLYBOYJ (May 6, 2014)

I think the B-32's success would have been "iffy" to say the least had it been deployed, that also depending if the war would have lasted longer. From Joe Baugher's site, note the few "good things" about the aircraft...

_"In service, the B-32 had numerous deficiencies. The cockpit had an extremely high noise level and the instrument layout was poor. Bombardier vision was rather poor. The aircraft was overweight for the available engine power, the mechanical subsystems were inadequate, and there were frequent engine fires caused by a faulty nacelle design. There were frequent undercarriage failures, which caused the type to be grounded briefly during May of 1945. *On the plus side, the B-32 had excellent low-speed directional control, good takeoff and landing characteristics and rapid control response. The B-32 was a stable bombing platform, its manned turrets provided good protection, its subsystems were easily accessible for maintenance, and its reversible inboard propellers gave it excellent ground-handling characteristics.* 

Many of the problems encountered during the B-32 service tests were eliminated in subsequent production aircraft, either through design changes or through better quality control during manufacture. 

An August 1944 directive from the USAAF had required that a combat test be carried out before the B-32 could be introduced into service. However, the AAFPGC agency opposed both a combat test and general service introduction of the B-32, so it seemed that the Dominator would be consigned to operational limbo indefinitely. In the meantime, Lt. Gen. George C. Kenney, the commander of the Far East Air Forces, had been anxious to get B-29s but his requests had always been turned down on the grounds that the B-29s were urgently needed elsewhere. As an alternative, General Kenney started requesting B-32s instead. On March 27, General Arnold approved Kenney's request and authorized a comprehensive Dominator combat test. 

Col. Frank R. Cook was appointed commander of the test detachment. Three B-32s were chosen for the combat test (42-108529, -108531 and -108532). -108531 was damaged in an accident before leaving Fort Worth, and was replaced by 42-108528. -108528 was in rather bad shape, since it had been used as a test machine at Fort Worth. The first two arrived on Luzon on May 24, with the recalcitrant -108528 not arriving until the next day. The test was to be carried out under the auspices of the 5th Bomber Command, with the 386th Bombardment Squadron of the 312th Bombardment Group as the host unit. The 312th BG had four squadrons (386th, 387th, 388th, and 389th) that had been operating A-20s, and if things worked out well, all of the A-20s flying with the 386th and 387th BS would be replaced by B-32s. However, by the end of the war only the 386th and 387th had made the transition to the B-32, with the 388th and the 389th Squadrons still retaining their A-20s. 

The first combat mission took place on May 29, 1945. It was a strike against a Japanese supply depot in Luzon's Cayagan Valley. All three of the Dominators were to take part, but -108528 aborted on takeoff. The other two proceeded to the target. There was no opposition, and bombing runs were made from an altitude of 10,000 feet, and both aircraft returned without incident. This raid was followed by a series of attacks on Japanese targets in the Philippines, in Formosa, and on Hainan Island in the Tonkin Gulf. The only opposition encountered during these missions was some rather inaccurate flak. The tests were thus deemed a success, and plans were made to convert the entire 386th Bombardment Squadron to B-32s. The 312th BG was scheduled to move to Okinawa as soon as the conversion of the 386th BS to the B-32 was completed. 

Following the dropping of the atomic bombs, in August of 1945, the unit was ordered to move to Okinawa before the conversion could be carried out. Six more B-32s joined the squadron on Okinawa a few days later. Combat operations continued in spite of the de-facto cease-fire that had been called following the bombing of Nagasaki. During this time, the B-32s flew mainly photographic reconnaissance missions, most of which were unopposed. However, on August 17 a group of 4 B-32s flying over Tokyo were fired on by radar-directed flak and were attacked by Japanese fighters. The American aircraft escaped with only minor damage, claiming one confirmed fighter kill and two probables. During a reconnaissance mission over Tokyo on August 18, 42-108532 and 42-108578 were attacked by Japanese fighters. The American gunners claimed two kills and one probable, but -108578 was badly shot up and one of her crew was killed with two being injured. This was to prove to be the last combat action of World War 2. 

The last Dominator mission of the war was flown by four B-32s on August 28 in a reconnaissance mission to Tokyo. The mission was a disaster, although not because of any enemy action. 42-108544 lost an engine on takeoff and skidded off the runway. All 13 men aboard perished when the aircraft exploded and burned. On the way back from the target, 42-108528 lost power on two of its four engines. The plane's pilot ordered the crew to bail out, but two men were killed. 

After VJ-Day, the surviving B-32 aircraft were ordered to return to the USA. All further production of the B-32 was cancelled in September/October of 1945. At the time of cancellation, Fort Worth had produced 74 B-32s and 40 TB-32s, and San Diego had built only one. The last six fully-equipped Dominators (42-108579/108584) were flown from the production line directly into storage at Davis-Monthan and Kingman, Arizona. Twelve additional aircraft in shop-assembled status at San Diego and Fort Worth were declared "terminal inventory" and were also flown directly to disposal sites. At least 37 partially-assembled machines were stripped of all their government-furnished equipment and engines and were scrapped on site by the contractor. Those Dominators that were already in service were flown to the nearest disposal center, and all the non-flyable examples were scrapped in place. By 1947, most of B-32s that had been sent to the disposal centers had been scrapped." _


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