Maneuverability vs Speed

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Hi Shortround,

Not arguing with you at all here, but I have seen maybe 200 Allison crankshafts. They were all one of two varieties.

One has 6 counterweights on it and the other has 12 counterweights on it. Now, they made a lot of Allisons and 200 is not a large sample when looking at the total, but the actual crankshafts look pretty identical with the exception of counterweights, finish-wise, especially after using a crank polisher.

I don't know if the V-1710 Allison boat engine had a different crankshaft or not. I've seen one boat engine, but we didn't disassemble it because we only did that when we went to overhaul it and nobody was ordering a boat Allison from Joe Yancey while I was around there. I'd love to put one in a boat, for sure! There is also some mention of an unsupercharged version of the V-1710 that I have not seen and do not know if the crankshaft might be different, either. I think not for both because the crankshaft fits within the power section and bolts to whatever it turns in front or out back. The crankshaft itself has some 55 - 60 individual parts that take an assembly setup. Once assembled it doesn't need periodic tightening.

None of the above means they didn't have the cranks and crank issues you mentioned above. I just haven't seen them in my time with Allisons out of the approximately 150 Allisons I have seen up close and personal.. Still, Joe's collection of Allisons was not "cherry picked." He bought where he found them in fields, barns, etc. You'd THINK some other type of crankshaft would show up in a random sample of 150 Allisons if very many were made. But, hey, maybe not.

Joe had a 6-counterweight crankshaft spin up to 4,500 rpm in a tractor engine in Europe without damage. They shipped it back to him and he couldn't find anything wrong with it, even after magnaflux. It's back in the tractor and running as you read this.
 
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Just going by
"Vees for Victory" there is a chart on page 409 that shows a chart with the stress levels going up the left side and scale going across the bottom with cycles to failure in millions.

3 lines on the graph for 'Plain". "Shot Peened" and "Nitrided"

These would all have been 6 counterweight crankshafts.

The 12 counterweight cranks didn't show up until later (well into 1943 or 1944?) The last 560 P-40Ns got V-1710-115 engines with the 12 counterweight cranks as did a lot of other 1944/45 Allison's.

I think we have discussed this before. Judging by the number of engines built the plain crank shafts would have been in the low single digits as far as production goes, In fact the combination of both plain and shot peened may have been under 20%.
10,850 engines built through March of 1942.
52,250 engines built April of 1942 to Dec 1944.
Unknown after that.
Don't even want to guess as to how many of the early engines went overseas and how many stayed behind or what crankshafts were used in wartime over hauls.

Anybody building an Allison after WW II would be boarding on criminal negligence not to use the nitrided or 12 counter weight cranks.

according the chart the nitteded crankshaft will past 10 million cycles at a stress level that will cause a failure in the shot peened crank at 0.1 million cycles.
And the Plain crank could fail at 0.12 million cycles at stress level that the Shot peened crank will last 10 million cycles.
 
I've seen the same things about the Allisons nitrided peened etc., crank case and shaft, and also something about indium coated bearings in the later -73 and later variants. In many different sources. I imagine most of the post-war ones would be the late wars types like the -115.
 
Well, at least for an airplane.

For boats or tractors or cars, nothing wrong with a 6-counterweigfht crankshaft. Most of the tractors running Allisons in Europe are running them.
 
After some thought, and some reading, it seems that most of the differences between Japanese and European/American wartime aviation lay in the nature of China and of the Pacific Theater, the great distances primarily, and not necessarily in a zealous focus on maneuverability or lacking technology or designs. If this were the case, one of the primary reasons for making this thread is now moot, though I feel it's not entirely worthless. Ultimately, it seems that level flight speed is merely one aspect of maneuverability, and turning and role rates and speed are both similarly important, and are useful for different aspects of aerial combat. In addition, the human element cannot be discounted, a point that has been touched upon numerous times throughout the discussion.

I'm still not entirely convinced that Japanese aviation was on par with the world's best; yes, a war was ongoing, one that ended up going terribly for the country, but the Japanese were reportedly planning the production of fleets of Ki-84s underground, all of which would most likely have varying degrees of unreliability, towards the war's end, compared to the Germans, who were also in a similarly poor situation, but were constructing fleets of jets underground, all more advanced than any aircraft Japan could hope to build, even if they would have been similarly unreliable.


The Japanese had been toying with indigenous ramjet designs in the past, but those were never realised.

Mere fantasy. Even Italy had a jet aircraft prototype that actually took to the air.

Look, I don't like Nazi Germany, and from what I've heard in the past, a sizable amount of their achievements had their roots in the Weimer Republic and earlier, but their fighting ability and record was, at the very least, somewhat impressive, and that's not to speak of the dominance of the German language, for many years, in science and technology. As I hope I communicated across earlier, this topic involved the comparison of aircraft design philosophies, which is why I brought up one of the paramount powers of the period, and a 'fellow' Axis ally to boot.

I'm uncertain about the real speeds of Japanese wartime aircraft, seeing as a fairly wide range of speeds have been cited for them. I guess seeing a Zero actually achieve 333mph, or an N1K2-J ~410mph, in level flight in multiple directions, would help immensely. Obviously, this would most likely require near-perfect replicas of said aircraft, built according to the best methods and equipment Japan had access to then. Nothing less, though maybe some accurate simulation, using industrial grade software (not Il-2 or some other 'flight simulator'), and based on references of the equipment in real life, could potentially suffice. Paper calculations would simply fall short. It sounds absurd, but this is what it would take to convince me. I don't expect any of this to happen anytime soon.

Ultimately, I don't have much more to say, and I will largely refrain from posting, except for replies, and I will likely stop responding at some point in the near future, as I did during the intervening period between my last post and this current one. I will admit one point, and its that the Ki-84 doesn't look all that bad, though its appearance is still rather plain for me.

Edit: it would seem that this quote I found is unreliable, based on previous discussion here, but how true is it?

"The preference of Japanese fighter pilots for the Ki-27's high rate of turn caused the Army to focus excessively on manoeuvrability, a decision which later handicapped the development of faster and more heavily armed fighters."

Edit #2: There's also the unaddressed issue of relatively fast designs like the Ki-11, Ki-12 and Ki-28 being rejected for reasons related to weight, complexity and apparently lacking maneuverability. Wieliczko & Prusza in their 2004 book on the Ki-27, make the claim that there existed "maneuverability" and "speed" factions in the interwar IJA, and that the former won the debate on the issue, although their designs were not much slower at the time. How true is all this? This particular matter is the reason why I created this thread in the first place.

Edit #3: On a bit of a tangent, if the speeds for aircraft such as the P-47 were with WEP, is there any information on what their speeds would have been at military power? Would they have actually been roughly similar to late-war Japanese aircraft at lower altitudes? If it was somehow the case, could there have been, let's say, a >630kph P-47D at 5000-6000m? Would feel surreal.
 
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GregP said:
but they DID tend to foul spark plugs faster than Allisons
Click to expand...
I read where a P-51 pilot went down over France in early 1944 and was captured because they used the wrong spark plugs in the early P-51B. I found that shocking but I guess they naturally would use the same kind as the other US fighters used until they found out otherwise..
 
I think while it is true that the Germans made some great kit in WW2, I think perhaps their greater accomplishment was propaganda about how great they were. It still resonates with a lot of people. The British and the Americans both also had jets, they didn't put as much priority into the production and development because they were not going for a 'hail Mary pass' the way the Germans were with their uber-weapons programme, and when it came to special projects, their emphasis was on other things with a bigger payoff. But I don't think they were lagging behind the Germans across the board.

We tend to focus a lot on the successful German projects and designs. The Me 262, the Arado 234, the He 162 were all quite impressive aircraft. Certainly on the design level. But they were not available in sufficient numbers to stop much less sophisticated systems like Lancaster bombers and B-17s.

When it comes to 'uber weapons' - the US developed the atomic bomb and the B-29, and neither the Germans, nor the Japanese, had any answer for that. Of course, by the time it was ready, the German war machine was already crushed, mainly by the Soviets. The T-34, PPsh-41, Katyusha rocket, the Su 100 and the Il-2 may not seem as glamorous as a Panther or an MG 42, but they are what mainly annihilated the German army.

The British, with some significant contributions by Poles and others, cracked the German code which was a major problem. A technological triumph for the English and an ever worsening catastrophe for the Germans. The British put a lot of effort into Ultra and related projects. They also developed radar, more quickly and better than the Germans. The Spitfire which was a match for the best German fighters up to the jets. The Mosquito which ran rings around German night fighters and led raids no other aircraft could fly, and the Gloster Meteor was flying by 1943. The US put massive resources in the Manhattan project, the Norden bomb-sight, and the mass production of their most successful designs - B-17, B-24, P-51, P-47, P-38, F4U, F6F etc. They also developed the P-80, the B-29, and they had the FJ-1 flying in 1946 and the F-86 flying by 1947. Both of which could have arrived earlier if an urgent need for them was perceived, but the German jets never became that level of threat.

The Japanese "Uber weapons" mainly came early - the A6M was certainly a world-class, fear inducing shock when it appeared. The type 93 torpedo (aka known in Anglophone circles as "Long Lance") turned out to be a devastatingly effective naval weapon, making even fairly average bombers into deadly ship killers. These two weapons alone contributed to the astonishing success the Japanese had in the early war in taking immense territorial prizes from the Western powers. The Japanese aircraft carriers were new and sophisticated technology, something that the Germans certainly never matched, and were definitely in the running for the best in the world. And let's not forget that they also created the worlds largest and most formidable battleships in the Yamato and Musashi. The fact that they didn't really impact the war that much can also be said for the German jets and rockets, or their giant battleships (which seem to get a lot better press). The Japanese also developed technology like submarine aircraft carriers.

I would say when it came to the most sophisticated weapons, including aircraft, the Japanese focused on naval designs. The B7A was probably the best dive bomber design of the war, an order of magnitude more sophisticated and effective than a Stuka. If the Germans had developed a plane like that in say, 1943, it might have been extremely helpful to their war-efforts. (The Soviet Pe-2 and later Tu-2 were also arguably better than the German Ju 88 as dive bombers, while the best attack bomber of the war after the Mosquito was arguably the US A-26).

The Italians and French also had some very good aircraft designs during the war, their only limitation was that they never developed very powerful engines like the British, Germans, and Americans did. The Fiat G55 and Re 2005 were probably more promising fighter designs than any propeller based German fighter (the Germans themselves thought so, and considered producing them, but decided they took too many man-hours to build). The very early French D.520 fighter remained competitive into the mid-war despite not seeing any improvements from it's 1940 standard. French engines like the 12Y, though disregarded around here, were widely adapted by multiple nations and it or it's derivations powered many highly successful aircraft, including the D.520, the Pe-2 and the Yak-3. The Swiss and Swedes created weapons like cannons and AA guns in wide use by numerous countries, including the Germans who relied heavily on them. The Czechs also created many highly sophisticated designs which the Germans adapted for their own purposes (Pz 35 and 38 tank for example) as did the British (the excellent bren and besa machine guns). Dutch firms made sophisticated aircraft like the D.XX1 and the G.1, and the Romanians also produced the superb IAR 80, in part derived from earlier Polish designs. Skill at design was not necessarily concentrated in one place.

When we do look at the German kit, we tend to focus a lot on their best successes. We look at the excellent Bf 109, which stayed competitive, albeit with major flaws, through the end of the war. Competitive but certainly not dominant after say, 1942, as the British and Americans kept up, and by later 1943, the Soviets as well. The superb Fw 190 had it's moment, for sure, but it was not exactly dominant by 1944. The Ju 87 was a deadly weapon in the early war, but obsolete by the middle. But the Bf 110, basically a failure at least as a day fighter, tends to be ignored by the "Germans are Uber" crowd. As does the Me 210, the He 177, Ju -188, the Do 217, and basically all their later war bombers and heavy fighters. V-1 and V-2 were sophisticated terror weapons, but you can't win a war through random terror strikes against civilians.

The Nazi state was built on a flawed, demented concept. This distorted everything they did. Maybe they would have done better if they hadn't wasted so many resources systematically murdering people in death camps. They did make slave labor work for a while, but mysterious failures in the quite impressive Panther tanks can be traced back to sabotage by those same slaves. It's not a war-winning strategy in the long run. And while yes they were sophisticated, and very advanced in certain fields like Jets and large rockets, they weren't the top or the best at everything, in fact they had some rather ghastly failures (Enigma maybe the biggest of all, aside from strategic blunders largely due to their political system). Their delusional doctrine of superiority lingers though, like a virus.
 
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Even the sophistication of their later tanks worked against them in the harsh conditions of the Eastern Front, where long distances taxed that equipment.
 
Thumpalumpacus said:
Even the sophistication of their later tanks worked against them in the harsh conditions of the Eastern Front, where long distances taxed that equipment.
Click to expand...

Also worth pointing out, the Soviets were making very formidable tank wrecking mechanical beasts of their own.

SU-100 - Wikipedia

en.wikipedia.org

According to Wikipedia: "The gun was excellent, being able to penetrate the Tiger I at 2 km with APCBC rounds while its APHE rounds could penetrate a max of 218 mm of armour"

See also: IS-2 - Wikipedia
 

Wild_Bill_Kelso said:
Especially when some poor slave being worked to death back in Germany had very cunningly and bravely put stuff in the hydraulic lines...
Click to expand...

Yeah, I wasn't arguing that that Teutonic sophistication was the only factor working against the Germans. I was simply pointing out how on the Eastern Front it made for additional difficulties.
 
Thumpalumpacus said:
Even the sophistication of their later tanks worked against them in the harsh conditions of the Eastern Front, where long distances taxed that equipment.
Click to expand...
A Panther or a Tiger needed a major overhaul at 5,000 miles. On 6 June 1944 many of the M4 Shermans that hit the beach in Normandy already had over 5,000 miles on them and were good for many more.
 
The Type 93 was ship launched only. But most of what you wrote is accurate.

Russia was able to prevail because they had massive support of the USA, we provided them with millions of tons of munitions, thousands of aircraft, thousands of tanks and 600,000 trucks.

The US mobilized the Soviet army. It was the logistics that allowed the Soviets to win. That and their utter disregard for human life. They were very happy to trade millions of lives to run the Germans out of bullets.
 

That's mostly true, and the Soviet regime, as evil in many ways as the Nazis, did have disregard for human life in general. But I am not sure the massive losses are entirely down to that. The Germans invaded by surprise, under cover of a treaty (the two countries having not that long before brutally invaded and divided up much of Eastern Europe between them), and launched a massive invasion in a war of annihilation, maybe the largest and most violent the world has ever seen, aimed strait at their two main cities of St Petersburg (then Leningrad), and Moscow, as well as at their oil producing region. They started the war at a huge deficit in terms of training, quality and modernity of equipment, and industrial base. Some of this due to Stalin's own murderous policies decimating the armed forces leadership just prior to the war. They scrambled to catch up, and we helped them hold the line during that process, but they did indeed catch up. They built a massive number of quite good military aircraft during the war, among other kit.

The help that we and the British provided them was enormous, and did help them stabilize the situation in some of the most ghastly early fighting (where many of the losses were suffered). But I don't think the US can take credit for the courage of the defense of Leningrad and Moscow, and the gigantic, staggering Soviet victory at Stalingrad in late 1942, from which the Germans never really recovered, was primarily down to Soviet troops, Soviet planning, Soviet ruthlessness, and Soviet weapons - including the Yak-1, the Il-2, and in particular, the PPsh-41 'burp gun', the Katyusha rocket, and the T-34, all indigenous Soviet inventions as far as I'm aware. All of these weapon systems were decisive in the counter-attack, almost as much as the masterful strategy which took advantage of Nazi ideological blind-spots and knack for self-delusion.

Most of the tonnage of US and UK Lend-Lease to the Soviets, came after Stalingrad was already over. 3,000,000 tons up to the end of 1942, vs 14,500,000 tons from 1943-45.

They can also take credit for moving most of their industrial base over the Urals.

We can also take note that the majority of the German war machine was fighting in the East, certainly until mid-1944.

The Russians may be the villains today with current events, but we owe them a massive debt from WW2, not the other way around. We did help with all the equipment and supplies we sent, quite a bit, but I don't think it's honest to entirely take credit for their victories.
 
Not arguing the Valor of the Soviet soldier. Of course with a commisar ready to shoot you if you don't charge the machine guns there really wasn't much of a choice.

And yes, we do owe them a debt of gratitude for their sacrifice, without it the war would have lasted a lot longer.

However, it was their utter disregard for human life that is responsible for the 25,000,000 killed.
 

The Germans were coming in with a policy of extermination. With the largest and most modern army in the world at that time. The US has never faced such a threat. Just a little perspective.
 
My favorite Russian piece in the game "Panzer Blitz" by Avalon Hill.
 
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