Another 10000 P-36/40 aircraft?

P-39 Expert said:

Yes they did, in September 1942. Said they would now operate at 27000'. Plenty high enough to combat the Japanese.

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And the P-39 has what to do with this thread/topic?

wuzak said:

Which manufacturers would build the P-40 in Britain?

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My guess is not in Britain, but instead CC&F and CAC. The Allison Engine Company had an overhaul operation in Brisbane Australia that could be scaled up, while CC&F is just a rail away from the main plants.

When was this Allison facility in Australia started?
There is also a difference in overhauling an engine and casting crankcases and cylinder blocks. Not to mention making crankshafts and such.

Australia got there but moving up the engine timeline by several years may be more difficult than you think.

Engines seemed to be the most difficult technology of military aircraft in WW2

Schweik said:

I've read (and downloaded) every document available on WW2AircraftPerformance.org on the P-39 and P-40 (and several other planes). I was asking ThomasP for a document link or doc number because I don't have any document on the specific test ThomasP seems to have referred to for the P-40F, and if it was available I'd like to add it to my archive. His numbers basically match my own from secondary sources, but I'd still like to find the primary source for that 1943 test if it exists. I also have flight manuals for every version of the P-40 (and for several other aircraft, including two versions of the P-39).

I am always interested in any primary sources I don't already have. I'm not interested in your interpretation or analysis, no offense but your subjective analysis is obviously not credible on this issue and your opinion is already very well known here. You are obviously deeply invested in a rehabilitation of this aircraft - as I've said many times, the combat histories speak for themselves in this regard. Good luck in your attempts but I'm not going to engage with you on P-39 vs anything.

I am not averse to thread drift and have often contributed to it myself many times but it's clearly time to give a rest to the P-39 hijacking, you are not helping your cause so to speak, in fact very much to the contrary.

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Giving it a rest, I can't post anywhere anymore except the groundhog thread. Come on over and show me how my information is not credible.

P-39 Expert said:

Giving it a rest, I can't post anywhere anymore except the groundhog thread. Come on over and show me how my information is not credible.

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You can post in any thread as long as you are not hijacking it.

Schweik said:

Engines seemed to be the most difficult technology of military aircraft in WW2

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That depends on your viewpoint. Since the P-51B was 30 MPH faster than the Spitfire with the same engine, and the Spitfire was considered "aerodynamic", mastering all the ins and outs of an airframe design and then producing it wasnt easy.

The 30's and 40's saw an explosive (no pun intended) growth in engine technology.
The demand was driven both by the need for powering newer designs, but also by the opposition.
No sooner did you have a top performing engine, the enemy upgrades theirs.

So it was an ongoing process and the only greater challenge, was making enough engines to meet the airframe production.

GrauGeist said:

The 30's and 40's saw an explosive (no pun intended) growth in engine technology.
The demand was driven both by the need for powering newer designs, but also by the opposition.
No sooner did you have a top performing engine, the enemy upgrades theirs.

So it was an ongoing process and the only greater challenge, was making enough engines to meet the airframe production.

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I agree fully except it wasnt "engine technology" as a single entity but a huge range of technologies that go into an engine. All branches of metallurgy were pushed to the limits same with fuel technology, fluid dynamics, machining tech. Then you have the problem of taking the thing you have an example of and making them by the thousand starting yesterday if that's possible but today is the deadline, or you lost the race.

pbehn said:

I agree fully except it wasnt "engine technology" as a single entity but a huge range of technologies that go into an engine. All branches of metallurgy were pushed to the limits same with fuel technology, fluid dynamics, machining tech. Then you have the problem of taking the thing you have an example of and making them by the thousand starting yesterday if that's possible but today is the deadline, or you lost the race.

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I used the term "engine technology" as a catch-all, because all the contributing technologies that were involved would make for an extremely long list!
Like fuel delivery for example: perfecting the carburetor, then advancing to a form of throttle-body injection, then fuel injection all while working out a suitable delivery pressure and so on.
Add to that, finding the right fuel blend that will deliver optimum combustion while resisting detonation.

Then there were the alloys being developed for pistons, cylinder heads (and trying to find the perfect cooling fin configuration for radials), gear cases and other components, etc.

And these listed are a minute example...

My comment is on the basis of - if you read the design and production histories of say, 20 successful and 20 failed or partly failed (because delayed) military aircraft types from the era, the number one issue blocking success bar none is the engine. Design problems with the engines, delays in engine production, multiple new engines which never did become available due to prolonged issues, maintenance problems with engines, and poorly or underperforming engines.

Even aircraft which had multiple other problems usually had major problems with the engines. Of course it was also possible to make a bad airframe, but it seems like there were far more countries capable of making a pretty good fighter airframe during the war than there were countries which could produce a viable aircraft engine, equivalent to the high standards of the day.

A lot of the "advanced" metallurgy in WW2 was actually rediscovery or revival of older techniques. Especially for example with armor.

GrauGeist said:

I used the term "engine technology" as a catch-all, because all the contributing technologies that were involved would make for an extremely long list!
Like fuel delivery for example: perfecting the carburetor, then advancing to a form of throttle-body injection, then fuel injection all while working out a suitable delivery pressure and so on.
Add to that, finding the right fuel blend that will deliver optimum combustion while resisting detonation.

Then there were the alloys being developed for pistons, cylinder heads (and trying to find the perfect cooling fin configuration for radials), gear cases and other components, etc.

And these listed are a minute example...

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That is exactly what I was alluding to. The power output of the Centaurus was improved by developing a high copper alloy metal purely for its thermal conductivity for use in the cylinder head.

By repetition you get used to a different "normal". Looking at the fins of air cooled engines it is easy to think that you can machine any metal in that way, with some sort of modified saw, in fact you cant, it is much more difficult than most imagine.

Allison changed their crankcases and/or cylinder blocks at least twice.
However I don't think Allison was doing their own aluminum casting.
The 2nd time they adopted a technique that had been developed by some artists for making sculptures.
It was these new castings (with a change in heat treatment of the crankshaft) that allowed the take-off power to go from 1150hp to 1325hp and still pass the 150 hour test.

Now if this technique is not adopted by Allison (or their suppliers) until the spring of 1942(?) where does that leave anybody who wanted to license Allison engines in 1940 or 41?

I have mentioned a number of times that Wright changed the crankcase on the R-1820 a number of times, The R-1820G, R-1820G-100, R-1820G-200 and R-1820H all used different crankcases (and cranks and other parts) They also changed the method of making fins on the 1300hp and up versions.
Not by using special gang saws but by fitting folded sheet metal fins into machined slots. It was somewhat more complicated than that but that is the basic idea.
If you license an early engine not only don't you get the latest "ideas" but your production machinery won't be able to build the newer versions.

Hey Shortround6,

Do you have any specific info on what the differences were between the R-1820G and H crankcase?

Shortround6 said:

Allison changed their crankcases and/or cylinder blocks at least twice.
However I don't think Allison was doing their own aluminum casting.
The 2nd time they adopted a technique that had been developed by some artists for making sculptures.
It was these new castings (with a change in heat treatment of the crankshaft) that allowed the take-off power to go from 1150hp to 1325hp and still pass the 150 hour test.

Now if this technique is not adopted by Allison (or their suppliers) until the spring of 1942(?) where does that leave anybody who wanted to license Allison engines in 1940 or 41?

I have mentioned a number of times that Wright changed the crankcase on the R-1820 a number of times, The R-1820G, R-1820G-100, R-1820G-200 and R-1820H all used different crankcases (and cranks and other parts) They also changed the method of making fins on the 1300hp and up versions.
Not by using special gang saws but by fitting folded sheet metal fins into machined slots. It was somewhat more complicated than that but that is the basic idea.
If you license an early engine not only don't you get the latest "ideas" but your production machinery won't be able to build the newer versions.

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Wasn't there also an improvement in fuel that allowed the increase from 1150hp to 1325hp?

Allison improved the heat treatment by work-hardening (peening) and tempering the crank case and (steel) crank shaft, and then they coated the bearings with a metal called indium. All of this improved the performance at higher RPM and boost pressures. Indium is still apparently used as an alloy in engine bearings for high speed engines.

This kind of dips into an area where I have some expertise, perhaps people might find some of this interesting.

The crank shaft, cam shaft, and cam slider date back to Archimedes at least, but only on the scale of simple toys. They were significantly improved during the late medieval period in northern Italy and Southern Germany as a means of converting water wheel power (and to a lesser extent, wind mill power) to create a variety of industrial machinery, semi-automated sawmills, wire pulling mills, paper mills, fulling mills, (so called Catalan) forges and automated trip hammers. In the then Free Cities of Augsburg, Strasbourg Nuremberg and Prague, the first metal examples of cam shafts, sliders, and crank cases were created for the use in clocks and clockwork machines (automata) in the early 15th Century. These water powered, wind powered and spring / weight powered machines were still in wide use through the 19th Century.

The tempering processes they revived for these purposes also date back to the 15th-Century in what was then the Free City of Augsburg, an ancient armor production center where the famous Helmschmied family first made their name, and where Messerschmitt (which name means, knife maker or sword maker) was incorporated in 1926, and one of the places where the Bf 109 was built in WW2. In the 14th century, armorers in Milan figured out how to make a 'harness' (suit) of good quality (largely slag free) medium carbon (about .6%) steel, and then in 15th Century armorers in Augsburg worked out how to properly heat treat large pieces of armor like breast plates and helmets. This made the metal more springy, and effectively doubled the 'toughness' of a piece of steel. Very tricky to properly treat something as large as say, a breast plate, but the craft guilds in Augsburg figured it out. The result of this was that armor could be made half as thick, so a 3mm armor 'proofed' plate was as strong as a 7mm iron plate. Making it much lighter (35 lbs vs 80 lbs for an entire head to toe harness or 'suit') and therefore easier to wear - important at the time due to the rapid proliferation of firearms and super powerful crossbows. The efficacy of this type of armor was far superior to armor that came centuries later such as during the 30 Years War (17th Century), by which time the technology had been mostly lost.

As the political power shifted dramatically in Europe in the 16th Century, many of the armorers from Augsburg were hired by the Holy Roman Emperor to work in his workshops in Austria, and then were in turn hired away by Henry VIII to set up his new arms manufacturing center at Greenwich, England. In 2017 NOVA sponsored a very carefully done experiment where a harness of Greenwich armor from that shop was meticulously copied, using the old processes, and it proved capable of deflecting a 3000 joule musket ball at 20 feet. During WW2 these same armor hardening and tempering techniques were used for aircraft and tank armor, for the same reasons (greater strength for far less weight).

Tempering processes pioneered in Augsburg in the early 15th century were applied to springs, gun barrels, and a wide variety of other devices and machines in the next 120 years or so, and became the basis of the first pocket watch (in 1510 in Nuremberg) and the wheel-lock mechanism for firearms (probably also in Nuremberg around the same time). Rifled firearm barrels, made of the same kind of tempered steel, were 'officially' invented in Augsburg in 1498, though Augsburg town council records mention 'screwed' gunbarrels being confiscated from traditional shooting contests as early as 1420, (because they were considered cheating - but they kept the confiscated guns in the town armory!) Another record indicates a cutler named Gaspard Kollner in Nuremberg (his name indicates he was originally from Cologne) and an armorer named August Kotter in Augsburg who both claimed to invent the first spiral rifling around the same time, in 1520.

When people look at Germany in the early to mid 20th Century, there is a curious mix of highly skilled and creative craftsmanship with this whole 'Prussian' militarism and harsh discipline. These two things don't really go together, or they don't grow together anyway. The former originates in these little 'free cities', many of which remained independent republics until the 19th Century, and the latter originates largely with the Crusader State of the Teutonic Knights in what is now northern Poland and the Baltic States. These two 'estates' within German speaking lands did not get along, and actually routinely went to war with one another. But the somewhat chaotic nature of the Free Cities in the old "Holy Roman Empire" was reigned in during the new German Empire, and the two estates were at last fused together, the former in service of the latter, which made for a formidable combination, but for not altogether great results as we know.

P-39 Expert said:

Wasn't there also an improvement in fuel that allowed the increase from 1150hp to 1325hp?

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yes the higher octane fuel. The improvements to the engine and the higher octane fuel went together.

If I will be forgiven a further derail and sidetrack, here are a couple of videos showing the mobility you have in proper tempered steel 'Augsburg style' armor that is also properly fitted:



As you can see, it's not quite the lumbering depiction we always get in popular genre media.

Hey Schweik,

Thanks for the info - on both metallurgical subjects.