The Secret Horsepower Race by Calum Douglas (and piston engine discussion)

I've got a question Calum. My perception, from all I've read and the comments here is that the US was the only nation with a serious effort on turbochargers going on between the wars. Both German and Japanese efforts during WW II appear to be late and less than successful and Britain doesn't seem to have looked at it at all. Is this perception correct?
Sort of, it terms of the actual "results" in aircraft thats broadly correct, but once you look at the R&D files in both Britain and Germany, it gets a bit more difficult understand at first.

There was actually a reasonable amount going in in Britain on turbos in the inter-war period. Germany too.

I have a couple of small files on Japanese turbos and I think they really did nothing at all on them what-so-ever until
they were actually IN the war.

It is more complicated than this, but the wartime turbos in Germany and Japan were basically scuppered because the casings kept cracking and the blades were only permitted a max metal temp of 600 degrees C (the gas coming out the cylinder head would be between 950 and 1080 deg C). So BMW ended up doing all that work on hollow blades with forced air cooling. This actually worked but by the time it was all done they`d lost a couple of years and "that was that".

(there were flight tests of turbochargers going on at the R.A.E. in England in 1926)
Thank you for that response. It does make the picture a bit more clear.
 
Wrt to japanase Turbos, or more probably the lack of it, wouldn't that be more related to Japanese low octane fuel that prevented efficient high boost settings (superchargers were then more practical).
A turbocharged engine gives more power at the same BMEP (which determines octane/PN requirements) than a mechanically supercharged one.
 
The variable I am concerned with is temperature.
Turbo + low grade fuel + weak metallurgical performances is a bad combo.

What you might want in that case is increasing physical capacity and go through only a low boost, compact solution, such as with a supercharger.
 
@Dagger : thank you. I don't understand however what was the point of a multi-pages archive document when a quick internet search brings a fairly accurate results wrt octane level in WWII Japanese aviation fuels.

As I have said earlier, if they had metallurgical problems and low level of octane, using high boost settings with a turbo was not the easiest path to go.
 
The Japanese had high temperature metals according to the U.S. Navy Technical Mission Reports. I think this is a case of assuming they did not.
 
I will definetly buy the second edition if it includes more on German engine development. Calum's latest Tweets point only to british endeavors.
 
Given that including all information on all engines would make the book too big I wonder if it would be feasible to do a separate series of smaller monographs on individual engine types. For example the Jumo 213 or the Bristol Hercules.
 
The Japanese had high temperature metals according to the U.S. Navy Technical Mission Reports. I think this is a case of assuming they did not.
Everyone had high temperature metals, it depends how MUCH and WHEN. :) Early in the war the Japanese were not doing much with turbochargers, but had lots of Nickel, later they had not much Nickel but were trying to do a lot with turbochargers, jets and rockets... so...

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Thank you Calum. Like the Germans, the Japanese were working with substitute metals toward the end of the war.
 
I ordered my copy a few months ago from the main French aero bookstore, but was told it was not in stock and that I will receive it as soon as it is back. I assume I will have the second version.

Otherwise, I saw in this thread that if it will mainly be about Great Britain, the United States and Germany, there will be elements on Japan, Italy and the Soviet Union, and a little bit of France with Hispano-Suiza.

In the book, will there still be some elements on the reasons for the French failure to develop the turbocharger for aircraft (while this development was successful for ships)?

In my list (probably not exhaustive ) of turbocharged engines from France, I have :

-Breguet XIV (light bomber). In 1918, a Rateau turbocharger was mated to a 320 hp Renault 12-Fe engine. In 1923, this engine was mounted on a Breguet XIV A2. 16 planes are delivered to the 34th aviation regiment of Le Bourget. But this engine assembly did not pass the 10-hour endurance test.

-SPAD XIII (fighter). 1918 or 1919? Prototype n°706, HS 300 hp, Rateau turbocharger.

-Nieuport NiD-29 (fighter). 1919. Rateau Turbocharger. Altitude world record at 9520 m in 1919. The same aircraft reached 10,600 m in 1921 (record not approved because the landing aerodrome was different from that of take-off...).

-Bernard HV-120 (Schneider cup racer). At the end of 1929, the HV 120 received a Hispano-Suiza 1800 hp turbocharged engine (the aircraft was destroyed during a test on July 30, 1931 on the Etang de Berre).

-NiD-450 (Schneider cup racer). At the end of 1929, it received a Hispano-Suiza turbocharged 1800 hp engine.

-NiD 622 (fighter). 1931. Single-seat Sesquiplan fighter (No. 289) fitted experimentally with a mechanically driven Farman-Waseige two-stage turbocharger which was flight tested from December 1931 to June 1932.

-Dewoitine HD-41 (Schneider cup racer). 1931. Lorraine Radium engine. Dewoitine was the only one to receive this engine, which turned on the bench. Lorraine offered to make racing engines. In July, the first copy was sent to the Dewoitine factory in Toulouse (Haute-Garonne) for testing. The engine on the bench did not exceed 2,000 rpm. In order to understand the reasons, Maurice Barbarou decided to push the engine, which broke at 3,000 rpm. Different technical solutions in terms of supercharging to counter this problem were then imagined and tested: (...), classic Rateau turbocharger (powered by the exhausts), (...). Nothing helped: the desired power (2,300 hp) was not there. In August, the engine's fate was sealed.
 
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I ordered my copy a few months ago from the main French aero bookstore, but was told it was not in stock and that I will receive it as soon as it is back. I assume I will have the second version.

Otherwise, I saw in this thread that if it will mainly be about Great Britain, the United States and Germany, there will be elements on Japan, Italy and the Soviet Union, and a little bit of France with Hispano-Suiza.

In the book, will there still be some elements on the reasons for the French failure to develop the turbocharger for aircraft (while this development was successful for ships)?

In my list (probably not exhaustive ) of turbocharged engines from France, I have :

-Breguet XIV (light bomber). In 1918, a Rateau turbocharger was mated to a 320 hp Renault 12-Fe engine. In 1923, this engine was mounted on a Breguet XIV A2. 16 planes are delivered to the 34th aviation regiment of Le Bourget. But this engine assembly did not pass the 10-hour endurance test.

-SPAD XIII (fighter). 1918 or 1919? Prototype n°706, HS 300 hp, Rateau turbocharger.

-Nieuport NiD-29 (fighter). 1919. Rateau Turbocharger. Altitude world record at 9520 m in 1919. The same aircraft reached 10,600 m in 1921 (record not approved because the landing aerodrome was different from that of take-off...).

-Bernard HV-120 (Schneider cup racer). At the end of 1929, the HV 120 received a Hispano-Suiza 1800 hp turbocharged engine (the aircraft was destroyed during a test on July 30, 1931 on the Etang de Berre).

-NiD-450 (Schneider cup racer). At the end of 1929, it received a Hispano-Suiza turbocharged 1800 hp engine.

-NiD 622 (fighter). 1931. Single-seat Sesquiplan fighter (No. 289) fitted experimentally with a mechanically driven Farman-Waseige two-stage turbocharger which was flight tested from December 1931 to June 1932.

-Dewoitine HD-41 (Schneider cup racer). 1931. Lorraine Radium engine. Dewoitine was the only one to receive this engine, which turned on the bench. Lorraine offered to make racing engines. In July, the first copy was sent to the Dewoitine factory in Toulouse (Haute-Garonne) for testing. The engine on the bench did not exceed 2,000 rpm. In order to understand the reasons, Maurice Barbarou decided to push the engine, which broke at 3,000 rpm. Different technical solutions in terms of supercharging to counter this problem were then imagined and tested: (...), classic Rateau turbocharger (powered by the exhausts), (...). Nothing helped: the desired power (2,300 hp) was not there. In August, the engine's fate was sealed.
No idea why your French distributor said there were none in stock, we have printed over ten thousand copies in ten reprints.
I suggest you cancel the order with them, and order direct from the publisher Mortons.


The 2nd edition (the reprints only had minor typographic corrections), will not be ready for a long time, well into next year, and this is certainly not what your French distributor is waiting for as it does not even have an ISBN yet.
The book starts at the end of the schneider trophy, so I do not think will cover questions about French turbocharger use from 1918>1931. Which is probably a topic for a different book.

With respect to your question on France I can only offer the comments of Bulman (Director of Engine Development at the Ministry of Aircraft Production in Britain).

The date of this memo is unknown, but in pencil (a modern marking no doubt) "early 30`s ?" is written on the first page.

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I would suspect that the severe fluctuations in the French government between the wars may have contributed to the lack of development. "Two Roads to War" is a fascinating look at British and French aeronautical and air force developments between the wars and the effects of fluctuating government in France are clearly shown.

It's interesting just how widespread turbocharger work was in the US. It was a major factor in the diesel engines used by ALCO to compete with what EMD produced and marketed - essentially one engine with the same power as two normally aspirated engines in EMD's locomotives.
 
I would suspect that the severe fluctuations in the French government between the wars may have contributed to the lack of development. "Two Roads to War" is a fascinating look at British and French aeronautical and air force developments between the wars and the effects of fluctuating government in France are clearly shown.
I've read quite a bit about this already, but I have to say that I don't have a very clear overview yet (I started a personal file, but it is still very, very far from being exhaustive, and I admit that I do not always take the time to feed it), although I can discern a number of key episodes, like this one:
This book ("Two roads to War") could bring me other clarifications, thank you.
 
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Finally worked my way through the book... and I can only echo the general acclaim it has received, so I won't bother repeating the praise at length :)

Instead, a question to Calum: one of the most notable (and symptomatic, regarding the lack of competent guidance at the administrative level) stories to emerge from your book is the tortuous development of German pressurized high-temperature cooling. Do you reckon that earlier adoption could potentially have mitigated the bearing failures due to oil dilution that plagued Daimler engines with the C3 Fuel in 1941, much like air-cooling seemed to spare BMW's 801 from the same issue? That would kind of add insult to injury!

Thanks!
 
Finally worked my way through the book... and I can only echo the general acclaim it has received, so I won't bother repeating the praise at length :)

Instead, a question to Calum: one of the most notable (and symptomatic, regarding the lack of competent guidance at the administrative level) stories to emerge from your book is the tortuous development of German pressurized high-temperature cooling. Do you reckon that earlier adoption could potentially have mitigated the bearing failures due to oil dilution that plagued Daimler engines with the C3 Fuel in 1941, much like air-cooling seemed to spare BMW's 801 from the same issue? That would kind of add insult to injury!

Thanks!
On the youtube 'Gregs airplanes' channel he has a lengthy video on C3 and B4 fuels, great for piston engine geeks like me! IMO yes, running higher coolant temperatures would have let fuel boil out of the oil, which would help the bearings.
 
Relative to my earlier comments about ALCO's use of turbochargers, a history of the company brought up something interesting. The original turbochargers they used were built under license and were water-cooled. After WW II, when they designed a new engine, they were partnered with GE and used a GE air-cooled turbocharger from aircraft operations. That turned out to be one of the factors that led to reduced reliability of those engines and a decline in sales. They developed a replacement engine, going back to the water-cooled turbocharger they had earlier used (they had split from GE who were now competitors) and it was quite reliable, but the damage had been done and they exited production, in the USA, in 1969 while their Canadian operation, MLW, continued for a few years more before being acquired by Bombardier.
 
I know that he did mention that already, so I am adding this here to the discussion, but coolant temperature functional limits are driven by manufacturing technologies. Something Germans didn't master as much as the British and the US industry in that specific domain.

So in effect, there was no solving to be expected with a higher coolant temperature, as that they could not reach it.
 
Hi Calum,

It will be mid November now for release, as (like all the other publishers discovered) it is a rather large and complicated book to get right.
However, I have a full draft copy pdf of the German language version in final layout with all images and refernces in place, we`ve just got about... fifty or so small bits to tidy and a couple of images to tweak.

I just received my copy ... it looks great, I love the new and more legible font for the direct quotes, and printing them with a slightly "off-black" colour makes it even more übersichtlich ... not sure there's even a word for this in English! :)

It also gives the pages a bit of the magic shimmer of the two-colour printed "The Neverending Story" by Ende ... I love it!

Regards,

Henning (HoHun)
 
Hi Calum,

It will be mid November now for release, as (like all the other publishers discovered) it is a rather large and complicated book to get right.
However, I have a full draft copy pdf of the German language version in final layout with all images and refernces in place, we`ve just got about... fifty or so small bits to tidy and a couple of images to tweak.

I just received my copy ... it looks great, I love the new and more legible font for the direct quotes, and printing them with a slightly "off-black" colour makes it even more übersichtlich ... not sure there's even a word for this in English! :)

It also gives the pages a bit of the magic shimmer of the two-colour printed "The Neverending Story" by Ende ... I love it!

Regards,

Henning (HoHun)
Any early feedback on the translation ?
 
Hi Calum,

Any early feedback on the translation ?

As I already read the English original and bought the German translation only for the untranslated source quotes, I didn't actually read any of the translated text yet :) I'll have a look!

Regards,

Henning (HoHun)
Thanks, much appreciated.
 
Any early feedback on the translation ?
Hi Calum,
my ordered German issue arrived a few days ago and it is now lying wrapped under the Christmas tree, so my review will follow earliest next week.
"Danke" so far and "Frohe Weihnachten" from me.
Slán,
fightingirish
 
Hi Calum,

If you can read it all in that time-frame I will be extrememly impressed.:)
Please do let us know your opinion after reading it.

I just tried to look up some engines and couldn't find the index ... has it been omitted from the German edition?

Regards,

Henning (HoHun)
 
Hi Calum,

If you can read it all in that time-frame I will be extrememly impressed.:)
Please do let us know your opinion after reading it.

I just tried to look up some engines and couldn't find the index ... has it been omitted from the German edition?

Regards,

Henning (HoHun)
I suppose it must have been if its not there, I only had a pre-production proof document from them near the end of the process
which did have the index translated, but they had not yet changed the page numbers. I certainly did not recieve any
notification that they intended to omit it.

I`ve emailed Motorbuch Verlag to ask what the situation is.
 
Apparently it was left out intentionally.

Its not impossible that I could do it myself and put a German index on my website, would that be helpful ?

(its a big job, so wont happen tomorrow !)
 
Hi Calum,

Its not impossible that I could do it myself and put a German index on my website, would that be helpful ?

Absolutely, after having the read front-to-back, I intend to come back to it frequently in order to look up things! Very bad call by Motorbuch, it would be great if you could plug that gap (even though I fear it's going to be a truly Herculean job, if it can't be done by an automatic tool).

Regards,

Henning (HoHun)
 
Hi Calum,

Its not impossible that I could do it myself and put a German index on my website, would that be helpful ?

Absolutely, after having the read front-to-back, I intend to come back to it frequently in order to look up things! Very bad call by Motorbuch, it would be great if you could plug that gap (even though I fear it's going to be a truly Herculean job, if it can't be done by an automatic tool).

Regards,

Henning (HoHun)

They have just agreed to put it into future print-runs of the book after I do the index. I am
dissapointed this has happened.

I`ll also put on my website for existing customers, which does have the small benefit
that I can then add in custom words which may not have been in the original.

Do you have any feedback on the book content ?
 
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