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

Calum Douglas said:
Nicknick said:
I don’t believe, that the modifications have been well documented and many planes crashed and many racers died. On the other hand, it seems like the unlimited class came to an end and if there is any chance to write a book about it, it is now. No one has to keep their secrets without being able to race.

As said, I would really like a book about all the piston engine concepts which existed on the drawing boards by the end of the war (and somewhat later) but never made it into production.
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Please email Rolls-Royce Heritage Trust, and ask them when they are going to reopen any of their archives, until they do, its going to be impossible to write such a book.
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Why did they close the archives to the public?
 
Calum Douglas said:
Upcoming Lecture Programme:

27th April - Cambridge, UK. Royal Aeronautical Society. (In person and online feed, email David to arrange the feed).
www.aerosociety.com

Cambridge Branch: The Race for horsepower WWII, Callum E Douglas

Members, aerospace professionals and aviation enthusiasts are invited to the Cambridge Branch's Lecture, which will focus on "The Race for horsepower WWII".
www.aerosociety.com www.aerosociety.com

17th May - Oxford, UK. Reaction Engines Ltd (private lecture to company personell only, closed to public)

20th June - London, UK. Institution of Mechanical Engineers. (In person).
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If you see Alan Bond at Reaction Engines - not sure how often he's there these days - tell him I said hi!
 
Live discussion at Military Aviation History, but unfortunately I have to get ready for a birthday party. I will watch again over this long weekend.

- YouTube

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fightingirish said:
Live discussion at Military Aviation History, but unfortunately I have to get ready for a birthday party. I will watch again over this long weekend.

- YouTube

Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.
www.youtube.com www.youtube.com
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I might have to put some of the original documents online because the yellow highlighting i "helpfully" made seems to have made it very hard to read the letters after it was squashed down on the screen.
 
Clearly we need to hack all archives and assign a clone Calum to cover each and every WW2 aero engine! (A man can dream, right?)

I also clearly need to somehow become an employee at Reaction Engines Ltd. for the day of 17 May.
 
MAN (the large engine devision) presented an ignition device for very large gas engines which looked quite similar to the ones showen in the presentation. A small, hot prechamber was used for autoignition of natural gas which worked without a spark plug during normal operation, thus reducing the maintanance cost and reducing NOx. I'm not totally sure about it, but I believe it had a small additional valve for feeding fuel rich charge into the chamber.

There was an article in the MTZ about it, don't remember when....
 
Hi Paul,

overscan (PaulMM) said:
View: https://www.youtube.com/watch?v=QailgWUZ1XE
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Thanks for the link, highly interesting! :)

At 36:30 min, Calum mentions that the test results for the Hurricane and Spitfire at 30000 ft gave speeds 20 mph slower than expected. From the test reports at wwiiaircraftperformance, considering the steep drop of speed with increasing altitude in that region and the experimental errors and various unknowns (propeller performance, exhaust thrust) involved, I'm a bit surprised that they even managed to detect what I'd have considered a rather small difference :-D

Regards,

Henning (HoHun)
 
For general info I have set up a local distribution and stock arrangement to sell The Secret Horsepower Race directly, and bought a small stock level to start. This means people can now buy direct from me which gives me very close to 10x return per book that I get if you buy from Amazon.

This works well or not so well depending on where you are in the world as shipping costs are mad these days (and the book is over the 2kg threshold between parcel and "large parcel", but its massively beneficial for me if you can buy direct. Delivery is only by tracked courier with signed for reciept.

Link below:

https://www.calum-douglas.com/

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Calum,

I work for a book publishing company. In 2007, the U.S. Postal Surface ended "Surface Mail," also called "Sea Mail." This resulted in the loss of 99% of our foreign customers overnight. The USPS cited higher costs for the decision. Just prior to this, many pounds of books could be sent from the U.S. to Australia for little money. It would take 4 to 6 weeks to get there. I think another explanation for the loss of Surface Mail is in order. It was around this time that electronic reading devices for ebooks were being offered in stores. Pushing the book buyer, especially in foreign countries, to buy these devices was the goal.
 
edwest4 said:
Calum,

I work for a book publishing company. In 2007, the U.S. Postal Surface ended "Surface Mail," also called "Sea Mail." This resulted in the loss of 99% of our foreign customers overnight. The USPS cited higher costs for the decision. Just prior to this, many pounds of books could be sent from the U.S. to Australia for little money. It would take 4 to 6 weeks to get there. I think another explanation for the loss of Surface Mail is in order. It was around this time that electronic reading devices for ebooks were being offered in stores. Pushing the book buyer, especially in foreign countries, to buy these devices was the goal.
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Yes its actually got to the point where I HAVE to make my next book under 2kg including packaging, otherwise you basically can`t economically post it outside of a 1000mile radius of the UK. If it was 100g lighter the cost goes down about 3x.

What I`d really like to do with some of these "cost increases", is say ok, so WHO has the money at the end of the chain then? and trace it back, I bet in 95% of cases it doesnt go to the person/firm/operation which claims they need to recoup operating costs.
 
Trident said:
The mind boggles... lightweight book construction. Honeycomb structures for the covers? Isogrid stiffeners? Talk about an engineering book :)
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The easiest way to lighten a book's weight is to reduce the page count and that in turn is easiest to do by eliminating any waste of space. In case of an A4 page, a text-only page can easily vary in character count (in existing books) from less than 5000 to over 10,000. The worst I have seen is less than 3000 characters. 10,000 characters is very doable without jeopardizing readability, but it does require careful selection of fonts and overall typography.
 
Pasoleati said:
In case of an A4 page, a text-only page can easily vary in character count (in existing books) from less than 5000 to over 10,000. The worst I have seen is less than 3000 characters. 10,000 characters is very doable without jeopardizing readability, but it does require careful selection of fonts and overall typography.
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Good point.
When I received Calum's The Secret Horsepower Race book I compared it with the Vee's For Victory! book I already had and noticed a considerable difference in character density.

TSHR text-only page has about 5500 characters (spaces included), while VFV has about 8700 characters.
That's a big difference, caused mainly by different text column width (VFV has less white per page width), different font, and different line spacing.

Paper quality obviously also has some impact on weight.
 
Nicknick said:
MAN (the large engine devision) presented an ignition device for very large gas engines which looked quite similar to the ones showen in the presentation. A small, hot prechamber was used for autoignition of natural gas which worked without a spark plug during normal operation, thus reducing the maintanance cost and reducing NOx. I'm not totally sure about it, but I believe it had a small additional valve for feeding fuel rich charge into the chamber.

There was an article in the MTZ about it, don't remember when....
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Uniform combustion process (no heat sink) dictates the Nox production (discussed somewhere else in this forum). This process of having a hot preburner chamber is one popular way of solving this issue.
 
One solution is to have Print on Demand here in the Americas. Send the book across the sea digitally and then have all the copies printed here. PoD can be done quite badly (e.g. Specialty Press) or quite well (e.g. Aeronaut Books or Detail & Scale). While maybe still not up to the quality of a book printed at its source, I've been quite satisfied with the PoD books that I've gotten in the States.
 
My company is very wary of Print on Demand. We tried one service but the final book used a paper stock that was not good enough. The reproduction quality was not the same as the 60# Offset paper we use. The cover did not reproduce very well. I regularly get book quotes from printers, but even with a low price quote, we require samples. If the samples aren't high quality, that particular printer is rejected.
 
gatoraptor said:
One solution is to have Print on Demand here in the Americas. Send the book across the sea digitally and then have all the copies printed here. PoD can be done quite badly (e.g. Specialty Press) or quite well (e.g. Aeronaut Books or Detail & Scale). While maybe still not up to the quality of a book printed at its source, I've been quite satisfied with the PoD books that I've gotten in the States.
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Aeronaut books are of horrible quality! The paper is of bad quality, there is only glued binding and the printing quality is so poor that many technical drawings are illegible. I have Aeronaut's properly printed book on Boelcke and the difference is massive.

Some Osprey reprints are also now PoD and again, much inferior compared to the original prints.

I have bought several British armour books by P. M. Knight. Since they are mostly text, the quality is decent but the illustrations are again substandard.
 
TomcatViP said:
Uniform combustion process (no heat sink) dictates the Nox production (discussed somewhere else in this forum). This process of having a hot preburner chamber is one popular way of solving this issue.
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@TomcatViP

Not really, as long as the mixture in the pre chamber is richter than in the cylinder, there will be higher temperatures involved and a local hot spot with NOx. The ideal solution would an entierly homogenous mixture all over the combustion chamber, but this is hard to ignite, at least when its lean enough to prevent NOx formation. There are however some experimental ignition systems which could do that. Another option are homogenous auto ignition or adding a small amount of hydrogene by fuel reforming.

BTW: We need a design challange for a lightweight book....
 
Wurger said:
Sienar, in "Wunibald Kamm - Wegbereiter der Modernen Kraftfahrtechnik", there are no mention to Messerschmitt`s rotary-valve aircraft engine being passed to Kamm`s FKFS. There was a 1936-1938 experimental 2 stroke gas 1-cylinder engine, whose development was canceled, but with ball ("kugel") exhaust valve. I recall that Messerschmitt toyed with turbojets, too.
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Btw, a really great book ...
 
Calum Douglas said:
Well after a skim of the files the VERY short version of the Bristol turbocharger research is that all their turbos were designed by the R.A.E, not Bristol, although Bristol appear to have done a pretty fair amount in terms of manufacture and development. All this work basically stopped in or about 1927 in England for reasons I`m not entirely certain of but appear to be a "tipping point" where the continued failure to develop a really reliable and simple turbo product was overtaken by the development of very reliable gear driven compressors which had "acceptable" performance. Jimmy Ellor did most of the engineering work on these turbochargers at the R.A.E, before he was later poached by RR.

The signs are that British research on turbos was probably roughly equal to the early efforts in France and later the USA, the USA eventually winning out by virtue of perseverance on the concept of the exhaust driven turbine. There was a fair bit of turbocharger stuff done in WW1 in England at the R.A.E. or "the factory" as it was then known. It looks like most of this was done on the RAF.26T 2-stroke aero engine.
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Calum, in your book on page 422 you show two very interesting diagrams by Kosche of ideas of further developments of the Jumo 213 J. The lower diagram is very well comprehensible as a turbocompound version of the 213 J (very elegantly packed). The upper diagram with its contra-rotating props is decribed as "Brennkammermotor" (engine with combustion chamber). Would it have worked in a similar way like the Nomad which could use a combustion chamber for additional power or similar to the Wärtsilä Hyperbar engine of the Leclerc tank? However it does not seem that the exhaust gases are used for driving a turbine as they directly flow to thrust ejectors.
 
Pasoleati said:
Aeronaut books are of horrible quality! The paper is of bad quality, there is only glued binding and the printing quality is so poor that many technical drawings are illegible. I have Aeronaut's properly printed book on Boelcke and the difference is massive.

Some Osprey reprints are also now PoD and again, much inferior compared to the original prints.

I have bought several British armour books by P. M. Knight. Since they are mostly text, the quality is decent but the illustrations are again substandard.
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Different PoD printers may do the same book to different quality standards. I've had no complaints with any of the Aeronaut books I've ordered from Amazon in the U.S.
 
Something to consider, with regard to page count and font size/spacing, is the age demographic of the sector in question. I have to consider very seriously, whether I buy it or not.

Seriously placing the future of the printed book in question and it is not a positive move. My neighbour upstairs has three kindles. She bought 2 and one was sent as a replacement and she can use none of them. Rubbish standards by any measure.

Take into account the almost impossibility of putting the illustrations of Horsepower race (Abbr) and you have an untenable situation. Agree re the PoD aspect, potentially a worthwhile exercise but leaky standards mean also, at the moment, untenable.
 
That was quite negative. My company has been around for a long time. We are always keeping track of any changes going on. In this particular market, there is consistency. If a book is desirable it sells out. It may or may not be reprinted, which is always a personal decision by the publisher. The so-called "secondary market" is run by individuals who watch when books go out of print and raise the prices way beyond anything reasonable. So will there be people who can't afford a lot? Yes - always. My upper limit is usually $50 but I have paid $100 to $200 for certain publications. It's rare but I've done it. I felt lucky to get a copy of Brett Gooden's Natter book for $90.
 
Foo Fighter said:
Something to consider, with regard to page count and font size/spacing, is the age demographic of the sector in question. I have to consider very seriously, whether I buy it or not.

Seriously placing the future of the printed book in question and it is not a positive move. My neighbour upstairs has three kindles. She bought 2 and one was sent as a replacement and she can use none of them. Rubbish standards by any measure.

Take into account the almost impossibility of putting the illustrations of Horsepower race (Abbr) and you have an untenable situation. Agree re the PoD aspect, potentially a worthwhile exercise but leaky standards mean also, at the moment, untenable.
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I did a survey on my facebook page early in the writing process (about a year before publication), financials have changed a bit since then, but of a sample of about 40 people, only one person said they wanted an electronic version.

Maybe now it would be..2 or 3, but generally we had little but complaints about the electronic version. People with older kindles found it didnt display correctly, and those who could complained that they had to "scroll about" the pages to read it. Apparently hoping that we would have funds to completely reformat the entire book and index just to make it convenient for e-books.

All the 1 and 2 star reviews of the book on Amazon are from people with old kindles who didnt like it (and the only person who have a 3 star review said it was a wonderful book but were annoyed as the courier dropped the box and crumpled a corner :rolleyes: , thanks for that important review of the book!). You could of course say "well thats because the e-book version was not done very well", that may be so, but that is nevertheless what happened in reality when quite a large fairly respected transportation publisher did it with my book.

Anyway, so on balance I`m not about to do any e-book adventures. I think to make it workable you`d have to set out to do e-book only and format everything and design everything around it from the start, or have a huge initial budget and absorb a doubling of your typesetting cost.

For me the clear lesson is that all future books need to be about 1.9kg including packaging to be viable from the UK to overseas.
 
Basil said:
Calum, in your book on page 422 you show two very interesting diagrams by Kosche of ideas of further developments of the Jumo 213 J. The lower diagram is very well comprehensible as a turbocompound version of the 213 J (very elegantly packed). The upper diagram with its contra-rotating props is decribed as "Brennkammermotor" (engine with combustion chamber). Would it have worked in a similar way like the Nomad which could use a combustion chamber for additional power or similar to the Wärtsilä Hyperbar engine of the Leclerc tank? However it does not seem that the exhaust gases are used for driving a turbine as they directly flow to thrust ejectors.
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The upper sketch is somewhat mysterious, but basically what is being suggested is that under certain flight conditions the exhaust ejector effect produces a higher thrust efficiency compared to a turbo. Here Kosche suggests a mechanical 2 stage blower and a 213J with ultra high valve overlap and exhausts which are shaped to provide thrust. Here the engine is being used in a way which is possibly half-way between a normal piston aero engine and a turboprop in flight-speed/efficiency envelope. The power loss driving the oversized mechanical supercharger would be offset by the fact the flow from the supercharger is leveraged by the fuel chemical energy in the combustion chamber so that a lower amount goes to the prop than usual but a higher amount to exhaust thrust than usual.

I cannot comment on if this was thermodynamically practical or not.
 
Calum Douglas said:
but of a sample of about 40 people, only one person said they wanted an electronic version.

Maybe now it would be..2 or 3, but generally we had little but complaints about the electronic version. People with older kindles found it didnt display correctly, and those who could complained that they had to "scroll about" the pages to read it. Apparently hoping that we would have funds to completely reformat the entire book and index just to make it convenient for e-books.
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Is there an electronic version actually available? I didn't think there was. I would like such a copy as it makes it easier while travelling.
 
Calum Douglas said:
The upper sketch is somewhat mysterious, but basically what is being suggested is that under certain flight conditions the exhaust ejector effect produces a higher thrust efficiency compared to a turbo. Here Kosche suggests a mechanical 2 stage blower and a 213J with ultra high valve overlap and exhausts which are shaped to provide thrust. Here the engine is being used in a way which is possibly half-way between a normal piston aero engine and a turboprop in flight-speed/efficiency envelope. The power loss driving the oversized mechanical supercharger would be offset by the fact the flow from the supercharger is leveraged by the fuel chemical energy in the combustion chamber so that a lower amount goes to the prop than usual but a higher amount to exhaust thrust than usual.

I cannot comment on if this was thermodynamically practical or not.
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Great explanation, thanks! Would have needed some sort of variable valve timing, I suggest (which was already on the drawing board for some aircraft engine designes at BMW, Lycoming, Pratt & Whitney).
 
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II think the actual book weight limit is about 1.8 kg as a pretty sturdy packing is achievable within 200 grams.

My kitchen scale is limited to 2 kg and weighing the book failed, but it is not probably much above 2 kg. Thus the weight reduction doesn't need to be more than approximately 15 %. Very easy to achieve with slight changes in layout/font.
 
I don't remember whether it is mentioned in the book, but: According to a Finnish source, the DB 605 was totally unsuitable for fighter training due to the stresses imposed. For example, the source says "Especially the frequent pull-outs (from dive) stressed the sensitive engine". Did Germans report anything on this? Were there any reports of comparable weakness regarding the Jumo, Merlin or the Allison? Apparently due to engine structure bending dresses during the pull-outs.

By the way, in the first year of ops in Finland (=1943), the longest life obtained from a DB 605 was 86 running hours. And that with the Start und Notleistung disabled. I would say: a PoS for an engine.
 
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Calum ahoy! I just received a report of damage investigation on one DB 605. Total running hours was 29 hours 30 minutes. Description of damage: Crankcase cover and crankcase sheared at the location of cylinders 1 and 7. Conrods of cylinders 1 and 7 broken and the appropriate big-end bearing seized.

The squadron commander states that the 10-hour training program stresses engines more than combat service due to oil starvation of forwardmost bearings during pull-outs.

To me this sounds like a very poorly designed engine.
 
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Calum Douglas said:
Yes although its not terribly cost effective and I think only works via an online access platform.

The Secret Horsepower Race - Western Front Fighter Engine Development | at Mortons Books

www.mortonsbooks.co.uk www.mortonsbooks.co.uk
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The Pocketmags editions of Morton's books require a specific reader and are stored in the cloud, so you don't get an epub or PDF file you can save somewhere or put on your Kindle.

I've still purchased some titles, due to delivery costs, but they ought to be cheap based on these limitations, being the same price as the beautiful printed book is not sensible (unit cost of the ebook should be near zero)
 
Pasoleati said:
Calum ahoy! I just received a report of damage investigation on one DB 605. Total running hours was 29 hours 30 minutes. Description of damage: Crankcase cover and crankcase sheared at the location of cylinders 1 and 7. Conrods of cylinders 1 and 7 broken and the appropriate big-end bearing seized.

The squadron commander states that the 10-hour training program stresses engines more than combat service due to oil starvation of forwardmost bearings during pull-outs.

To me this sounds like a very poorly designed engine.
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You need to keep in mind, that this engine was built out of cheap materials (whatever was available in the moment) and often assemblied by forced labour, so it is not to suprising, if it doesn't have a lot of reserves.
 
I don't know whether this has been discussed yet, but what advantage was the Rolls-Royce Goshawk supposed to really have over the Kestrel of identical displacement? I can't figure out what advantage evaporative cooling was supposed to provide, considering the obvious increase in complexity. Surely the MoD should have realized that a larger engine would be needed soon, and kudos to R-R for figuring that out and developing the Merlin as a private venture.
 
Nicknick said:
You need to keep in mind, that this engine was built out of cheap materials (whatever was available in the moment) and often assemblied by forced labour, so it is not to suprising, if it doesn't have a lot of reserves.
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That's the usual excuse, in my opinion. For example, in 1944 the Cyclones in the F2A had about 11 times higher time between failures. And by 1944 the original supply of spares etc. had been dried up for several years and some Cyclones could have parts from Soviet M-62 engines fitted instead of originals. So even with quite up to date factory support the DB had very short service lives, even shorter than those Soviet engines, for which Finns had no steady supply of parts or even repair manuals. And the Bristol Mercuries in Blenheims had also several times higher TBF. And again, factory support had ceased by 1941.

If you read the damage description, it is very obvious that the "damage mechanism" has nothing to do with materials used.
 
Nicknick said:
You need to keep in mind, that this engine was built out of cheap materials (whatever was available in the moment) and often assemblied by forced labour, so it is not to suprising, if it doesn't have a lot of reserves.
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That's the usual excuse, in my opinion. For example, in 1944 the Cyclones in the F2A had about 11 times higher time between failures. And by 1944 the original supply of spares etc. had been dried up for several years and some Cyclones could have parts from Soviet M-62 engines fitted instead of originals. So even with quite up to date factory support the DB had very short service lives, even shorter than those of the Soviet engines, for which Finns had no steady supply of parts or even repair manuals. And the Bristol Mercuries in Blenheims had also several times higher TBF. And again, factory support had ceased by 1941.

If you read the damage description, it is very obvious that the "damage mechanism" has nothing to do with materials used
 

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