Engine design as related to airplane power : with particular reference to performance at varying alt

[MiTasol]

Because some of us are either younger and do not have a knowledge of the basics of Engine design and therefore do not know how that directly affects airframe design, or are who are older but do not have the vast hands on experience that others have, I am posting this copy of the above publication.

According to Worldcat (a catalog of many of the worlds top libraries) the original was printed in 1942, there was a 1943 revision and 1949 revision. This particular copy was printed in Australia in 1945 but appears to be essentially a copy of the 1943 US manual.

The 1942 version in black and white can be found at Some fundamentals of aircraft engine design (with particular reference to the requirements for performance at varying altitudes) but is a Google scan with all the issues that go with those publications.

The 1943 version in black and white can be found at Engine design as related to airplane power : with particular reference to performance at varying altitudes. but is a Google scan with all the issues that go with those publications. In general it is clearer than my copy.

My copy was downloaded several years ago from another site that I cannot remember and I spent hours de-skewing the pages, fixing the darkness at the fold lines, removing graffiti. etc. Unfortunately I could not do anything about the original poor quality of some pages.

I have, as always now, added a ww2aircraft watermark to stop unscrupulous scum selling it from their websites.

 

[Shortround6]

Thank you for the rest of the members of this Forum,
I have two copies in my library but it is a very good quick overview with both the advantages and disadvantages of various setups compared and done without much bias showing through. (I am not saying none

 

[Zipper730]

You know it would be interesting if we could set up a project to essentially take what is written here and update it for modern era: After all WWII ended 72 years ago, and no classification existed that did then.

This would mean that all the various engine questions could be largely routed to one PDF file...

 

[pbehn]

You know it would be interesting if we could set up a project to essentially take what is written here and update it for modern era: After all WWII ended 72 years ago, and no classification existed that did then.

This would mean that all the various engine questions could be largely routed to one PDF file...

A great idea Zipper, I believe you are the person to lead such a project, condensing all the knowledge of all that has been learned from September 1939 to present day in a single PDF file, don't make it too long though I get bored with details.

 

[Zipper730]

That's not what I said: What I said was basically dealing with the PDF article mentioned, particularly that related to the design of piston engines.

I wouldn't mind doing some of the writing, but I'd be rather foolish to not consult certain members such as...

• drgondog: I think he's actually an aerospace engineer, so his knowledge would be invaluable
• wuzak: He has a wealth of information on piston engine designs, as well as early jet-engines
• tomo-pauk: He also has a wealth of information on aircraft and engines

As well as a number of others

While I might ask lots of questions that might annoy people I know that I have a limited base of knowledge, and that's why I ask people...

 

[pbehn]

That's not what I said: What I said was basically dealing with the PDF article mentioned, particularly that related to the design of piston engines.

I wouldn't mind doing some of the writing, but I'd be rather foolish to not consult certain members such as...

• drgondog: I think he's actually an aerospace engineer, so his knowledge would be invaluable
• wuzak: He has a wealth of information on piston engine designs, as well as early jet-engines
• tomo-pauk: He also has a wealth of information on aircraft and engines

As well as a number of others

While I might ask lots of questions that might annoy people I know that I have a limited base of knowledge, and that's why I ask people...

Zipper your fundamental problem is that you think there is always an easy answer and a short cut, the people you mention and others like Biff are already posting potted and very simplified explanations which can be understood by people with a good background knowledge. If they were discussing with people on their own level you would not understand more than the basics of the discussion.

I have a good knowledge of basic maths and physics, I can follow the basis of Hookers calculations on the Merlin supercharger, that doesn't mean I know in any way what he knew it means I know in principle what he did. That was in 1938/40 and things have become a whole lot more complicated since then

 

[Shortround6]

Unfortunately it may be too late for such a project no matter who did it. A lot of records that may have been classified during WW II have turned into land fill in the 1980s to today.
For instance Fairchild bought out Republic in 1965 and at some point in the 1980s they dumped all the old Republic paper records.

A lot of the knowledge/facts may exist someplace but not in the company records of the companies that did the original work.
Some of it is lost forever.
We know general principals but some of the fine details are already lost.
Many books were written by or about some of the principles involved but they were written for a general audience and not rivet counters.
Sir Stanley Hooker's autobiography for example is a story of his life and his interactions with other people in the Rolls Royce company and other aerospace companies. NOT a step by step account of the merlin engine or it's superchargers. In fact he was only working on the Merin and it's superchargers for a relatively short time in a career that went over 30 years.

 

[Zipper730]

Zipper your fundamental problem is that you think there is always an easy answer and a short cut

No, but I do try and explain complicated things in ways that can be easily understood if I can.

The PDF file shown did this very well, and I just wanted to funnel accurate data from WWII aviation that is no longer classified into a similar file that is more comprehensive.

the people you mention and others like Biff are already posting potted and very simplified explanations which can be understood by people with a good background knowledge.

Of course

If they were discussing with people on their own level you would not understand more than the basics of the discussion.

Of course, but that PDF wasn't based on that.

Unfortunately it may be too late for such a project no matter who did it. A lot of records that may have been classified during WW II have turned into land fill in the 1980s to today.

That could be a problem, but there is a lot of information just on this site and World War II Aviation Performance.

For instance Fairchild bought out Republic in 1965 and at some point in the 1980s they dumped all the old Republic paper records.

A lot of the knowledge/facts may exist someplace but not in the company records of the companies that did the original work.

You'd be surprised how many things were found in obscure places actually. Regardless, the idea would be to summarize piston engine design concepts from WWII era, their rationale, and make it easily understandable like how that document did.

The difference is that it would be unburdened by secrecy law that applied then, but not now; it also would correct certain errors mentioned.

Some of it is lost forever.

Regrettably, yes...

Many books were written by or about some of the principles involved but they were written for a general audience and not rivet counters.

True, but a nice .pdf would be good for a site that has lots of FAQ's

 

[MIflyer]

Thanks very much! Here is a related item.

Also here is a link to a 1941 NACA Report on two stage supercharging:
NASA Technical Reports Server (NTRS) 19930081628: Two-stage Supercharging : NASA Technical Reports Server (NTRS) : Free Download & Streaming : Internet Archive

 

[MIflyer]

Take a look at this - and note who wrote it:

https://ia801607.us.archive.org/13/items/in.ernet.dli.2015.205346/2015.205346.Aircraft-Power.pdf

 

[Shortround6]

I have a hard bound copy in my library. It is a very good overview of a lot of "basic" principles, without getting into specifics (Published in 1943 they sure weren't going to give away anything considered secret ).

It also shows the the near impossibility of trying to condense ALL the knowledge about aircraft engines during and after the war into one PDF.

This book around 450 pages and is self described as " The aim of the book is to present fundamental terms and concepts that will give the reader a good background of information on all phases of the subject. In most cases, there are a considerable number of books or technical papers in the literature that treat particular items much more thoroughly.".

I would also note that since the book is intended for college engineering seniors the author states "it is assumed that the reader is familiar with college physics, thermodynamics and fluid mechanics."

I would say that I am not familiar (in a college sense) with any of those subjects and while a some of the pages/formulas are over my head a lot can be learned by anybody from this book.

I have purchased a few other books on engine principles and/or engine design on E bay and this book is by far my favorite as it shows a lot about a wide variety of subjects without getting too bogged down. I have quoted from it or used examples from it many times in this forum.

 

[tomo pauk]

If I may, there are also several other books that people might find interesting.
By A.W. Judge: Elementary handbook of aircraft engines
Aircraft engines
By Robert Schlaifer and S.D. Heron: 'Development of aircraft engines' and 'Development of aviation fuels'

Hathi thrust dowload tool, for those that cannot wait: link

 

[MIflyer]

I still recommend the first book I ever read on the subject, "A History of Aircraft Piston Engines" by Herschel Smith. In addition to well written descriptions he also includes summary pages with HP, Bore, Stroke, Displacement, Weight, etc.

 

[HarryMann]

And of course the arch instigator (and more) of the push to develop sleeve valve engines.. Harry Ricardo. Several books available from The Ricardo Company Archives, Shoreham.

 

[Zipper730]

I have a hard bound copy in my library. It is a very good overview of a lot of "basic" principles, without getting into specifics (Published in 1943 they sure weren't going to give away anything considered secret ).

It also shows the the near impossibility of trying to condense ALL the knowledge about aircraft engines during and after the war into one PDF.

Doesn't have to be all of it, just what is mentioned in the original file right? I figure that's around 84 pages, so even if it went to 105 it'd be quite okay.

 

[pbehn]

Doesn't have to be all of it, just what is mentioned in the original file right? I figure that's around 84 pages, so even if it went to 105 it'd be quite okay.

It is an idea, but who would be the final editor/arbiter. Just look at the still live discussions about best turning performance between Spitfire and Bf 109.

 

[Shortround6]

Doesn't have to be all of it, just what is mentioned in the original file right? I figure that's around 84 pages, so even if it went to 105 it'd be quite okay.

Well, try cutting the 450 page book to 100-110 pages.
What do you want to leave out?
The chapter on intakes? or the chapter on engine mounts/installations?
Even a simple explanation of intercoolers takes 5-8 pages. and with a lot more words per page than that pamphlet/booklet uses.
BTW the booklet measures 8 1/4 in high and 5 1/4 inches wide.
I do like it as it presents a number of the advantages and disadvantages but it does so in very simply manner that makes it hard to compare engines that differ in a number of respects.

 

[pbehn]

Well, try cutting the 450 page book to 100-110 pages.
What do you want to leave out?
The chapter on intakes? or the chapter on engine mounts/installations?
Even a simple explanation of intercoolers takes 5-8 pages. and with a lot more words per page than that pamphlet/booklet uses.
BTW the booklet measures 8 1/4 in high and 5 1/4 inches wide.
I do like it as it presents a number of the advantages and disadvantages but it does so in very simply manner that makes it hard to compare engines that differ in a number of respects.

I would leave out the vowels, my wife would leave out the consonants.

 

[Zipper730]

Well, try cutting the 450 page book to 100-110 pages.

The original attachment was 84 pages...

What do you want to leave out?

84-105 pages is an increase...

I see your point though, that it won't answer all questions: That would require more research, but at least it'd cover some FAQ's

 

[MiTasol]

If I may, there are also several other books that people might find interesting.
By A.W. Judge: Elementary handbook of aircraft engines, Aircraft engines
By Robert Schlaifer and S.D. Heron: 'Development of aircraft engines' and 'Development of aviation fuels'
Hathi thrust download tool, for those that cannot wait: link

Thanks Tomo, both for the additional reading and more particularly for the Hathi Trust Download Tool.

And thank you to all the others who have made this thread cover not just the basic theories but also, for some of the many sub-topics, have expanded the basics into more detail.

Mi