A detailed analysis and comparison of the Spitfire Mk I’s and Bf 109 E’s flight performance utilizing computer simulations. (1 Viewer)

[Holtzauge]

Without exaggeration, there are probably hundreds of books that already diligently detail the history of the Spitfire Mk I and the Bf 109 E during the Battle of Britain time period. So isn't this just adding another one to the pile?

Well no, because this book is rather different: And while other books may faithfully cover the origins, the development, the different versions, the operational usage and the pilots who flew them, when it comes to these aircraft's performance the results are usually rather meagre.

And detailed performance analysis is what's new and what this book brings to the table: Because it's the first to compare these two iconic fighter utilizing verified and validated computer simulations to gauge how they truly compared, and not just repeating the same old performance numbers that have already been quoted, copied and pasted in between so many other books.

In addition, the entire performance envelope is investigated: So not just speed and climb, but also acceleration, sustained and instantaneous turn, dive, and dive and zoom performance. And this analysis has actually uncovered some previously hidden aspects of these aircraft: Not in the least concerning their turn performance, which is an area that has previously been considered to be a no contest win for the Spitfire. But as the simulations show, there are exceptions to this rule, especially if the Bf 109 drops some flap. And while the Spitfire certainly was the better turning aircraft overall, the difference was in some cases not as large as common knowledge would have us believe.

The book also covers some hypothetical scenarios: What would be the effect of reducing the Spitfire Mk I's big wing to one that instead was about the same size as on the Bf 109? Would this have made the Spitfire better or worse? Then looking at the Bf 109 E: If it instead of its low pressure aluminium radiator is equipped with a high pressure radiator cooling system like the one on the Spitfire, how much better performance would that have given it?

In summary, this book digs deeper into these aircraft's flight performance than any previous book has ever done, introducing for example acceleration, energy retention, sustained and instantaneous turn comparisons, dive, dive and zoom comparisons all in an attempt to determine just how close or far apart or close together they were regarding each particular performance aspect. In addition, the issue of the Bf 109 E's range is also analysed in greater detail than is usual in many other books, revealing that it may not have been quite as limited as it's often made out to be. And last, but not least, in the summary and conclusions, looks into if an overall winner can be crowned.

Added to this, the book also covers background information regarding the state-of-the-art at the time in aeronautics, aircraft procurement, specifications, aerodynamics, wing design, engine and propeller technology, radiator design, armament, production costs and more.

The book is 405 pages long, and contains circa 140 figures, chart and diagrams and about 100 pictures, and is available as a paperback on Amazon:

WW2 Fighter Performance volume 1: Design, Aerodynamics and Flight Performance for the Spitfire Mk I & Bf 109 E, Battle of Britain Era, by Anders F Jonsson, ISBN 978-91-987748-1-8.

Note that this link is to Amazon.com, but that the book is also available at (Amazon.co.uk, .de, .fr, .es, .it, .nl, .pl, .se, .be, .ie, .jp, .ca, .au)

More information about the book and a thumbnail collection of its complete contents can be found on author's website here:

WW2 Aircraft – Military Aircraft Performance

 

[bada]

Planned in the book- budget for next month.
I know you for years (like 20?!? ) through the il-2 forums, and know how you work.
Will be glad to read your book (and analyse all the graphs, love that stuff )
Next one Fw-190 vs spit9 ???


This month the book budget went for the JG-2 Volume4 (last piece in stock, was little bit more pricy than other volumes) by Eric Mombeek. sorry...

 

[Holtzauge]

Planned in the book- budget for next month.
I know you for years (like 20?!? ) through the il-2 forums, and know how you work.
Will be glad to read your book (and analyse all the graphs, love that stuff )
Next one Fw-190 vs spit9 ???


This month the book budget went for the JG-2 Volume4 (last piece in stock, was little bit more pricy than other volumes) by Eric Mombeek. sorry...

Thank you for those kind words and I hope you will like it! And don't hesitate to contact me here or via the contact form on my homepage if you have any questions about the contents once you've had a chance to read a bit in it.

About the next installment: As it is now I'm treating myself to a vacation: I spent all of two months being my own editor working on the book's general layout and disposition, and to try to minimize spelling errors and bad grammar so I need a break for now.

Then about being my own editor: I actually made an active choice to self-publish: Following my first book, I've had offers from legacy publishers about this book, but TBH, none of them have been able to convince me that legacy publishing is the way to go these days, so unless I get some new better offer, I will continue on this road and try to get traction on my own.

Then about the next title: I was actually leaning more towards P-51 versus Fw 190/Ta 152 in the Battle of the Reich era, but if I get good arguments to go in another direction, I'm willing to listen to those.

 

[bada]

I won't hesitate to contact, know where to find you...(stalker's laugh )
You're totally right about taking a break, nothing like some nice free time to clear your mind and get fresh ideas.

I'm actually very intrigued by the amazon print quality, this is gonna be the first KDP book in my collection, so i'll be able to see the result by myself (as i also have a long term book project i'm working on).
After having checked the average %pay per book sold using a legacy publisher, men get someting like 1.5/2€ max for such a book, this is peanuts, as this is a very niche domain, you're not gonna sell hundreds thousends of them, at least with KDP you got like 6/7€ and with few sales you can cover your ISBN nbr purchase, your "writer" test prints, etc... and you can put some bread on the table. If amazon can provide a good print quality, then the legacy publishers have a serious competitor.

If you do the battle of the reich, yes, Poney-D vs D-9 should be the way to go.(i wouldn't go with the ta152, or maybe just as a third data set to compare, but not in details. Too few of them beeing build, too few missions done.)

 

[Holtzauge]

I won't hesitate to contact, know where to find you...(stalker's laugh )
You're totally right about taking a break, nothing like some nice free time to clear your mind and get fresh ideas.

I'm actually very intrigued by the amazon print quality, this is gonna be the first KDP book in my collection, so i'll be able to see the result by myself (as i also have a long term book project i'm working on).
After having checked the average %pay per book sold using a legacy publisher, men get someting like 1.5/2€ max for such a book, this is peanuts, as this is a very niche domain, you're not gonna sell hundreds thousends of them, at least with KDP you got like 6/7€ and with few sales you can cover your ISBN nbr purchase, your "writer" test prints, etc... and you can put some bread on the table. If amazon can provide a good print quality, then the legacy publishers have a serious competitor.

If you do the battle of the reich, yes, Poney-D vs D-9 should be the way to go.(i wouldn't go with the ta152, or maybe just as a third data set to compare, but not in details. Too few of them beeing build, too few missions done.)

My experience with Kindle so far has been good: Both when it comes to clearing new editions for publishing and handling problems.

However, what you need to keep in mind when going via Kindle is that the book is printed close to the customer. This means different printers, and potentially differences in print and paper quality.

As an example, one US copy had what I would call poor paper quality and the print was more grayish than black. However, Kindle immediately refunded that book and promised to get in touch with the printer. Books printed in Germany (the only ones I've seen myself so far) have been quite good: White good quality paper and crisp clear black printing.

Covers have been very good and in line with paperback books I've received from Cambridge University Press for high end technical books. Speaking of CUP and paper and print quality, my Kindle book from Germany actually had better paper quality and the print was blacker.

In addition: Printing faults are not limited to Kindle: My first copy of A History of Aerodynamics by John D Anderson (terrific book BTW) had pages that fell out of it. I did get a new copy so no problem with that, but the lesson from this story is that even prestigious printers like Cambridge University Press can send out defective products.

Another customer of my WW1 book got a copy with stripes in some photos. But all these occurrences seem to be rare, and so far Amazon have been quick to rectify any problems and send out new copies ASAP so I can definitely recommend them over Lulu.

So, currently I see no downsides to go via Kindle and say go for it, especially if your book project is more niche like mine. Then your pool of potential customers frequent aviation forums anyway, so you can reach them there. For example, I got good traction in the Secret Projects Forum, and saw a worldwide spike in sales from posting there.

 

[bada]

Thanks for the explanation.
Searched a little bit on the web with experiences of the buyers and the writers, and it seems, like you wrote, that all depends on the place where the book is printed.
i've read some nasty stuff from usa, about one of the Printers, where the quality was worse than an home inkjet printer.
Are you sure yours was printed in germany? i've read that all "european" books were now printed in Poland. there were dicsussions there from a year or 2 ago , so maybe that changed meanwhile.. anyway if the print is good, who cares where it's pritned

 

[Daggerr]

Are you sure yours was printed in germany? i've read that all "european" books were now printed in Poland. there were dicsussions there from a year or 2 ago , so maybe that changed meanwhile.. anyway if the print is good, who cares where it's pritned

I ordered my copy via amazon.nl on November 13. On the back of the very last page it states that it is: Printed in France by Amazon, Brétigny-sur-Orge, FR.
No complaint about the paper or print quality, but as usual with POD the photos are not very sharp.

Bill Sweetman's "Trillion Dollar Trainwreck" book that I ordered via amazon.nl some time ago was also printed at that same location.

 

[Holtzauge]

The copies of my books I ordered to re-distribute myself (both the WW1 Aircraft Performance book and the new one covering the Spitfire Mk I and Bf 109 E) have been ordered from Germany. However, they are not as B bada observed printed there, but in Poland.

However, those printed in Poland I have seen so far have had both good quality paper and crisp black print. In fact, both the paper quality and "blackness" of the print have been better than paperback books published by "ordinary" and established publishers.

As an example, when I compare my copy of The Shattered Sword by Parshall and Tully from Potomac Books, the paper in the copies of my books from Wroclaw in Poland have been printed on whiter paper and with better contrast than in that book.

However, as Daggerr says, POD for some reason does not mirror the quality of the photographs provided in the original. But for sure: Some of my photos in the book are of poor WW2 era quality in the original, but even those like for example the one of Boyd on page 10 in my book which in the pdf I provided to the printers is crystal clear and with 600 dpi or more, comes out as somewhat bland in the book's print. That being said however, I can't say I'm very impressed by the quality of the photos in Potomac Book's The Shattered Sword either, so I would not be so quick to judge Kindle POD printing.

And again, I did get a proof copy of my latest book from Kindle which was of poor print quality (printed in the US) and which did not meet my standards, and when I contacted Amazon about this Kindle responded immediately and refunded it. So if anything, my experience so far of publishing via them has been positive.

 

[bada]

Thanks both for your return of experience.
So, the KDP printing is like a lottery depending of where you order from.
Good to know the com with amazon is good if something goes wrong.

 

[Holtzauge]

Thanks both for your return of experience.
So, the KDP printing is like a lottery depending of where you order from.
Good to know the com with amazon is good if something goes wrong.

But it's not just KDP: Print on demand (POD) in general is a lottery if you want to look at it that way:

Remember the examples of books from both Cambridge University Press and Potomac Books I gave you above.

POD is what the name implies: They print a copy when you order it. But even if you buy the same book, the actual printer you get it from can be different even if you buy it from the same seller.

However, what I can vouch for, is that the POD books I have bough via Amazon and been dissatisfied with (be they KDP or from other publishers like Cambridge University Press) have all been refunded or replaced at no charge.

 

[Holtzauge]

Some new information for those of you who have bought the book:

While still under investigation, I think the climb time chart on page 225 in the book may be a bit on the optimistic side for the Spitfire:

The reason for this is that it seems like the Merlin III had a 5 min limit for operation at 3000 rpms during the Battle of Britain time period, which means that the Spitfire's climb after this time has been reached would have been done at 2600 rpm instead.

More details about this and a revised climb time chart can be found on my homepage here.

 

[Daggerr]

I ordered my copy via amazon.nl on November 13. On the back of the very last page it states that it is: Printed in France by Amazon, Brétigny-sur-Orge, FR.
No complaint about the paper or print quality, but as usual with POD the photos are not very sharp.

Bill Sweetman's "Trillion Dollar Trainwreck" book that I ordered via amazon.nl some time ago was also printed at that same location.

Since then I ordered via amazon.nl the 'Aviatik 01' bookazine (by Uwe Jack) which was also a POD printed by Amazon in France at Brétigny-sur-Orge.
It has some colour images and moreover is A4 size, so apparently that is also possible.

Personally I prefer A4 sized books as they are larger and thinner and therefore easier stay opened than a 15x23 cm book of 400 pages.
Maybe something to consider for Volume 2.

 

[Holtzauge]

Since then I ordered via amazon.nl the 'Aviatik 01' bookazine (by Uwe Jack) which was also a POD printed by Amazon in France at Brétigny-sur-Orge.
It has some colour images and moreover is A4 size, so apparently that is also possible.

Personally I prefer A4 sized books as they are larger and thinner and therefore easier stay opened than a 15x23 cm book of 400 pages.
Maybe something to consider for Volume 2.

For sure, an A4 sized book would be good in that way. But with size its always a compromise, and there is also the aspect of portability and what fits into people's shelves. I personally like the US trade format since I can easily lug a book I'm reading around with me in my backpack, but I see your point, and each format of course has its own advantages.

 

[Holtzauge]

I'm currently working on a video comparing the Spitfire Mk I and Bf 109 E-4 when it comes to turn performance, and which I will post on YouTube when it's finished.

By necessity, it will of course only cover parts of what you will find in my book. And you can read more about the subject there.

But in the meantime, here are a few slides from the video to give you an idea about what it will cover.

Note that the British are missing something here: They thought they were extracting the Bf 109 E's best turn potential just at the point when the slats were opening in these trials.

So in summary, these trials are pretty much useless for comparing the Spitfire's and Bf 109's turn performance. And yet you will se these trials referenced in much litterature.

Now compare that to what Steinhoff is saying: Real manoevering only begins when the slats have come out fully, and which is also assumed as the limiting factor in the two slides below.

An interesting thing to note here, is that the Bf 109 E can actually out-turn the Spitfire Mk I at lower altitudes by dropping flaps, which I found somewhat unexpected.

 

[RCAFson]

Some new information for those of you who have bought the book:

While still under investigation, I think the climb time chart on page 225 in the book may be a bit on the optimistic side for the Spitfire:

The reason for this is that it seems like the Merlin III had a 5 min limit for operation at 3000 rpms during the Battle of Britain time period, which means that the Spitfire's climb after this time has been reached would have been done at 2600 rpm instead.

More details about this and a revised climb time chart can be found on my homepage here.

It was up to the pilot to decide when to reduce RPM and boost since there was no clockwork mechanism that would alter the throttle settings. There are accounts of pilots running a Merlin III at full boost and full revs for ~30 minutes at a time.

 

[Holtzauge]

It was up to the pilot to decide when to reduce RPM and boost since there was no clockwork mechanism that would alter the throttle settings. There are accounts of pilots running a Merlin III at full boost and full revs for ~30 minutes at a time.

Yes, pilots undoubtedly flew at longer times than recommended at higher than allowed boost settings.

I just found it interesting that there according to the Pilot's Notes for the Spitfire (that was valid during the Battle of Britain time period) seems to have been a 5 minute limit to 3000 rpms.

On a tangent, I believe that the Bf 109 at the time had a 1 minute limitation to a bit over 1.4 ata boost and it's not unlikely that some pilots broke that rule as well.

But what really surprised me was that the Bf 109 E seems to have been able to out-turn the Spitfire Mk I at lower altitudes by dropping flaps.

Frankly, I never expected that until I saw the simulation results myself.

 

[RCAFson]

Yes, pilots undoubtedly flew at longer times than recommended at higher than allowed boost settings.

I just found it interesting that there according to the Pilot's Notes for the Spitfire (that was valid during the Battle of Britain time period) seems to have been a 5 minute limit to 3000 rpms.

On a tangent, I believe that the Bf 109 at the time had a 1 minute limitation to a bit over 1.4 ata boost and it's not unlikely that some pilots broke that rule as well.

But what really surprised me was that the Bf 109 E seems to have been able to out-turn the Spitfire Mk I at lower altitudes by dropping flaps.

Frankly, I never expected that until I saw the simulation results myself.

The 5min limit is in almost all Merlin engined aircraft's Pilot's Notes but it's really just an advisory to report it upon landing. IIRC the BF109 1min limit had a mechanism to regulate it.

I suppose in theory a 109E could use the flaps to outturn a Spitfire or Hurricane, or at least try to do so, but then the 109 has bled off all it's speed and they're going low and slow over the UK and that's not a scenario that most 109E pilots would actually want to do. Also 87 octane was never used by Fighter Command during the BofB or afterwards. Even in France 100 octane seems to have been universal.

 

[Holtzauge]

The 5min limit is in almost all Merlin engined aircraft's Pilot's Notes but it's really just an advisory to report it upon landing. IIRC the BF109 1min limit had a mechanism to regulate it.

Well Pilot's Notes typically have all manner of limitations: There are limit set for at what speed you can extend the landing gear, at what speed you can extend flaps, never to exceed speeds in dives etc. But these limits are of course set by engineering limitations, and for sure, the pilot can interpret these as advisory and exceed them. And many probably did. And many probably lived to tell the tale. But there are also probably Spitfires resting at the bottom of the English Channel because of exceeding such limits.

Interesting about the 1 min limit being mechanically controlled on the Bf 109. Did not know about that. Up until now I have believed that the pilot had to control this manually. Can you please provide a reference?

I suppose in theory a 109E could use the flaps to outturn a Spitfire or Hurricane, or at least try to do so, but then the 109 has bled off all it's speed and they're going low and slow over the UK and that's not a scenario that most 109E pilots would actually want to do. Also 87 octane was never used by Fighter Command during the BofB or afterwards. Even in France 100 octane seems to have been universal.

Absolutely: And flying low and slow was probably not what most Luftwaffe pilots did either, but rather used them more for dive and zoom attacks. However, the German ace Hans-Joachim Marseille is said to have used flaps to out-turn Allied aircraft in North Africa. And another example would be USAAF ace John Godfrey, who used the flaps on his P-51B when turning against a Fw 190 D-9. So it did happen.

And even on 100 octane and +12 boost, the Spitfire Mk I will still have a greater turn radius than the Bf 109 E at lower altitudes.

 

[RCAFson]

Well Pilot's Notes typically have all manner of limitations: There are limit set for at what speed you can extend the landing gear, at what speed you can extend flaps, never to exceed speeds in dives etc. But these limits are of course set by engineering limitations, and for sure, the pilot can interpret these as advisory and exceed them. And many probably did. And many probably lived to tell the tale. But there are also probably Spitfires resting at the bottom of the English Channel because of exceeding such limits.

Interesting about the 1 min limit being mechanically controlled on the Bf 109. Did not know about that. Up until now I have believed that the pilot had to control this manually. Can you please provide a reference?



Absolutely: And flying low and slow was probably not what most Luftwaffe pilots did either, but rather used them more for dive and zoom attacks. However, the German ace Hans-Joachim Marseille is said to have used flaps to out-turn Allied aircraft in North Africa. And another example would be USAAF ace John Godfrey, who used the flaps on his P-51B when turning against a Fw 190 D-9. So it did happen.

And even on 100 octane and +12 boost, the Spitfire Mk I will still have a greater turn radius than the Bf 109 E at lower altitudes.

It's been awhile since I looked into the 1min limit on the 109 so I was hoping that you could confirm that. The 5min limit for 12lb boost was allowed after ~50 hours of testing on a Merlin III of which 8.5 hours was flown at 12lb boost:

Wayback Machine

 

[Holtzauge]

It's been awhile since I looked into the 1min limit on the 109 so I was hoping that you could confirm that.

Wayback Machine

No, AFAIK they had to keep track of this themselves in combat: On later Bf 109's you can sometimes see a "3", a "30" and "Daur" hand painted next to the rpm dial, meaning that there was a 3, a 30 minute, and a max continuous rating.

The 5min limit for 12lb boost was allowed after ~50 hours of testing on a Merlin III of which 8.5 hours was flown at 12lb boost:

Wayback Machine

Well that the engines could take much more than the limit in the manual is only natural: Both the engine manufacturer and the Air Force's acceptance agency has a horse in this race since neither wants engines to fail in qualification testing: The former to retain their reputation as a maker of reliable engines, and the latter to make sure that the AF's equipment is up to snuff.

IIRC then this was a subject of contention on the later Bf 109 K-4: Testing showed it could handle 1.98 ata, but Daimler Benz held off on signing off on that as long as they could to protect their reputation, rather than give Luftwaffe pilots what they desperately needed to stay competitive with +25 boosted Merlins.

This is all a bit like when it comes to structures: If the AF manual says you can load it to 6 g's, the pass requirement is often 9, and the engineers then add their own margin to avoid being embarrassed in testing so the aircraft ends up failing a 12 g's. Classic gold plating engineering.