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

[Engineman]

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.

View attachment 874316

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.

View attachment 874317

View attachment 874318

In fact, the Bf 109 could use any amount of flap the pilot chose for manoeuvre. 0.5 Degree, 3.25 degree, 20 degree, whatever, because it was infinitely variable on a screw thread.
So, automatic manoeuvre slats with flap was a Bf 109 speciality that is not defined.
Modern in flight assessment of Bf 109 Slat operation has shown that Slat operation was not a disturbance to flightpath, it just progressively increased the Cl Max and droop ailerons on the early models had a further slow speed improvements with flap.
The Bf 109 Pilot could also select the cooling flaps closed to reduce drag for short periods in a combat.
Finally, here the Bf 109 power setting to compare with the Merlin 12lb Boost would be 1.42 ata at higher rpm as well.
Eng

 

[RCAFson]

In fact, the Bf 109 could use any amount of flap the pilot chose for manoeuvre. 0.5 Degree, 3.25 degree, 20 degree, whatever, because it was infinitely variable on a screw thread.
So, automatic manoeuvre slats with flap was a Bf 109 speciality that is not defined.
Modern in flight assessment of Bf 109 Slat operation has shown that Slat operation was not a disturbance to flightpath, it just progressively increased the Cl Max and droop ailerons on the early models had a further slow speed improvements with flap.
The Bf 109 Pilot could also select the cooling flaps closed to reduce drag for short periods in a combat.
Finally, here the Bf 109 power setting to compare with the Merlin 12lb Boost would be 1.42 ata at higher rpm as well.
Eng

What was the flap deployment speed limits?

 

[Engineman]

What was the flap deployment speed limits?

The Flap limiting speed is 250 km/h in the Handbook.

Eng

 

[Holtzauge]

A nice thing with the Bf 109 flaps was that the control wheel used to deploy them was placed together with the one controlling the tailplane incidence, right by the pilot's left hand and that when these were turned together in the same direction, this ingeniously more or less cancelled out the change in pitch trim caused by the changing the flap angle.

So in theory, a Bf 109 pilot could in a prolonged turn fight gradually turn both wheels anti-clockwise as the speed bled off and thus always have the optimal amount of flap out while at the same time compensating for the changed pitch trim. Quite a nifty system.

Of course, one can always question the wisdom of doing this, and that the Bf 109 should really be flown to its strengths, i.e. in high speed slashing attacks.

But that does not change the fact that this feature added another item to the Bf 109 pilot's toolbox, and which some pilots like Hans-Joachim Marseille actually used.

 

[Shortround6]

109s came with a variety of engines over the years. Only one (?) had the one-minute timer. There may have been nothing to prevent reactivating the timer almost immediately.

A lot of the US and British engines also had a warning note that the 5 minutes was also subject to the engine temperature staying out of the red. What they may have been able to do on cool or cold day is different than a hot summer day.

Using the flaps for turning is a two-edged sword. It gives more lift but it also creates more drag. You also only get the higher lift at higher than normal angles of attack and high angles of attack already have higher drag than "normal" flight.
A lot depends on each type of aircraft and the type of flaps and the wing. Trying to use the split flaps on a Hurricane or Spit was not going to end well. They were designed to be more of an airbrake than a way to generate lift.

 

[bada]

Forgot to put it here, but i've made a review about this book on the website.
It's in the top10 of the visited pages

 

[SaparotRob]

Just checking in. Crimea_River takes attendance.

 

[Holtzauge]

Forgot to put it here, but i've made a review about this book on the website.
It's in the top10 of the visited pages

Thanks for the heads-up B bada , I did not know that you had written a review.

Well what can I say? Now that I've read it, I have to ask you if you want the job as Marketing Manger?

Jokes aside, I'm a bit worried about the print quality in your copy though: Granted, there has been some variations, but the copies I've received have been quite good, and just as good, if not even better, than my copy of Parshall & Tully's Shattered Sword from Potomac Books. But as you say, POD books vary, and quality may vary depending on where and when they were printed.

The nice thing with Amazon KDP though (as opposed to one other POD publisher who shall remain unmentioned), is that I've had no trouble at all with their customer support: When I was reviewing drafts, they sent me a copy where the print was to weak and grayish, and another one where the spine text was not aligned, and in both cases they refunded and sent me new copies no questions asked.

Another point to their credit is that I just restocked on copies I use for signing purposes, and while these were of good print quality, they were badly packaged and arrived slightly damaged. Again, no problems with customer support, and they refunded and promised to get in touch with that particular POD supplier to ensure that it did not happen again.

So up until now, I really only have good things to say about Amazon KDP, and if I ever get around to a Volume 2, I see no reason not to go with them again.

And if you are not happy about the print quality in your copy, then contact customer support and tell them you've been in contact with me and ask them to send you a new one.

Anyway, thanks for the positive review, and glad you liked the book!

Also, if you have any questions, please don't hesitate to contact me.

Best wishes

Anders

 

[bada]

Hi Holtzauge,

By Marketing Manager, you mean leaving a review on amazon, i presume? This was the plan, but started holidays after after the Site update and didn't found the time to write it yet. Thought about making a dual language review, french/english (yes, i know, there is the auto translate option on amazon) but when people see a review not in their language, there is the tendency to skip it.

I won't send it back for 2 reasons:
1° i already tortured the book (with annotations and handling)
2° it's a perfect exemple that can be used as quality reference for the day mine will be finished, if it's ever finished...

Like i wrote in the review, i dived right into it the day i received it, didn't want to loose time with sending back, waiting for the new one, etc... the chistams kid's feeling, you see

You're welcome for the review.

 

[Holtzauge]

Well B bada , I'm glad you found it interesting enough to overlook your copy's blemishes, but the POD printers really need to get their ducks in a row I think, since the varying level of quality in their products is hardly to their credit. But for sure, even the sun has its spots, and while it's some time ago now, I had to return a Cambridge University Press book because the pages fell out of it due to a poor binding, and the print and paper in that book was certainly no better than Amazon KDP's.

About a review in Amazon: That would help, but while I've found Amazon KDP to be a good publishing partner, when it comes to reviews though, I'm not as happy: I've sold hundreds of books now (still some way to get to one thousand alas), and while I would have liked more to at least try to review it, I've had comments from people who have tried, only to be met by an auto-reply from Amazon saying that "the review does not meets Amazon's standards, or contains offensive text", and when asking what's wrong, gotten what seems to be rather unhelpful answers. For example, one had to go through three new review iterations before finally figuring out that the "Fokker" in "Fokker Dr.I" was "offensive" text, and that instead writing the Dr.I triplane got it through on the fourth try!

 

[bada]

Thanks for the tips about the review on kdp, will try not to use my usual "poetic writing"

SLightly OT, but did you have some experience with prints on demand/distributors like ingramspark, bookvault,bod, lulu, etc???

 

[Holtzauge]

Thanks for the tips about the review on kdp, will try not to use my usual "poetic writing"

SLightly OT, but did you have some experience with prints on demand/distributors like ingramspark, bookvault,bod, lulu, etc???

Apart from Amazon KDP, I have experience with Lulu as well. But that did not work out as I had hoped, and is something I'm hesitant to write about in a public forum. So send me a PM if you want details.