Horizontal Stabilizer

Thing is, with proper combination of RPM & supercharger pressure, when keeping them into proper (real) parameters, eg between 1.15ata/1800RPM and 1.35ata/2400RPM if I remember well, for cruising, you don't have this pitch up tendency.

At 1.15ata / 1800RPM, I usually maintain a trim between 0 and 1 to have the bird flying level. I'm not fighting against the plane at all. Same when cruising at 1.35/2400.

 

Manual prop pitch is the key to learn the proper flying parameters, you have far more control (auto pitch lags behind every change of RPM or speed and perhaps has a tendency of pushing too much RPM while adapting to a new regime and perhaps, I'm just guessing here, that's what creates pitch up for some people. That or people are always using too much power out of their engine).

 

EDIT : gotta go make again a test for this as I've not flown the 109 for quite a while, too much into choppers lately. Maybe I'm rose tinted optimistic about the trim value :) But I'm sure I don't fight the plane all the time, and with the latest changes form a few weeks back, I had to push trim back quite a bit to avoid going down, I need to confirm my "between 0 & 1 trim" statement, though

Edited October 22, 2016 by Whisper

Well,

 

been testing the latest beta version 1.5, and the 109.

 

[...]Even DCS became stagnated, and I eventually gave away all of my modules.

 

?

?

 

Ah, that's from two moments in JCOMM's time, which is even more intricate than string-based time.... I wrote the first post before deciding, a few hours latter, to re-install DCS and give it a new try...

 

I was willing to find out how it felt a few versions after I left it...

 

Overall I'm glad I did it, and even spent some time yesterday at a couple of ww2 ervers.

 

Then, DCS has this great change of borrowing and lending license keys. I actually have bought the ww2 modules twice, and so I could still reinstall the three, but regarding the helicopters, the l39, a10c and f86, I can still ask them back for a while from the friend presently using those licenses - a feature which to my knowledge is unique to this sim and I find superb!

 

So, back to WW2 in DCS addiction. I never played modern combat with the jet's - too complex for me...and for that level of complexity I really prefer to play other games like simulating the operations of a Boeing 747-400 in my Aerowinx PSX :-)

Really interesting, i have read a lot of original german documents to investigate this and i never read a instruction for full forward trim with the problem nose pitching up, but i saw some real life pictures from a BF 109 with bricks in his tail for extra weight.

Can you show me this German documents pleas?

I don't have it located right now. Please use forum search, something related to high speed dive test (English translated), also stick force charts, and look for old trim/stabilizer threads (many of them) and you're plenty of read. Kürfurst web also should be hosting those charts and dive test.

 

 

S!

Is this the high speed dive test document referenced?

 

http://forum.il2sturmovik.com/index.php?app=core&module=attach&section=attach&attach_id=21158

 

(Versuchs-Bericht Nr. 109 05 E 43 'Hochgeschwindigkeitsversuche mit Me 109' dated 1943-04-15, with English translation included in the above link)

Is this the high speed dive test document referenced?

 

http://forum.il2sturmovik.com/index.php?app=core&module=attach&section=attach&attach_id=21158

 

(Versuchs-Bericht Nr. 109 05 E 43 'Hochgeschwindigkeitsversuche mit Me 109' dated 1943-04-15, with English translation included in the above link)

Affirmative, thanks :thumbup:.

 

 

S!

Is this the high speed dive test document referenced?

 

http://forum.il2sturmovik.com/index.php?app=core&module=attach&section=attach&attach_id=21158

 

(Versuchs-Bericht Nr. 109 05 E 43 'Hochgeschwindigkeitsversuche mit Me 109' dated 1943-04-15, with English translation included in the above link)

 

Thank you for posting this :thumbup:

 

I have read the document in German and English, its not the best Translation. But i tell you what this means.

 

In sheet 8:

 

Translation by Peter Pisulla:

 

Mit einer Bahnneigung von 45° wurde aus 8,5 km Höhe über NN eine Fahrt von 730km/h in 4 km Höhe erreicht. Die Flossenstellung von +1,0 (Reiseflug) musste während des Sturzes um 0,5 kopflastig getrimmt werde, da sonst die Handkraft am Knüppel nicht ausreicht, obige Fahrt zu halten.

 

"With a dive angle of 45° from

insufficient to hold this Speed."

---

The part... "because without this the pilot's strength is

insufficient to hold this Speed" can be misinterpreted and means.

 

My Translation: "because... the force by Hand at the stick, was enough to hold the Speed"

is a more a accurate Translation.

---

The meaning of all this is,

At a Speed of 730kph with a Trim of 1.5 nose heavy the Pilot was not Abel to move the stick. ( also explained in sheet 3 )

We know the BF 109 reached a max Speed of 900kph during dive tests. Max nose heavy trim is 2.0 and we know the stick was not movable with a nose heavy trim of 1.5 at 730kph, means... the only way to reach a Speed of 900kph was by turning the Trim wheel to 2.0 nose heavy. The only way to recover the plane from the dive was to turn the trim wheel back tail heavy.

 

 

The DCS bf109 is pitching up at a Speed of 500kph with a 2.0 nose heavy trim, to do a high Speed dive you have to push the stick Forward.

 

 

Can you guys see the error?

 

 

Edited October 23, 2016 by Jafferson

- snip -

Jafferson, please read my previous post.

 

See also jcomm's comment about his conversation with Klaus Plasa, current pilot on the 109.

 

And if that's not enough, here is a small thread of 41 pages that you can digest:

https://forums.eagle.ru/showthread.php?t=135453

 

There are others.

 

Please just let it go.

And if that's not enough, here is a small thread of 41 pages that you can digest:

https://forums.eagle.ru/showthread.php?t=135453

 

There are others.

Can you guys see the error?

The error is you are late and missed the previous hundred threads about the subject. You can try translating again what you want it to be. Charts say what they say, in that same reading and others, you translate it like that or not, still the chart is there.

 

 

Let me point out just one thing, for your known, and may be you understand better the whole paper after that,

The DCS bf109 is pitching up at a Speed of 500kph with a 2.0 nose heavy trim, to do a high Speed dive you have to push the stick Forward.

DCS don't have a 2.0º trim setting, look closer and you'll see number 2 isn't reached. DCS feature a 1.15º trim like the paper says. And an extra detail, 500Km/H in the paper is always TAS, not your IAS reading.

 

 

Please, read the previous threads before jumping again on the same.

 

 

S!

Jafferson, please read my previous post.

 

See also jcomm's comment about his conversation with Klaus Plasa, current pilot on the 109.

 

And if that's not enough, here is a small thread of 41 pages that you can digest:

https://forums.eagle.ru/showthread.php?t=135453

 

There are others.

 

Please just let it go.

 

I have read this post a time ago, did you saw the bricks in the tail ?

https://forums.eagle.ru/showpost.php?p=2560784&postcount=398

You cant compare a 70 years old klaus plasa bird from the Museum with a new BF109 from 1944 under war conditions. Klaus crashed his 109 several times and he never reached 900kph with his bird. And why, because his bird is falling apart by his age.

His bird have no weapons mounted...

The MK 108 have a weight of 58 kg

The MG 131 have a weight of 20,5 kg x 2

Its a total weigth of 99 kg ( without ammo ) missing in Klaus Plasas Bird,

and he have still bricks in his Tail. Nobody knows how the trim Tabs are adjusted by the ground Crew.

 

This is not comparable!

 

Ingolstadt is 160 km from my place, if i have time i drive there and talk to him.

 

Did you even read the Dive test Document?

Did you even read the Dive test Document?

Several times, did you? :huh:

 

 

You cant compare a 70 years old klaus plasa bird from the Museum with a new BF109 from 1944 under war conditions.

:doh: Rotte 7 is a Spanish built Ha1112, circa ~1956, later on re-engined with DB605. I don't have to drive, I'm sitting right now at nº88 street, she was built in the nº90 :music_whistling:. Even though Merlin powered Spanish manual of the aeroplane also stated you cannot trim beyond a certain speed. Clues are in the air :lol:.

 

 

S!

 

P.D.: 900Km/H TAS, you know what is True Air Speed versus Indicated Air Speed, do you? :noexpression:

Thank you for posting this :thumbup:

 

I have read the document in German and English, its not the best Translation. But i tell you what this means.

 

In sheet 8:

 

Translation by Peter Pisulla:

 

Mit einer Bahnneigung von 45° wurde aus 8,5 km Höhe über NN eine Fahrt von 730km/h in 4 km Höhe erreicht. Die Flossenstellung von +1,0 (Reiseflug) musste während des Sturzes um 0,5 kopflastig getrimmt werde, da sonst die Handkraft am Knüppel nicht ausreicht, obige Fahrt zu halten.

 

"With a dive angle of 45° from

8.5 km altitude over sea level a speed of IAS-Va= 730 km/h at 4 km was

reached. The trim setting of + 1.0° (cruising speed) had to be changed

0.5° more nose heavy, because without this the pilot's strength is

insufficient to hold this Speed."

---

The part... "because without this the pilot's strength is

insufficient to hold this Speed" can be misinterpreted and means.

 

My Translation: "because... the force by Hand at the stick, was enough to hold the Speed"

is a more a accurate Translation.

---

The meaning of all this is,

At a Speed of 730kph with a Trim of 1.5 nose heavy the Pilot was not Abel to move the stick. ( also explained in sheet 3 )

We know the BF 109 reached a max Speed of 900kph during dive tests. Max nose heavy trim is 2.0 and we know the stick was not movable with a nose heavy trim of 1.5 at 730kph, means... the only way to reach a Speed of 900kph was by turning the Trim wheel to 2.0 nose heavy. The only way to recover the plane from the dive was to turn the trim wheel back tail heavy.

 

 

The DCS bf109 is pitching up at a Speed of 500kph with a 2.0 nose heavy trim, to do a high Speed dive you have to push the stick Forward.

 

 

Can you guys see the error?

 

 

 

As a German native speaker, it is my understanding the pilot lacked the strength to keep the nose pushed into the dive without using +1.5 nose heavy trim.

 

At no point does the document you're citing imply the stick had been left in or near the neutral position after the dive had been initiated.

 

<snip>...da sonst die Handkraft am Knüppel nicht ausreicht, obige Fahrt zu halten.

 

<snip>...as the pilot's arm strength was insufficient to hold the above speed. (<= really rough partial translation)

 

In short, the pilot was incapable of pushing the stick away from himself far enough to hold 730 kph indicated airspeed in a dive without trimming the plane more nose heavy.

The error is you are late and missed the previous hundred threads about the subject. You can try translating again what you want it to be. Charts say what they say, in that same reading and others, you translate it like that or not, still the chart is there.

 

 

Let me point out just one thing, for your known, and may be you understand better the whole paper after that,

DCS don't have a 2.0º trim setting, look closer and you'll see number 2 isn't reached. DCS feature a 1.15º trim like the paper says. And an extra detail, 500Km/H in the paper is always TAS, not your IAS reading.

 

 

Please, read the previous threads before jumping again on the same.

 

 

S!

 

The paper Shows both, IAS, TAS and Mach (sheet 2)

Ok 2.0 was never reached, much better. So they reached a TAS of 906km/h with a Trim Setting below 2.0

Sheet 8 expains a pre trim of 1,0 it was necessary during the dive to trim more nose heavy by 0,5

So 1,0 + 0,5 = 1,5 right?

Sheet 8 explains also a trim by 1,7

 

The Translater missed a whol part of the text (während des sturzes = during the dive)

 

"muste während des sturzes um 0,5 kopflastig getrimmt werden"

means... "it was necessary during the dive to trim more nose heavy by 0,5"

So the Pilot Trimed during the dive with the Trim wheel, nothing about trim Tabs!

You know what im mean?

Edited October 24, 2016 by Jafferson

As a German native speaker, it is my understanding the pilot lacked the strength to keep the nose pushed into the dive without using +1.5 nose heavy trim.

 

At no point does the document you're citing imply the stick had been left in or near the neutral position after the dive had been initiated.

 

<snip>...da sonst die Handkraft am Knüppel nicht ausreicht, obige Fahrt zu halten.

 

<snip>...as the pilot's arm strength was insufficient to hold the above speed. (<= really rough partial translation)

 

In short, the pilot was incapable of pushing the stick away from himself far enough to hold 730 kph indicated airspeed in a dive without trimming the plane more nose heavy.

 

Thank you, simple explanation... and nice translation :thumbup:

Which means the stick has to be pushed forward + full trimmed nose heavy to force the plane into the dive. Where's the discrepancy with the sim?

Which means the stick has to be pushed forward + full trimmed nose heavy to force the plane into the dive. Where's the discrepancy with the sim?

 

My point exactly.

Which means the stick has to be pushed forward + full trimmed nose heavy to force the plane into the dive. Where's the discrepancy with the sim?

 

LOL :lol: are you kiding me? Stop Trolling!

Ok 2.0 was never reached, much better. So they reached a TAS of 906km/h with a Trim Setting below 2.0

Not at all :lol:. As a result of dive tests 1.15º limit was established, in the first test the pilot almost kill himself using a higher trim setting, that's why he recommends that limit after a second test. Really, have you read the whole paper?

 

 

"muste während des sturzes um 0,5 kopflastig getrimmt werden"

means... "it was necessary during the dive to trim more nose heavy by 0,5"

So the Pilot Trimed during the dive with the Trim wheel, nothing about trim Tabs!

You know what im mean?

Yes, I know perfectly, trim tabs and set on ground that's why they don't talk at all about them. Pilot needs to use trim because he lacks strength enough to keep controls by himself, you know what I mean? :lol: :thumbup: Even though that, the same pilot recommends 1.15º limit to prevent controls reversing at higher speeds. Really mate, have you read it?

 

 

 

LOL are you kiding me? Stop Trolling!

No mate, are you kidding us? :smilewink:

 

 

S!

I have read this post a time ago, did you saw the bricks in the tail ?

https://forums.eagle.ru/showpost.php?p=2560784&postcount=398

You cant compare a 70 years old klaus plasa bird from the Museum with a new BF109 from 1944 under war conditions. Klaus crashed his 109 several times and he never reached 900kph with his bird. And why, because his bird is falling apart by his age.

His bird have no weapons mounted...

The MK 108 have a weight of 58 kg

The MG 131 have a weight of 20,5 kg x 2

Its a total weigth of 99 kg ( without ammo ) missing in Klaus Plasas Bird,

and he have still bricks in his Tail. Nobody knows how the trim Tabs are adjusted by the ground Crew.

 

This is not comparable!

 

Ingolstadt is 160 km from my place, if i have time i drive there and talk to him.

 

Did you even read the Dive test Document?

Oh my..

 

If you had bothered reading the thread I showed you thoroughly, you would have noticed the post where Yo-Yo mentions that he has the total weight and CoG charts of that aircraft.

Besides, Klaus Plasa flies more than that Bf 109, did you know that?

 

Secondly, yes, I have read that report several times, and I don't need to read it any more, I'm tired of it honestly. :)

I got the conclusions I needed.

Besides, as mentioned before, ED uses lots of documents, not only one, and not only documents found on the intarweb.

 

Thirdly, and most important:

If you truly believe, that you alone can find something in a line of one document, that has not already been found and discussed to oblivion through a long thread (out of several) with participation of both lots of users and ED staff, among them ED's chief FM designer, and also convince ED that they must change what has already been discussed excessively on this basis, then by all means go ahead.

 

Then I can only wish you good luck. :)

Edited October 24, 2016 by Sporg

Not at all :lol:. As a result of dive tests 1.15º limit was established, in the first test the pilot almost kill himself using a higher trim setting, that's why he recommends that limit after a second test. Really, have you read the whole paper?

 

 

Yes, I know perfectly, trim tabs and set on ground that's why they don't talk at all about them. Pilot needs to use trim because he lacks strength enough to keep controls by himself, you know what I mean? :lol: :thumbup: Even though that, the same pilot recommends 1.15º limit to prevent controls reversing at higher speeds. Really mate, have you read it?

 

 

 

No mate, are you kidding us? :smilewink:

 

 

S!

 

 

+1

 

The 1.15º limit was exactly what I got out of that report too.

I believe you are not correct.

 

Never mind SiTh, someone provided me with links that reminded me about this rather old thread, and even the messages I exchanged with Klaus Plaza and seem to confirm this pitching up tendency.

OK i agre with the 1.15 Limit, its explainet in sheet 9 and 10, they enlarged the trim tab by 100% as well.

But the DCS Trim wheel locks not limited at 1.15 and the bird is still pitching nose up with a full nose heavy trim at 500kph.

The Chart Shows a neutral stick Position at 500kph, thats why im guess something is wrong.

 

All in All... since the last patch the Bird is flying much better :)

Hey guys! The graphs Yo-Yo used for balance behavior were from a NII VVS report of a Bf 109 G2/R6 (with gunpods) captured near Stalingrad and there is far as I know no 109 K-4 Ladeplan for exact CoG available at all.

 

The main problems I still have with this approach is that the data is based on a captured and force landed G-2 with gunpods and we know nothing of how the ground adjustable trim tabs were setup for the test.

 

I am still at a loss why no trim tabs for the elevator are added, as we can adjust rudder and aileron trim tabs in the options since many version ago. I find that to be very useful and have my ailerons set to -7 at all times. Even if the trim tabs in the VVS report are "assumed" neutral, then it should be viable for the pilot to trim the aircraft via the trim tabs to reduce the pitch up tendency in flight.

 

I dont have access to my flight PC at the moment, but you guys could certainly check if the elevator response at 1.15° stab setting corresponds to the graph in the high speed dive trials. I have been citing this test for some time, as I find a much lower rudder authority in DCS than described.