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Bf 109 elevator trim


grafspee

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With ground adjustable tabs we wouldn't have this conversation. ;)
What would "ground adjustable tabs" achieve, other than full trim???!!! There is no difference if you dial it in with the wheel or have it fixed to (2)...

Shagrat

 

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We need at least 3 or even 4. Because the interceptors don't fly long ranges, the logic behind low ATA cruising fails. You don't fly @ cruise speed when you want to intercept incoming enemies.

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We need at least 3 or even 4. Because the interceptors don't fly long ranges, the logic behind low ATA cruising fails. You don't fly @ cruise speed when you want to intercept incoming enemies.
That's how the 109 was built. As it is no longer in service, it is difficult to make design changes... try an AtA of 0.9 at 12.000 to 13.000 ft (4 Km) and use the trim wheel like the pilots did.

Shagrat

 

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Will do.

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Asus Z97 PRO Gamer, i7 4790K@4.6GHz, 4x8GB Kingston @2400MHz 11-13-14-32, Titan X, Creative X-Fi, 128+2x250GB SSDs, VPC T50 Throttle + G940, MFG Crosswinds, TrackIR 5 w/ pro clip, JetSeat, Win10 Pro 64-bit, Oculus Rift, 27"@1920x1080

 

Settings:

2.1.x - Textures:High Terrain:High Civ.Traffic:Off Water:High VisRan:Low Heatblur:High Shadows:High Res:1920x1080 RoC:1024 MSAA:4x AF:16x HDR:OFF DefS: ON GCI: ON DoF:Off Lens: OFF C/G:390m Trees:1500m R:max Gamma: 1.5

 

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Ok, just retested in the current Openbeta, Caucasus freeflight. Climbed to 4.200m and throttled back to 0.9 AtA. With trim tabs not set in the options menu, just using a bit of rudder and elevator trim of about 1.5 to 1.7 on the trim gauge trimmed here for cruise at 450 km/h IAS in "level" flight, as expected.

Above 0.95 AtA she speeds up and you need a constant input nose down, as the trim isn't enough anymore. Again, as expected. So nothing changed from my last flight over a year ago. :)

Shagrat

 

- Flying Sims since 1984 -:pilotfly:

Win 10 | i5 10600K@4.1GHz | 64GB | GeForce RTX 3090 - Asus VG34VQL1B  | TrackIR5 | Simshaker & Jetseat | VIRPIL CM 50 Stick & Throttle | VPC Rotor TCS Plus/Apache64 Grip | MFG Crosswind Rudder Pedals | WW Top Gun MIP | a hand made AHCP | 2x Elgato StreamDeck (Buttons galore)

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  • ED Team

It flies trimmed up to 1.1 - 1.15 ata with centered ball (by default settings). Rear tank full or empty can change things a bit.

The reason of decreasing nose-down trim range for late 109 models was because of diving trim problems - too nose-heavy trimmed plane was very hard in recovering.

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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It flies trimmed up to 1.1 - 1.15 ata with centered ball (by default settings). Rear tank full or empty can change things a bit.

The reason of decreasing nose-down trim range for late 109 models was because of diving trim problems - too nose-heavy trimmed plane was very hard in recovering.

Yep, as I said. This is how the plane works. Climb, level out at altitude, then reduce AtA to cruise performance and trim her level. Full tank in the instant action mission sure puts CoG to the back, so over time you will need to adjust a bit and gain more trim authority.

There seems nothing wrong with the trim, nor the FM.

Shagrat

 

- Flying Sims since 1984 -:pilotfly:

Win 10 | i5 10600K@4.1GHz | 64GB | GeForce RTX 3090 - Asus VG34VQL1B  | TrackIR5 | Simshaker & Jetseat | VIRPIL CM 50 Stick & Throttle | VPC Rotor TCS Plus/Apache64 Grip | MFG Crosswind Rudder Pedals | WW Top Gun MIP | a hand made AHCP | 2x Elgato StreamDeck (Buttons galore)

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The ground adjustable trim tabs are available on the special tab for the Bf-109 under main menu options, since years! :smartass:

It represents going to your maintennace tech and have him set the trim to your liking.

 

attachment.php?attachmentid=180647&stc=1&d=1520720162

 

Dont see the one for elevator trim.

I dont think is take off assistance.

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Dont see the one for elevator trim.

 

I dont think is take off assistance.

That's what the Elevator Trim Wheel is for... as I said above.

Shagrat

 

- Flying Sims since 1984 -:pilotfly:

Win 10 | i5 10600K@4.1GHz | 64GB | GeForce RTX 3090 - Asus VG34VQL1B  | TrackIR5 | Simshaker & Jetseat | VIRPIL CM 50 Stick & Throttle | VPC Rotor TCS Plus/Apache64 Grip | MFG Crosswind Rudder Pedals | WW Top Gun MIP | a hand made AHCP | 2x Elgato StreamDeck (Buttons galore)

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That's what the Elevator Trim Wheel is for... as I said above.

 

He's referring to the ground-crew adjustable elevator trim, actually available as two trim plates one on each elevator, in the real K-4, and graphically in the DCS K-4 too.

 

This would allow for better fine tuning depending on rigging, loading & CoG, etc... Like IRL...


Edited by jcomm

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He's referring to the ground-crew adjustable elevator trim, actually available as two trim plates one on each elevator, in the real K-4, and graphically in the DCS K-2 too.

 

 

 

This would allow for better fine tuning depending on rigging, loading & CoG, etc... Like IRL...

It sure allows for "callibrating" the elevator trim wheel for (0) with loadouts to achieve required trim authority. Not to mess up the design decision of the engineers to prevent pilots from trimming too much nose down, and losing planes in a dive, as Yo-Yo mentioned. But that is easy to implement, as soon as anyone provides a trustworthy source the crews/pilots did use these to mess up the flight characteristics...

The main issue is, you did cruise at 0.9 to 1.15 AtA and it's no problem to trim for level flight, if you fly the plane like your supposed to.

Shagrat

 

- Flying Sims since 1984 -:pilotfly:

Win 10 | i5 10600K@4.1GHz | 64GB | GeForce RTX 3090 - Asus VG34VQL1B  | TrackIR5 | Simshaker & Jetseat | VIRPIL CM 50 Stick & Throttle | VPC Rotor TCS Plus/Apache64 Grip | MFG Crosswind Rudder Pedals | WW Top Gun MIP | a hand made AHCP | 2x Elgato StreamDeck (Buttons galore)

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"Take off assistance" is just an aid to help keep the aircraft straight while on the ground. Once in the air, it does nothing. You need to use Rudder to keep the ball centered unless at the prescribed power and speed mentioned, then it neutralizes itself.

 

OR you could use "Auto Rudder" if you do not have rudder peddles (or equivalent control).

 

If you want to change the speed/power settings where the aircraft naturally stabilizes, you can mess around with the on ground rudder trim setting, but this is ill advised unless you really know what you are doing and why.

 

Good luck

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It sure allows for "callibrating" the elevator trim wheel for (0) with loadouts to achieve required trim authority. Not to mess up the design decision of the engineers to prevent pilots from trimming too much nose down, and losing planes in a dive, as Yo-Yo mentioned. But that is easy to implement, as soon as anyone provides a trustworthy source the crews/pilots did use these to mess up the flight characteristics...

The main issue is, you did cruise at 0.9 to 1.15 AtA and it's no problem to trim for level flight, if you fly the plane like your supposed to.

 

The trim tabs and stab angle adjustment serve completely different purposes, I hope you realize that. The trim tabs regulate the neutral aerodynamic elevator position at corresponding stabilizer setting. The stabilizer incidence adjusts basal downforce at load neutral elevator position but also elevator zero incidence as well as elevator maximum deflection angle.

 

The 109 K models (as well as G-10 & ASB/ASC engined G-14 models) had double the trim tab area compared to earlier 109 models because the elevator authority at a perticular horizontal stab setting, was limiting the nose down capacity to an unsatisfactory maximum at full motor output. (Sounds familiar?) The aerodynamic elevator zero incidence (at a stab incidence of 1,45°) was in a position where the test pilot was not able to produce the necessary force to depress into a dive angle beyond 60°. The solution was to change the aerodynamic elevator zero incidence at unchanged & safe stabilizer incidence (in respect to the pullout capability) by doubling the trim tab area. Btw they tested to Mach 0.81.

These trim tabs then were set to produce a downforce on the elevator (trim tabs physically angled upwards), so the elevator was producing lift (physically angled downward) at the tailplane. Seems confsing at first, but is the simplest of aerodynamics. In level flight this obviously also produces more lift at the tailplane and changes the elevator neutral position to a more nose down attitude.

 

Report 109 05 E 43 "Hochgeschwindigkeitsversuche mit 109" cites:

 

The limiter for the first flights was at +1,45°. The elevator forces at this setting were not sufficient to go beyond 60° dive angle at 100% motor power. For this reason elevator trim tabs double the size of the normal ones were installed.

This btw, is the very report you guys credit falsely with stating something about limiting nose down capability for safety reasons and protecting pilots. Since you are a fellow German I urge you to read it and tell me where exactly it states this! The reason for this test was named as:

Clarification of accidents within the troops (aileron overcompensation and lack of elevator authority at high Mach numbers).

The conclusion of this test was a completely different one, namely that you couldnt put enough force on the elevator in the first place to reach any dangerous dive angle above 60°.... Then double sized trim tabs were introduced which could yield elevator force reversal at high Mach numbers, so in turn the stab angle was limited to +1,15°, where elevator force reversal did not happen anymore.

 

This test resulted in a production line change of later models to double elevator trim tabs and limiting the stab angle to +1,15° / +1,10°.

I have posted bits and pieces of this information before, as well as that we have a G model elevator on our DCS K-4 and all of the trim difficulties we have stem from exactly these two problems! G model elevator on a K-4 and no trim tabs on the elevator, even though the quoted report above states the very function and importance of these trim tabs.

 

 

Please compare the trim tabs on a G-6 and K-4:

 

G-6

G-6.jpg

K-4

K-4.png

 

And the K-4 horizontal stabilizer setting + marked double trim tab area (verlängerte Bügelkante in german) 109 K-4 manual page 126

elevator-K4.jpg

 

 

Please also compare maximum elevator deflection at the corresponding horizontal stabilizer setting to other models... You will realize that K & G-10 models have a diferently geared elevator and using soviet G-2 documentation wont work for a correct K-4 elevator.

 

F

elevator-F.jpg

 

G-2

G-6-elevator.png

 

G-10 (important is the part G-10/U4 teilweise 27° up 24° down) so G-10/U4 with MK108 has the same elevator as the K-4

elevator-G-10.jpg


Edited by rel4y

Cougar, CH and Saitek PnP hall sensor kits + shift registers: https://forums.eagle.ru/showthread.php?t=220916

 

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The trim tabs and stab angle adjustment serve completely different purposes, I hope you realize that. The trim tabs regulate the neutral aerodynamic elevator position at corresponding stabilizer setting. The stabilizer incidence adjusts basal downforce at load neutral elevator position but also elevator zero incidence as well as elevator maximum deflection angle.

 

The 109 K models (as well as ASB/ASC engined G-14 models) had double the trim tab area compared to earlier 109 models because the elevator authority at a perticular horizontal stab setting, was limiting the nose down capacity to an unsatisfactory maximum. The aerodynamic elevator zero incidence (at a stab incidence of 1,45°) was in a position where the test pilot was not able to produce the necessary force to depress into a dive angle beyond 60°. The solution was to change the aerodynamic elevator zero incidence at unchanged & safe stabilizer incidence (in respect to the pullout capability) by doubling the trim tab area. Btw they tested to Mach 0.81.

These trim tabs then were set to produce a downforce on the elevator (trim tabs physically angled upwards), so the elevator was producing lift (physically angled downward) at the tailplane. Seems confsing at first, but is the simplest of aerodynamics. In level flight this obviously also produces more lift at the tailplane and changes the elevator neutral position to a more nose down attitude.

 

Report 109 05 E 43 "Hochgeschwindigkeitsversuche mit 109" cites:

 

This btw, is the very report you guys credit falsely with stating something about limiting nose down capability for safety reasons and protecting pilots. Since you are a fellow German I urge you to read it and tell me where exactly it states this! The reason for this test was named as:

The conclusion of this test was a completely different one, namely that you couldnt put enough force on the elevator in the first place to reach any dangerous dive angle above 60°.... Then double sized trim tabs were introduced which could yield elevator force reversal at high Mach numbers, so in turn the stab angle was limited to +1,15°, where elevator force reversal did not happen anymore.

 

This test resulted in a production line change of later models to double elevator trim tabs and limiting the stab angle to +1,15° / +1,10°.

Please compare the trim tabs on a G-6 and K-4:

 

G-6

G-6.jpg

K-4

 

K-4.png

 

And the K-4 horizontal stabilizer setting + marked double trim tab area (verlängerte Bügelkante in german) 109 K-4 manual page 126

 

elevator-K4.jpg

All correct, but the trim tabs were adjusted, by the engineers while calibrating the elevator (as you described), not by the pilot, or the crew to the pilots liking. Unlike the aileron and rudder trim, which were adjusted for long flights.

The discussion was about "getting trim adjustment" in the menu to trim for neutral flight beyond cruise speed. That was not the intention of the trim tabs.

BTW, what makes you think the adjustment through the elevator trim tabs is not represented in the FM?

Shagrat

 

- Flying Sims since 1984 -:pilotfly:

Win 10 | i5 10600K@4.1GHz | 64GB | GeForce RTX 3090 - Asus VG34VQL1B  | TrackIR5 | Simshaker & Jetseat | VIRPIL CM 50 Stick & Throttle | VPC Rotor TCS Plus/Apache64 Grip | MFG Crosswind Rudder Pedals | WW Top Gun MIP | a hand made AHCP | 2x Elgato StreamDeck (Buttons galore)

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BTW, what makes you think the adjustment through the elevator trim tabs is not represented in the FM?

 

Because the elevator is modeled after a standard trim tab soviet tab G-2 report. You qouted YoYos post about this yourself.

 

But contrary to when we provided him with information about the incorrect drag coefficient of the 109 due to wheel well covers, or provided the report on correct aileron forces he doesnt address elevator problematic.

 

I have calculated the K-4 elevator hinge moments based on 109 blueprint documents (https://www.ebay.de/itm/WW2-German-Flugzeug-Bauplan-Blueprints-Me109-Fw190/391441687123?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649) and with these it is possible to correct the elevator. I have provided the drag curves for the Hispano cannons to YoYo before and wouldnt mind to give him this data as well if it only gets finally corrected.

Cougar, CH and Saitek PnP hall sensor kits + shift registers: https://forums.eagle.ru/showthread.php?t=220916

 

Shapeways store for DIY flight simming equipment and repair: https://www.shapeways.com/shops/rel4y-diy-joystick-flight-simming

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  • ED Team

 

 

Please also compare maximum elevator deflection at the corresponding horizontal stabilizer setting to other models... You will realize that K & G-10 models have a diferently geared elevator and using soviet G-2 documentation wont work for a correct K-4 elevator.

 

F

elevator-F.jpg

 

G-2

G-6-elevator.png

 

G-10 (important is the part G-10/U4 teilweise 27° up 24° down) so G-10/U4 with MK108 has the same elevator as the K-4

elevator-G-10.jpg

 

The Soviet report was related to the ELEVATOR deflection, so there is no reason to consider it irrelevant.

And, regarding "different geared elevator" - I think you mean that the stick forces are different? Then, please determine the whole elevator travel for both cases. It is not different geared", it is "different bias" in the linkage.

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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The trim tabs and stab angle adjustment serve completely different purposes, I hope you realize that. The trim tabs regulate the neutral aerodynamic elevator position at corresponding stabilizer setting. The stabilizer incidence adjusts basal downforce at load neutral elevator position but also elevator zero incidence as well as elevator maximum deflection angle.

 

The 109 K models (as well as G-10 & ASB/ASC engined G-14 models) had double the trim tab area compared to earlier 109 models because the elevator authority at a perticular horizontal stab setting, was limiting the nose down capacity to an unsatisfactory maximum at full motor output. (Sounds familiar?) The aerodynamic elevator zero incidence (at a stab incidence of 1,45°) was in a position where the test pilot was not able to produce the necessary force to depress into a dive angle beyond 60°. The solution was to change the aerodynamic elevator zero incidence at unchanged & safe stabilizer incidence (in respect to the pullout capability) by doubling the trim tab area. Btw they tested to Mach 0.81.

These trim tabs then were set to produce a downforce on the elevator (trim tabs physically angled upwards), so the elevator was producing lift (physically angled downward) at the tailplane. Seems confsing at first, but is the simplest of aerodynamics. In level flight this obviously also produces more lift at the tailplane and changes the elevator neutral position to a more nose down attitude.

 

Report 109 05 E 43 "Hochgeschwindigkeitsversuche mit 109" cites:

 

This btw, is the very report you guys credit falsely with stating something about limiting nose down capability for safety reasons and protecting pilots. Since you are a fellow German I urge you to read it and tell me where exactly it states this! The reason for this test was named as:

The conclusion of this test was a completely different one, namely that you couldnt put enough force on the elevator in the first place to reach any dangerous dive angle above 60°.... Then double sized trim tabs were introduced which could yield elevator force reversal at high Mach numbers, so in turn the stab angle was limited to +1,15°, where elevator force reversal did not happen anymore.

 

This test resulted in a production line change of later models to double elevator trim tabs and limiting the stab angle to +1,15° / +1,10°.

I have posted bits and pieces of this information before, as well as that we have a G model elevator on our DCS K-4 and all of the trim difficulties we have stem from exactly these two problems! G model elevator on a K-4 and no trim tabs on the elevator, even though the quoted report above states the very function and importance of these trim tabs.

 

 

Please compare the trim tabs on a G-6 and K-4:

 

G-6

G-6.jpg

K-4

K-4.png

 

And the K-4 horizontal stabilizer setting + marked double trim tab area (verlängerte Bügelkante in german) 109 K-4 manual page 126

elevator-K4.jpg

 

 

Please also compare maximum elevator deflection at the corresponding horizontal stabilizer setting to other models... You will realize that K & G-10 models have a diferently geared elevator and using soviet G-2 documentation wont work for a correct K-4 elevator.

 

F

elevator-F.jpg

 

G-2

G-6-elevator.png

 

G-10 (important is the part G-10/U4 teilweise 27° up 24° down) so G-10/U4 with MK108 has the same elevator as the K-4

elevator-G-10.jpg

 

i would prefer g-6 elevator trim tabs looks how k-4 ended up with k-4's style trim tabs :(

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The Soviet report was related to the ELEVATOR deflection, so there is no reason to consider it irrelevant.

And, regarding "different geared elevator" - I think you mean that the stick forces are different? Then, please determine the whole elevator travel for both cases. It is not different geared", it is "different bias" in the linkage.

 

 

In German reports and also aeronautical engineering you talk about (Kraft-) Übersetzungsverhältnis which translates to gear ratio in English. This may be different in Russian, as my girlfriend tells me that in Russian rain walks instead of falls, but it is absolutely correct in German terminology.

 

Since this Soviet report links stick forces to elevator deflection and the gear ratio between a G-2 and K-4 changed, would you mind telling me how exactly it is valid? I already posted in my first post in this topic that elevator travel at zero stabilizer incidence (0°) was decreased from 33° upward and 34° downward to 27° upward and 24° downward for late 109s such as K-4 and G-10.

 

The maximum deflection angles at stab -6° are 30° up and 21° down and at stab +1,10° 26° up and 25° down. Do you want me to post the G-2 maximum deflections for comparison as well?


Edited by rel4y

Cougar, CH and Saitek PnP hall sensor kits + shift registers: https://forums.eagle.ru/showthread.php?t=220916

 

Shapeways store for DIY flight simming equipment and repair: https://www.shapeways.com/shops/rel4y-diy-joystick-flight-simming

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  • ED Team
In German reports and also aeronautical engineering you talk about (Kraft-) Übersetzungsverhältnis which translates to gear ratio in English. This may be different in Russian, as my girlfriend tells me that in Russian rain walks instead of falls, but it is absolutely correct in German terminology.

 

Since this Soviet report links stick forces to elevator deflection and the gear ratio between a G-2 and K-4 changed, would you mind telling me how exactly it is valid? I already posted in my first post in this topic that elevator travel at zero stabilizer incidence (0°) was decreased from 33° upward and 34° downward to 27° upward and 24° downward for late 109s such as K-4 and G-10.

 

The maximum deflection angles at stab -6° are 30° up and 21° down and at stab +1,10° 26° up and 25° down. Do you want me to post the G-2 maximum deflections for comparison as well?

 

Let's imagine that you have no sophisticated gear. linkage, etc. You just have a lever. Simple lever, connected to the elevator shaft. Say, you need to trim the K aircraft and, thus, deflect the elevator for the same angle as for G (for the same CoG). So, you have the same momentum at the shaft, right? And as you have the lever with the same arm (full stick travel vs FULL elevator travel ratio), you have to use the same FORCE.

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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Let's imagine that you have no sophisticated gear. linkage, etc. You just have a lever. Simple lever, connected to the elevator shaft. Say, you need to trim the K aircraft and, thus, deflect the elevator for the same angle as for G (for the same CoG). So, you have the same momentum at the shaft, right? And as you have the lever with the same arm (full stick travel vs FULL elevator travel ratio), you have to use the same FORCE.

 

In the end.. yes, as the surface remains the same, but the gears do matter and the trim tabs would definitely change the diving behavior at different speeds and CoGs.. And I wouldn't trust too much the soviet data.

Specs:

Asus Z97 PRO Gamer, i7 4790K@4.6GHz, 4x8GB Kingston @2400MHz 11-13-14-32, Titan X, Creative X-Fi, 128+2x250GB SSDs, VPC T50 Throttle + G940, MFG Crosswinds, TrackIR 5 w/ pro clip, JetSeat, Win10 Pro 64-bit, Oculus Rift, 27"@1920x1080

 

Settings:

2.1.x - Textures:High Terrain:High Civ.Traffic:Off Water:High VisRan:Low Heatblur:High Shadows:High Res:1920x1080 RoC:1024 MSAA:4x AF:16x HDR:OFF DefS: ON GCI: ON DoF:Off Lens: OFF C/G:390m Trees:1500m R:max Gamma: 1.5

 

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  • ED Team
In the end.. yes, as the surface remains the same, but the gears do matter and the trim tabs would definitely change the diving behavior at different speeds and CoGs.. And I wouldn't trust too much the soviet data.

 

 

What is the magic gear effect? You really have THE SAME GEAR RATIO from the stick to the elevator. So, you will have the same force. Bellcranks can make small nonlinearity giving small differences in gear ratio, but it does not deserve much attention, because the changes are very light.

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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Let's imagine that you have no sophisticated gear. linkage, etc. You just have a lever. Simple lever, connected to the elevator shaft. Say, you need to trim the K aircraft and, thus, deflect the elevator for the same angle as for G (for the same CoG). So, you have the same momentum at the shaft, right? And as you have the lever with the same arm (full stick travel vs FULL elevator travel ratio), you have to use the same FORCE.

 

Hey Yoyo,

I see where you are coming from, but you are missing my point. I am saying two things:

 

1. The maximum deflection changed, thus in the simplified way you broke it down the lever is longer and the stick forces will decrease at the same elevator deflection angle. The stick throw stays the same 22° pulling and 16° pushing, but at 22° stick deflection I need less force to deflect my elevator to 27° than I would need to deflect it to 33°. = higher mechanical leverage

 

2. Neutral position of the elevator in comparison to the horizontal stabilizer changed, which also alters the elevator incidence at neutral stick. G-2 has 34° down and 33° up, K-4 has 24° down and 27° up. Since the elevator actuation is linear, the neutral stick elevator position must have changed. And in this case the neutral position will have changed to a more nose down attitude. I guess this is what you call elevator bias?


Edited by rel4y

Cougar, CH and Saitek PnP hall sensor kits + shift registers: https://forums.eagle.ru/showthread.php?t=220916

 

Shapeways store for DIY flight simming equipment and repair: https://www.shapeways.com/shops/rel4y-diy-joystick-flight-simming

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  • ED Team
Hey Yoyo,

I see where you are coming from, but you are missing my point. I am saying two things:

 

1. The maximum deflection changed, thus in the simplified way you broke it down the lever is longer and the stick forces will decrease at the same elevator deflection angle. The stick throw stays the same 22° pulling and 16° pushing, but at 22° stick deflection I need less force to deflect my elevator to 27° than I would need to deflect it to 33°. = higher mechanical leverage

 

2. Neutral position of the elevator in comparison to the horizontal stabilizer changed, which also alters the elevator incidence at neutral stick. G-2 has 34° down and 33° up, K-4 has 24° down and 27° up. Since the elevator actuation is linear, the neutral stick elevator position must have changed. And in this case the neutral position will have changed to a more nose down attitude. I guess this is what you call elevator bias?

 

109K4 has 31 degrees stick travel and 51 degrees elevator travel.

I'd like to see German factory full control adjustment table first, but if I agree with the angles for G you mentioned it must be 38 degrees stick vs 67 degrees elevator.

So, the average gear ratio between stick and elevator is 1.76 for G and 1.65 K, so the difference is as much as 7%...

Anyway, as I get detailed elevator train diagram like I have for K, I will give you more detailed answer about "differences".

Ніщо так сильно не ранить мозок, як уламки скла від розбитих рожевих окулярів

There is nothing so hurtful for the brain as splinters of broken rose-coloured spectacles.

Ничто так сильно не ранит мозг, как осколки стекла от разбитых розовых очков (С) Me

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Yoyo, are you sure you are not confusing the aileron stick travel with the elevator stick travel, because in my 109 K blueprints the aileron travel is 31° and the elevator travel is still 38°. As far as I know the basic stick mechanism was never changed in production lines. Only the second bellcrank was.

 

And in my hinge moment calculations the difference is about 25% and the neutral position changed significantly.


Edited by rel4y

Cougar, CH and Saitek PnP hall sensor kits + shift registers: https://forums.eagle.ru/showthread.php?t=220916

 

Shapeways store for DIY flight simming equipment and repair: https://www.shapeways.com/shops/rel4y-diy-joystick-flight-simming

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