109 elevator trim

[Flanker35M]

S!

So the trim was used in Bf109 and other planes to compensate the changing flight conditions, like in any other plane. The extent to which pilot used elevator trim in a Bf109 can only be speculated, some might have used more than others.

Finns did use elevator trim to pull out from high speed dives as the controls went almost solid. But then we are talking about speeds excess 700km/h, not the usual 300-500km/h.

I also read from a P51D pilot's combat story that he did fiddled with trims even in combat to achieve best performance. And a Pony had more trims than Bf109 So the thing is that these pilots were so used to the controls and their location that could operate them blindfolded and quickly because of their training and experience. This is hard to model into a game as there is no absolute truth how it works. We have the travels, rotations etc. but the rest..?

In the end what we get is how the developer interprets these things and puts them in the game. A compromise of something hard to model otherwise IMHO.

[Robo.]

Originally Posted by SlipBall

If in fact the wheel revolutions are correct as you presented, then I would agree the game model is wrong...but I think that you would need more proofs, other than an authored book as a reference.

Yes they are correct and yes the game model is wrong I am afraid.

Why do you find the above reference (especially RAE tests) untrustworthy?

[Robo.]

Originally Posted by Flanker35M

So the trim was used in Bf109 and other planes to compensate the changing flight conditions, like in any other plane. The extent to which pilot used elevator trim in a Bf109 can only be speculated, some might have used more than others.

Of course, but it is apparent that the 109 elevator trim was rather specific with the design and purpose. Feel free to google for French tests of the same captured Emil and what they state regarding elevator trim (when compared to D.520 iirc)

Originally Posted by Flanker35M

Finns did use elevator trim to pull out from high speed dives as the controls went almost solid. But then we are talking about speeds excess 700km/h, not the usual 300-500km/h.

Not just Finns but everybody There is specific paragraph regarding trim wheel use in a dive in the manual. (Sturzflug) You set it incorrectly and you can end up in very unpleasant crater situation. There is also factory test of the dive characteristics with different trim settings out there. This was overly important of course.

Originally Posted by Flanker35M

I also read from a P51D pilot's combat story that he did fiddled with trims even in combat to achieve best performance. And a Pony had more trims than Bf109

American a/c have had a bit different approach to trims. While we're at the Finns, have a look how they compared US made Brewsters and MTs regarding trims.

Originally Posted by Flanker35M

This is hard to model into a game as there is no absolute truth how it works. We have the travels, rotations etc. but the rest..?

It is hard to model, but still possible. What we have got at the moment is not good enough imho, hence this thread.

[robtek]

How long does the full travel from -3 to +8 degree take in game?

I only know for shure that the reaction is much slower than my trim axis.

I think 4 quarter turns a second is normal for a pilot familiar with the 109, that would make it 5 seconds for a full change, which never would happen.

So, to trim nose up one might need 2, max. 3 degree + on the elevator, as it is only needed to get the lead for a few seconds, taking 1 turn of the wheel or about 1 second and is easily feasible, imo.

[5./JG27.Farber]

Originally Posted by Robo.

I am not confusing anything, the relevance is in the position and access to the wheel control. 5 full turns (or 4 three-quarter turns) were required to adjust the full 12 degree range.

But if the aircraft in level flight is trimmed, lets say 0, then why would the pilot be going for the full 12 degrees? So its not 4 3/4 turns is it? It 1 or 2 3/4 turns! The wheels as I have read where quite accesable.

I feel this has been a valuble learning experience for me and thanks for letting me know about this. I will give it a try next time im flying. Ill let you know how I get on but I dont think it will change allot for me.

[Robo.]

Originally Posted by 5./JG27.Farber

But if the aircraft in level flight is trimmed, lets say 0, then why would the pilot be going for the full 12 degrees? So its not 4 3/4 turns is it? It 1 or 2 3/4 turns!

This is what I wrote before (post 36)

''I can only assume that it was full 2 revolutions from neutral position to full up. Now watch the animation (less than one rev) and the immediate effect we have got in game. Neutral position (0), +3 was nose down, -8 was full up - assuming the 0 is neutral for cruise flight, it would be even more than 2 full revs to get from neutral to full up, it would be more like 3 and half full revolutions. I would need to verify this and do some more research but I am sure someone will have that knowledge.''

Originally Posted by 5./JG27.Farber

I feel this has been a valuble learning experience for me and thanks for letting me know about this. I will give it a try next time im flying. Ill let you know how I get on but I dont think it will change allot for me.

Yeah I find this also very interesting.

[Osprey]

Very interesting responses, I am pleased that most people understand that I am making the point to make our game more sim and less game. It's not about advantage but reality.

Just to be clear, my argument is that the trim control operational difficultly and speed of operation should be replicated for all aircraft. Thus if indeed it took a pilot several seconds to adjust his trim 3 or 4 degrees by turning a 12inch wheel then there's no reason why, for example, a flick of a thumb on the joystick should send it 6 degrees in 2 seconds. Any action on any aircraft should have a bug raised if such exploit is found.

~S~


As a side note I had to report Grathos for his quite disgusting reply, thoroughly rude and obtuse, I think it says more about him than me. @Grathos, don't ever '~S~' me again.

[Crumpp]

Aerodynamic forces change the feel and operation of controls. They are designed to work under those forces.

That is also why a very small amount of trim makes for a large adjustment in trim forces in most aircraft. It won't take several seconds to adjust the trim forces in flight.

[drewpee]

Originally Posted by Robo.

I disagree, I find this discussion friendly and interesting. An issue has been raised, no one has used the word 'cheat'. There is no argument at all and it is clear that the trim behaviour is questionable and unrealistic.

Sorry the word cheat was used and implied. Isn't that the point of this discussion. That's what it sounds like to me. I didn't say it wasn't friendly. I just gave my opinion.

[Robo.]

Originally Posted by Crumpp

Aerodynamic forces change the feel and operation of controls. They are designed to work under those forces.

Yes of course.

Originally Posted by Crumpp

That is also why a very small amount of trim makes for a large adjustment in trim forces in most aircraft. It won't take several seconds to adjust the trim forces in flight.

Have you got any specific information regarding the 109 trim wheel operation?