Trimming

[greybeard_52]

In this simulator there is too much need to balance the plane: every change in speed, however small, corresponds to a change in the position of the center of lift of the wing, which in turn forces you to balance. As long as the weight of the aircraft and the CG position do not change, there is no need to trim; if the speed varies, it is compensated with the throttle. I have flown the same aircraft with the same payload several times and only once have I needed to trim. The center of lift only moves that much as you approach the speed of sound (say beyond Mach 0.7). I think the flight model should be reviewed.

[DD_Arthur]

I always enjoy a really good complaint.?

[greybeard_52]

6 hours ago, DD_Arthur said:

I always enjoy a really good complaint.?

No it's not a really good complaint. I realize that I explained myself badly and made a fool of myself... Unfortunately, these are personal sensations and habits, difficult to objectify. What I meant is that I find the simulated attitude variations as a function of speed excessive; for example, during a tack I am sometimes forced to trim, when instead I would like to steer it only with the stick.

[greybeard_52]

Trimming the airplane should help reducing pilot effort on the controls. In this simulator, on the contrary, about the pitch axis, beyond a certain control stick actuation limit (very small limit) the aircraft starts to wobble, becoming practically uncontrollable. This ends up being forced to "fly with the trim" (to pull up and dive), which is not good from all points of view (or enable the "simplified controls", which is not realistic and in any case creates other annoyances).
My joystick isn't perfect, and I've already talked about it in another thread, but it doesn't do this in Cliffs of Dover, but it does in Rise of Flight as well. I think the problem derives precisely from the fact that the flight model of BoS is derived from that of RoF, but, while almost all the aircraft of the First World War were dynamically unstable (having the CL in front of the CG - and therefore amplifying every oscillation on the pitch axis) and that's fine with it, this was definitely not true of the WW2 ones - all dynamically stable.

[LukeFF]

1 hour ago, greybeard_52 said:

Trimming the airplane should help reducing pilot effort on the controls. In this simulator, on the contrary, about the pitch axis, beyond a certain control stick actuation limit (very small limit) the aircraft starts to wobble, becoming practically uncontrollable. This ends up being forced to "fly with the trim" (to pull up and dive), which is not good from all points of view (or enable the "simplified controls", which is not realistic and in any case creates other annoyances).
My joystick isn't perfect, and I've already talked about it in another thread, but it doesn't do this in Cliffs of Dover, but it does in Rise of Flight as well. I think the problem derives precisely from the fact that the flight model of BoS is derived from that of RoF, but, while almost all the aircraft of the First World War were dynamically unstable (having the CL in front of the CG - and therefore amplifying every oscillation on the pitch axis) and that's fine with it, this was definitely not true of the WW2 ones - all dynamically stable.

 

I still don't know what you're going on about, because I can trim any of the WWII planes just fine. If you want more concrete help with this, start posting some track files showing the issue. 

[greybeard_52]

6 hours ago, LukeFF said:

... I can trim any of the WWII planes just fine.

Me too! The problem is not trimming, but being forced to do so in order not to oscillate in a tight turn, steep climb or dive. I can't figure out what's not clear about what I'm saying either. I'll give you an example: in Cliffs of Dover I turn with a Spitfire normally, without problems. In this game, if I make the same turn with the same plane, I have to "help" myself with the trim, otherwise the plane starts pitching! Naturally, upon exiting the turn I then have to re-trim for level flight. It's not normal!

 

6 hours ago, LukeFF said:

... start posting some track files showing the issue.

This has been done before and those who have seen it notice the wobble of the plane and even of the elevators, but can't figure out if it's my hand shaking on the joystick or a flaw in the flight model. I support this second hypothesis.

[DEDMANcjp]

have you tried adjusting the elevator travel curve and dead spot in key mapping?

[Hoss]

5 hours ago, greybeard_52 said:

Me too! The problem is not trimming, but being forced to do so in order not to oscillate in a tight turn, steep climb or dive. I can't figure out what's not clear about what I'm saying either. I'll give you an example: in Cliffs of Dover I turn with a Spitfire normally, without problems. In this game, if I make the same turn with the same plane, I have to "help" myself with the trim, otherwise the plane starts pitching! Naturally, upon exiting the turn I then have to re-trim for level flight. It's not normal!

 

This has been done before and those who have seen it notice the wobble of the plane and even of the elevators, but can't figure out if it's my hand shaking on the joystick or a flaw in the flight model. I support this second hypothesis.

Use your rudder in turns, keep the ball centered, and yaw trim is not an issue. Everytime you touch the throttle you'll have a trim problem. Trim for level flight, then either increase or decrease throttle and watch that ball move left or right. 

[greybeard_52]

1 hour ago, DEDMANcjp said:

have you tried adjusting the elevator travel curve and dead spot in key mapping?

Yes, I did, but with no avail.

1 hour ago, Hoss said:

Use your rudder in turns, keep the ball centered, and yaw trim is not an issue. Everytime you touch the throttle you'll have a trim problem. Trim for level flight, then either increase or decrease throttle and watch that ball move left or right.

I fully agree with your point of view; not easy to actuate, though, this "academic" turn during a dogfight. I should find also the way to have the "ball" in sight together with my target. I must work on it. Anyway, my problem is about pitch axis, not yaw, and I still can't understand why it happens to me only with BoS...

[PO_Baldrick]

This is where I get confused about trimming.

 

In my simple mind the trim operates on the same controls as your stick and rudder pedals and is a fine tuning mechanism to lessen the workload in using the controls - i.e. having to hold the stick and pedals in a given position accurately.

 

I am not sure if trim can add to a control movement - e.g. does full rudder right with full trim right extends the rudder movement?

 

Otherwise I don't see why you can't achieve everything in a turn using the stick and rudder without needing to trim, it just needs accurate controls.

[Hoots]

2 minutes ago, PO_Baldrick said:

This is where I get confused about trimming.

 

In my simple mind the trim operates on the same controls as your stick and rudder pedals and is a fine tuning mechanism to lessen the workload in using the controls - i.e. having to hold the stick and pedals in a given position accurately.

 

I am not sure if trim can add to a control movement - e.g. does full rudder right with full trim right extends the rudder movement?

 

Otherwise I don't see why you can't achieve everything in a turn using the stick and rudder without needing to trim, it just needs accurate controls.

 

It shouldn't add as it simply deflects the control surface, so it can't move it further than full extension if that makes sense?

 

[PO_Baldrick]

3 minutes ago, Hoots said:

 

It shouldn't add as it simply deflects the control surface, so it can't move it further than full extension if that makes sense?

 

Yes it does make sense thanks!

I can see the value of trimming, to guarantee the controls are in the optimum place without having to hold the stick or rudders in the perfect position. However, I don't see why this shouldn't be achievable purely with the stick or rudder. Unless the stick and rudder are a more coarse control method than the trim.

[Hoots]

Just now, PO_Baldrick said:

Yes it does make sense thanks!

I can see the value of trimming, to guarantee the controls are in the optimum place without having to hold the stick or rudders in the perfect position. However, I don't see why this shouldn't be achievable purely with the stick or rudder. Unless the stick and rudder are a more coarse control method than the trim.

 

Trim is just a way of relieving forces on the stick, so makes for more accurate flying. So you can do it with the stick, it just takes concentration and effort that is better used elsewhere

[PO_Baldrick]

34 minutes ago, Hoots said:

 

Trim is just a way of relieving forces on the stick, so makes for more accurate flying. So you can do it with the stick, it just takes concentration and effort that is better used elsewhere

Thanks, my background is sim racing where you are pretty much constantly working the wheel and pedals so I apply the same approach to dogfighting. Having another set of controls operating the same mechanism makes sense to me for level flying or a period of constant turn but in dogfighting with lots of changes in direction and speed it just seems easier to do it all with the stick and pedals in my head at least!

[AEthelraedUnraed]

3 hours ago, Hoots said:

It shouldn't add as it simply deflects the control surface, so it can't move it further than full extension if that makes sense?

Not necessarily; some trims such as in the Bf-109 do indeed move the whole control surface, but many others have additional "tabs" on their control surfaces that work just like the control surfaces themselves. I think they do add to the deflection of the main control surface, although the effect will be minimal in comparison. EDIT: on second thoughts, I think the Bf-109 trim moves the stabilizer itself rather than the elevators. Anyhow, there exist many forms of trimming, each with their own characteristics.

 

2 hours ago, PO_Baldrick said:

Thanks, my background is sim racing where you are pretty much constantly working the wheel and pedals so I apply the same approach to dogfighting. Having another set of controls operating the same mechanism makes sense to me for level flying or a period of constant turn but in dogfighting with lots of changes in direction and speed it just seems easier to do it all with the stick and pedals in my head at least!

That's correct; trimming is mainly intended for level flight and has limited use in combat, although some people use it to improve their gunnery accuracy.

 

Back on topic. @greybeard_52, I still haven't a clue what you're talking about. I don't have any kind of wobble, no matter how I trimmed my aircraft. Are you sure you're not simply close to a stall?

 

EDIT: thinking a bit more about this issue, could it be that your joystick glitches? It's possible those other games have some kind of filtering in place where IL2 doesn't (both choices have their advantages). That would explain why you're experiencing this problem only in IL2. Especially if you have an old or worn potmeter-based joystick, this sounds like a plausible explanation.

Edited March 7, 2023 by AEthelraedUnraed

[[CPT]Crunch]

If your not trimmed with rudder, you still have a slip condition when your pedals are neutralized.  Is that a place you really want to be in a dogfight?  You can't feel it in the sim, only see it, just fix it and get it over with, even a ball close helps.

 

Elevator, same thing, that's what your VVI is there for since you don't have an ass programmed to feel it with in sim.  Trim the VVI for zero climb if you want any hope of reaching maximum flat line speed.  If you want to climb with a controlled or best rate, your going to have to trim for it.  If you want to dive red lined up to maximum rated speeds and do it alive in certain frames, think about trimming.

[greybeard_52]

12 hours ago, AEthelraedUnraed said:

I still haven't a clue what you're talking about. I don't have any kind of wobble, no matter how I trimmed my aircraft.

Of course, if you don't have any kind of wobble, no matter how you trimmed your aircraft, you can't see what I mean. What I'm struggling to explain is that I must reach same elevators position with a bit of stick and much more of trim to avoid wobbling (this latter obviously devastating during a dogfight - while you're aiming to your target).

 

12 hours ago, AEthelraedUnraed said:

could it be that your joystick glitches?

It could be (I see some uncertainty in its movement in Windows test).

 

12 hours ago, AEthelraedUnraed said:

It's possible those other games have some kind of filtering in place where IL2 doesn't (both choices have their advantages).

I too suspect so.

 

12 hours ago, AEthelraedUnraed said:

Especially if you have an old or worn potmeter-based joystick, this sounds like a plausible explanation.

Indeed, it is a Thrustmaster Hotas X. I bought also a new one (Hotas 4), getting same problems.

[AEthelraedUnraed]

On 3/8/2023 at 1:58 AM, greybeard_52 said:

It could be (I see some uncertainty in its movement in Windows test).

In the game settings is a slider for the joystick filter length. Move it up a bit and see if it helps.

 

(Note: the filter will delay the input response a bit. For people with a modern, high-quality joystick, it's generally best to keep it at 0. With old or cheap joysticks, moving it up a bit can help prevent jitter.)

[Bars-]

06.03.2023 в 20:07, greybeard_52 сказал:

 In this game, if I make the same turn with the same plane, I have to "help" myself with the trim, otherwise the plane starts pitching! Naturally, upon exiting the turn I then have to re-trim for level flight. It's not normal!

 

Lift decreases while banking, so you need more pitch or more airspeed in compare to balanced straight and level flight. 

 

Airspeed is a key factor. It can change a lot and fast. If you've got your airplane well trimmed for straight and level flight with zero vertical speed any airspeed change will cause vertical speed increase or decrease. So new trim settings will be necessary. That is normal even during 15 degree bank angle to pull up a little bit or to add elevator trim a bit. 

 

There is another thing.  In game such as in real life balanced level flight with constan elevator trim setting is possible not on every airspeed and gross weight. Comparatively low airspeed and heavy fuel and ammo load enables level flight with constant elevator trim setting. But if your airspeed is closer  to maximum and/or you've got less fuel you will not be able to fly level with constant elevator trim setting. You gonna need to change trimming constantly. Thats why close formation flying for example  is much easier when all airplanes have got 100% fuel, heavy bombs and leader sets his engine power as far from maximum as he can. 

[greybeard_52]

On 3/10/2023 at 1:24 AM, AEthelraedUnraed said:

In the game settings is a slider for the joystick filter length. Move it up a bit and see if it helps.

 

(Note: the filter will delay the input response a bit.

Tried, but (as you warn) I'm annoyed by the consequent delay.

 

On 3/10/2023 at 1:24 AM, AEthelraedUnraed said:

For people with a modern, high-quality joystick, it's generally best to keep it at 0. With old or cheap joysticks, moving it up a bit can help prevent jitter.)

I think it is unfair forcing the customer to buy a joystick having a three digit price to get basic control in flight model.

[PO_Baldrick]

3 hours ago, greybeard_52 said:

 

I think it is unfair forcing the customer to buy a joystick having a three digit price to get basic control in flight model.

Not sure what options there are. If a joystick jitters then the only option is to smooth out the inputs with a filter but that inevitably deadens the reaction to movements.

[AEthelraedUnraed]

5 hours ago, greybeard_52 said:

I think it is unfair forcing the customer to buy a joystick having a three digit price to get basic control in flight model.

Nobody's forcing you to buy anything.

 

Your comment is a bit like taking a 20 year old Fiat Panda to the Nürburgring and complaining about your track times. If you want good performance, you need good hardware. Good hardware costs money. That's got nothing to do with fairness, it's just reality. There's nothing IL2 can do about that - if you want to complain, you should direct that towards the joystick vendors for having inflated prices, your employer for paying too little, or your government for the state of the economy.

 

As said, it's possible to filter the joystick response to remove jitter, but that causes other issues. Try to tweak the various joystick settings, both in-game and in Windows, until you've found some golden combination that works for you.

[greybeard_52]

2 minutes ago, AEthelraedUnraed said:

Your comment is a bit like taking a 20 year old Fiat Panda to the Nürburgring and complaining about your track times.

I would just turn without being forced to use trim; I don't think this is like to win a grand prix with a Fiat Panda. For this reason I was speaking of BASIC control.

[AEthelraedUnraed]

5 minutes ago, greybeard_52 said:

I would just turn without being forced to use trim; I don't think this is like to win a grand prix with a Fiat Panda. For this reason I was speaking of BASIC control.

And you can turn without having jitter. All you have to do is increase the filter length.

 

The problem is that you want your joystick response to be both smooth and fast. With cheap joysticks, that combination just doesn't exist. The solution is simple - get a better joystick. If you cannot afford that, you'll have to settle on some kind of compromise between smoothness and delay. IL2 and Windows give plenty of options to adjust the joystick response to your liking, but just like you'll never be able to make a Fiat perform like an F1 car, you'll never be able to make a cheap joystick perform like an expensive one.

 

Is it fair? No, just like it isn't fair we all gotta die some day. But it's just the way it is, and complaining about it won't change a thing.

[AEthelraedUnraed]

Thought I'd add some background info on the mathematical reasons behind this, as it's somewhat of my expertise.

 

Below are two simulated joystick signals, with various causal filters. The noise you can see on the right comes from various sources, and will be less prevalent for high-end sticks. In other words, a cheap stick might look like the right side while an expensive one might look more like the left.

The various filters are a simple summation (length 25) and a raised-cosine filter for lengths 25 and 5. As you can see, the longer raised cosine filter (yellow line) is able to filter out the noise rather well and is able to recover the true signal almost completely (right hand side). Even the slightly computationally cheaper summation filter (red line) does a decent job.

 

However, as you can see, the good performance of the longer filters comes with a large delay, as well as a slightly different shape. One could solve this by shortening the filter, but as is visible from the length 5 raised cosine filter (the purple line), this then does a much less good job at filtering out the noise.

 

If you're able to find a filter that combines the delay of the purple line with the noise-reducing qualities of the yellow line, this would earn you a nobel prize. Personally I don't have so high hopes for myself and would rather save up for a new joystick.

[greybeard_52]

7 hours ago, AEthelraedUnraed said:

With cheap joysticks, that combination just doesn't exist.

Dear friend,
you say some very sensible things and you document them well. I do not pretend to possess the absolute truth and I am convinced in a good part of what you say; I have to keep looking for a better compromise. The only thing that leaves me in doubt is that with Cliffs of Dover I NEVER HAD THIS PROBLEM and I always left the default settings. If there was a career mode and it wasn't replete with bugs, I confess that I would only play that.
I will also keep in mind the possibility of a higher technology joystick; maybe when the person who stole everything from me and who defends himself by asking me for more money will receive justice (in a world where guarantees and forensic ruthlessness no longer overturn the truth).
I found this video which doesn't make me feel alone about the problem; evidently wobbling is a known flaw of this simulator. I've also heard rumors that it also affects DCS and War Thunder.

 

[LukeFF]

5 minutes ago, greybeard_52 said:

I found this video which doesn't make me feel alone about the problem

 

It was posted 6 years ago. Lots has changed since then. ?

 

No offense, but if this was that big of a problem, you'd see a lot more people posting about it here.

[PO_Baldrick]

9 hours ago, greybeard_52 said:

I would just turn without being forced to use trim; I don't think this is like to win a grand prix with a Fiat Panda. For this reason I was speaking of BASIC control.

Again I come from a sim racing background, where you make constant small corrections mid corner as grip changes. For me adding trim whilst turning is just a small correction I would naturally make on my stick.

 

Jittery pots on steering wheels and deadzones are a massive problem for sim racers but is largely a thing of the past as hardware has improved. I still have some switch cleaner spray in the loft I used on my old wheel!

[AEthelraedUnraed]

3 hours ago, greybeard_52 said:

Dear friend,
you say some very sensible things and you document them well. I do not pretend to possess the absolute truth and I am convinced in a good part of what you say; I have to keep looking for a better compromise. The only thing that leaves me in doubt is that with Cliffs of Dover I NEVER HAD THIS PROBLEM and I always left the default settings. If there was a career mode and it wasn't replete with bugs, I confess that I would only play that.
I will also keep in mind the possibility of a higher technology joystick; maybe when the person who stole everything from me and who defends himself by asking me for more money will receive justice (in a world where guarantees and forensic ruthlessness no longer overturn the truth).
I found this video which doesn't make me feel alone about the problem; evidently wobbling is a known flaw of this simulator. I've also heard rumors that it also affects DCS and War Thunder.

 

The other sims likely have different default setting for filtering and sensitivity. It may be the case that IL2 has its default settings tuned for a higher quality joystick than CloD.

 

It's good you bring up that video, since I completely forgot to mention sensitivities as well. That means there are three different settings you can adjust:

- Windows game controller settings: https://www.howtogeek.com/241421/how-to-calibrate-your-gaming-controller-in-windows-10/

- Filter in the in-game settings;

- Sensitivity and dead zones in the in-game controls menu (as in the video).

 

Depending on your joystick, there may in addition be specialised software to adjust control responses on the driver side, but that's usually only the case for the more expensive models.

 

If you have really excessive jitter even when your sensitivity is low, you may have dirty contacts, in which case cleaning the potmeters with electrical contact cleaner can solve the problem: https://www.reddit.com/r/hotas/comments/hv008e/how_should_i_clean_or_replace_hotas_4/.

 

Somewhere in all these settings, I'm sure there is a golden combination that works for you. Good luck

[69th_Mobile_BBQ]

I have Thrustmaster rudders pedals (the budget ones) that auto-calibrate after you push them left and right plus, a X52pro HOTAS that also auto-calibrates and can't be calibrated manually.

Neither of these controllers are "high fidelity".  No matter how I set them, there is either a large amount of wobble or input lag. The best I can dial them in is not great.  That said, one thing I found in the menus was the "Joystick Noise Filter" that seems to help and lower the need for extreme sensitivity curves settings in the controls menu. 

[greybeard_52]

23 hours ago, LukeFF said:

No offense, but if this was that big of a problem, you'd see a lot more people posting about it here.

Sure! I say that's a problem for me. Obviously it depends on personal hardware, peripherals, sensibility and a lot more of subjective things. To be honest, though, OTOH and no offense for anyone, I too notice how certain objective defects in this simulation remain unnoticed even by testers.

[greybeard_52]

18 hours ago, AEthelraedUnraed said:

Somewhere in all these settings, I'm sure there is a golden combination that works for you. Good luck

Many thanks for all the tips!

6 hours ago, 69th_Mobile_BBQ said:

That said, one thing I found in the menus was the "Joystick Noise Filter" that seems to help and lower the need for extreme sensitivity curves settings in the controls menu.

Thanks! I must try again finding  some suitable filter setting.

[Knarley-Bob]

If I may ask, why doesn't the "Trim" stay where you put it? I'm all trimmed out, flying great, then we get into a tussle, and IF I survive, and don't get shot up, the trim is all over the place. Sometimes it goes out of my setting in flight too. I understand if I get shot up, that will change things. But one's trim settings shouldn't be changing, unless changed, no? OR, is that a normal thing? I'll admit, I am NOT a real pilot.

 

KB

Edited March 18, 2023 by Knarley-Bob

[AEthelraedUnraed]

44 minutes ago, Knarley-Bob said:

If I may ask, why doesn't the "Trim" stay where you put it? I'm all trimmed out, flying great, then we get into a tussle, and IF I survive, and don't get shot up, the trim is all over the place. Sometimes it goes out of my setting in flight too. I understand if I get shot up, that will change things. But one's trim settings shouldn't be changing, unless changed, no? OR, is that a normal thing? I'll admit, I am NOT a real pilot.

 

KB

What do you mean? Your trim shouldn't change unless you set it yourself.

 

What does change however, is how much trim you need to fly level. First of all, if you speed up, your plane's nose will go up so you'll require more downwards trim to compensate for that - and vice versa. Also, as your plane consumes fuel, this will change the balance and hence the required trim of the aircraft.

[Knarley-Bob]

1 hour ago, AEthelraedUnraed said:

What do you mean? Your trim shouldn't change unless you set it yourself.

 

What does change however, is how much trim you need to fly level. First of all, if you speed up, your plane's nose will go up so you'll require more downwards trim to compensate for that - and vice versa. Also, as your plane consumes fuel, this will change the balance and hence the required trim of the aircraft.

That does make sense. Do the tanks have a flow tube connection to help keep them at the same level, as like some motorcycles do? Or does one need to keep switching from one tank to another? But at any rate, constantly fiddling with the trim sounds like a normal thing whilst flying then. I'm cool with that. One needs to ask to learn.

Thank you

[ACG_Cass]

A good way to think of this is imagine you are driving a car with no power steering where both front wheels are pointing slightly to the left. In order to drive straight you would have to turn the steering wheel to the right. The faster you go, the more force you would need to turn the wheel. If you slow down and put the same amount of force in, your going to end up with too much and will turn right. You need go adjust those forces so you can remain straight.

 

That's what's happening but from a lift, up/down perspective. With the trim tabs on the control surfaces acting as the force on the wheel. There are a lot of competing forces from different surfaces of the plane and most are designed with a speed on mind where all trim in neutral and you can fly with the "wheel straight".

 

It's important to note that in IL2, how much you move your stick does not correlate to how much the in game stick moves. Its more complex than this but its generally best to think of your stick as you telling the pilot how hard you want to pull. Stick forces get enormous at high speed in these aircraft and IL2 simulates that by having limits on how hard a pilot can pull. That's where trim can be important in terms of pulling at high speed.