Pitch Trim Sensitivity Opinion

thanks. so the Viper does not have such a feature (planed)?

The trim is definitly WIP. And I notice the yaw to the right on takeoff as well. I've started trimming my rudder 8-10 clicks to the left before I roll.

I tried that out of curiosity and had the impression I was running a P-51D with twice the power it actually has, pulling to the left a lot. Well, my fps in VR are quite lowish which seems to have quite an impact to the trim rate, especially with the Viper.

Literally, when carrying the "Teapod", it rolls to the right untrimmed. One single tap of aileron trim LWD and it rolls to the left instead. Just can't hit the spot in between at all.

I've run into this more recently. When trying to trim the jet say after firing a heater, it is very difficult to get the trim wheel to move one click when clicking the hat. Regardless of direction. I've watched the wheel which is on the left console at the aft section while clicking the hat switch and it's almost acting like an axis instead of a switch. The wheel will move multiple clicks for what feels like a very short press of the trim hat. I think it needs a longer delay programmed in to the binding. In other words I should have to hold the trim hat in position for a longer period of time (measured in milliseconds so not really a long time) before the button press is activated again. It should be a pretty simple fix of adjusting the delay. If it's in a LUA file we can probably adjust it ourselves.

As to trimming the Viper in general, it only takes a lot if its unbalanced by armament, damage or tanks. This applies to both real world and the behavior I've experienced in the module. If balanced out you will rarely need to trim. That said, when I do trim, I usually over trim on accident because of the above behavior.

Trim in any axis is waaaay too sensitive in all modules of DCS. Something that really needs to be worked on.

I am very happy trim sensitivities with all modules but viper. my plane rolls to a side because of a payload imbalance, i apply counter trim, and even one click trim makes the plane roll to other side

I am very happy trim sensitivities with all modules but viper. my plane rolls to a side because of a payload imbalance, i apply counter trim, and even one click trim makes the plane roll to other side

Next time you trim, watch the trim wheel on the back of the left console and see how many clicks it's moving when you press the trim hat. If everyone does this we can confirm it's and input delay problem and an easy fix.

The stick trim switches operates a motor which moves the wheel on the trim panel. This is an indirect mechanical relationship. Perhaps the wheel displacement per time stick switch activation is not a directly proportional relationship.

The practical effect would be that small taps of the switch would move the wheel a smaller amount than if it the wheel acceleration was infinite. It's a hypothesis.

In this track I have one wing completely filled, and one wing completely empty. I can barely control the jet on the ground, and my takeoff is HORRIBLE.

In the air it flies hands off. Please view my track and tell me what the issue is.. I can fly this thing hands off no problem and I don't understand why you guys are having a problem. Take control. try it for yourself.

https://drive.google.com/file/d/1n4RW4WO8XhzEpoxiZNSkcGygFeePvWRJ/view?usp=sharing

I begin the track with a trim test. You can see that pitch and roll move at different rates. This was not the case on release. Control indicator is visible. Interestingly the severe asymmetry makes taxiing and takeoff extremely difficult. The takeoff was handled very badly by me, with a distraction looking in the cockpit causing me to have an excursion, which I decide to continue in a "hail Mary" moment LOL. At rotation I have full control deflection just to maintain control. After wheels up some light trimming and I can relieve all control deflection for long periods of time. I don't think you can get worse asymmetry than I had.

My joystick is a Logitech Extreme 3D Pro. I use a button on the base as a modifier which turns the single Hat switch into the Trim Hat. Rudder control is very rough considering I have controller spike issues with the twist action. I thought the ground handling hilarious.

This is NTTR, Nellis instant action.

In this track I have one wing completely filled, and one wing completely empty. I can barely control the jet on the ground, and my takeoff is HORRIBLE.

 

In the air it flies hands off. Please view my track and tell me what the issue is.. I can fly this thing hands off no problem and I don't understand why you guys are having a problem. Take control. try it for yourself.

 

https://drive.google.com/file/d/1n4RW4WO8XhzEpoxiZNSkcGygFeePvWRJ/view?usp=sharing

 

 

I begin the track with a trim test. You can see that pitch and roll move at different rates. This was not the case on release. Control indicator is visible. Interestingly the severe asymmetry makes taxiing and takeoff extremely difficult. The takeoff was handled very badly by me, with a distraction looking in the cockpit causing me to have an excursion, which I decide to continue in a "hail Mary" moment LOL. At rotation I have full control deflection just to maintain control. After wheels up some light trimming and I can relieve all control deflection for long periods of time. I don't think you can get worse asymmetry than I had.

 

My joystick is a Logitech Extreme 3D Pro. I use a button on the base as a modifier which turns the single Hat switch into the Trim Hat. Rudder control is very rough considering I have controller spike issues with the twist action. I thought the ground handling hilarious.

 

This is NTTR, Nellis instant action.

That's odd it didn't take much trimming. While the Viper is full on FBW, it isn't that good! Lol. You should have had to trim an equal amount of deflection as the stick was on take off. It can trim that much but not on its own. I've not seen the FBW system help that much before.

The stick trim switches operates a motor which moves the wheel on the trim panel. This is an indirect mechanical relationship. Perhaps the wheel displacement per time stick switch activation is not a directly proportional relationship.

 

The practical effect would be that small taps of the switch would move the wheel a smaller amount than if it the wheel acceleration was infinite. It's a hypothesis.

Do you know if it's modeled that way in the software? Typically an input like a joystick will have a delay set for the buttons. This is if they're to have not only a momentary push button but a press and hold feature. In this instance it's an easy fix of adjusting the delay. If the sim is modelling the actual electromechanical functions of the trim system in the Viper, that's gonna be a bitch to find and fix..

Not at all. I don't know if it's a realistic effect to model. I doubt that the current modeling is curved in this way. The simplest modeling would be constant change rate. If 1 second of trim switch duration yields 100 units of trim wheel movement then I'm sure 0.5s is 50 units, 0.1s is 10 units, 0.01s is 1 unit. In this scheme the ratio of wheel movement per duration switch duration is constant.

What I'm suggesting isn't a delay but an acceleration. If it took 0.2 sec for the wheel to fully accelerate to steady rate then the ratio would be lower for brief taps than for longer ones. The practical effect would be small adjustments would be less sensitive. While this is plausible, I don't know if it's true. The trim wheel motors could be effectively instantaneous in acceleration and this effect not observable.

Pitch Trim sensitivity work-around

I know this is not like IRL, but I want to fly without fighting the pitch trim behaviour. I have added bindings to the joystick POV nose-down and nose-up with LCtrl as a modifier, binding them to the manual trim panel knob. Plus, I have reduced the "speed" of that knob by changing the two "value_pressed" in "default.lua" from 0.3 to 0.1. This gives me a Coarse/fine adjustment of the pitch trim and takes the hassle away until hopefully ED come up with something better.

I know this is not like IRL, but I want to fly without fighting the pitch trim behaviour. I have added bindings to the joystick POV nose-down and nose-up with LCtrl as a modifier, binding them to the manual trim panel knob. Plus, I have reduced the "speed" of that knob by changing the two "value_pressed" in "default.lua" from 0.3 to 0.1. This gives me a Coarse/fine adjustment of the pitch trim and takes the hassle away until hopefully ED come up with something better.

Excellent temporary fix!

Can you guys please post a track of your trim issues please.

Many of us are not having it and don't understand what you're seeing.

EDIT: I've had a "shower thought" that maybe some of you guys are "Fighting the FLCS" and this results in the instability you're seeing? Similar to how many users have issues fighting the autopilot of the KA-50 when they first get it (I know I certainly did, and I do remember fighting the FLCS in the 16).

The only issue I have is the Trim hat input being too much. Nothing drastic though, for the most part it flies like I'm used to on another sim. At least with regards to trimming it. I drive the Viper like I stole it and she never complains for the most part.

I too have been having this issue recently. If I adjust the roll trim at all, say after firing an AIM-120, then I completely screw up the flight characteristics for the rest of the flight. After using trim it causes the aircraft to either roll left or right without ever being able to find the sweet spot. This is no matter how short or light a press of the trim hat is. I am wondering if this is something that needs to be worked out on ED’s side or if this is somehow pilot error?

Keep in mind that I have no issues with the A-10C or F/A-18C. The trim controls on those aircraft are fantastic. It seems like as of right now the F-16C HOTAS trim is way sensitive, and sensitive to the point that I opt to not use it and just fight the roll until my load is once again symmetric.