If anyone is using a Hotas One then it’s worth checking you don’t have a fault in one of the axes.
You can do this in sensitivity settings. Watch out for any movement in any axis above or below zero with no manual input on the stick.
My Hotas One had a bad elevator twitch going on that required a 20% dead zone to quell. I reported it to TM who agreed it was a hardware warranty issue. I’ve also seen other posts on Twitter with twitches in rudder and it looked suspiciously like the same thing.
For a good few weeks after FS2020 launch I thought small aircraft were just hard to trim to steady flight until I found that the hardware was to blame.
I now have a new Hotas One which has no issues.
As you can see from this video, the rudder (and possibly the front wheel) physically moves once a speed of about 30kts is reached and then recentres again below 30kts.
Again, this looks a lot like some kind of assistance/AI interfering with aicraft control.
There’s no way the rudder can move on it’s own.
yeah but doesn’t planes have a tendency to pull to the left aswell?
Jets? No. No propeller, no (left) turning tendency.
Unplug any flight control devices you have, and try repeating the take-off with keyboard only. That will hopefully tell you where these inputs are coming from.
1 Like
It’s okay, Zendesk are looking into it as the usual ruling stuff out has already been done - there’s another post somewhere with me explaining the inputs etc. I just posted this video here for info for the original folks.
Basically:
Keyboard plugged in - nothing else
Community folder empty
Happens on a few planes, not just A320
If takeoff assist is turned ‘on’ then the rudder doesn’t move - if it’s turned ‘off’ then the rudder moves.
Turning takeoff assist ‘on’ solves the take off issue, however, on landing the rudder issue is still there so takeoffs are ok but landings are still a problem.
Tried with fresh install.
Weather set to no wind.
1 Like
After watching the video I decided to test the same on A320 today after SU6 patch. All assists were disabled as I don´t use them. I didn´t touch controls either but just let aircraft accelerate. Located at LOWG airport I tried rolling on runway at low speeds as in your video, with weather clear and wind from 225º at 5 knots (little force crosswind situation but still crosswind). I checked wind direction with Plan-G tool in real time. Test results:
-
Rolling at runway 16C departing south pedals don´t move artificially in cockpit and rudder turns to the right in the external view. Wind comes from your 2 o’clock in this case.
-
Using slew view I placed aircraft at the runway opposite side (runway 35C departing north). Again pedals don´t move but rudder turns to the left in the outside view. Wind comes from your 8 o’clock in this case.
-
Going back to runway 16C in this case I manually edit wind and set it from 225º at 0 knots (so disabled). No deviation at all from centerline occurs until aircraft reaches 100 knots.
-
Still rolling on runway when I reach 100 knots I edit wind again and set it in this case to 340º and 5 knots. In this case aircraft suffers very small deviations but still remains centered into wind direction and with centerline therefore. This is the best case for taking off with wind blowing from ahead of you.
Conclussion: the weathervane effect makes your aircraft nose willing to align into wind (and rudder surface therefore as well) if you don´t compensate it with manual pedals and/or ailerons movements. This apparently erratic movement you see is not a bug but a real physical aerodynamic effect that is confirmed to be working well by the tests in the two runway directions with same wind conditions and resulting in opposite nose/rudder movements in each test and not reproduced when wind is disabled or fully aligned with your aircraft. Results are consistent with the expected aerodynamics. If its strength is not properly calibrated in game is a different history but the effect is crearly simulated and it works as expected.
You can try a similar test to see yourself how crosswind, even if moderate, affects the control surfaces. If you do the test with a smaller aircraft like a cessna you will notice how ailerons may need to be used as well to stay centered. You should turn stick to the wind direction to prevent any lateral lift on the wings caused by incoming wind even while rolling at the runway (to the right in the first test and to the left in the second). You can also test this case yourself.
If you do the test with a tailwheeler you will notice a more intense effect as the center of gravity of the plane is displaced and the wings are not horizontal when they receive the crosswind and until the tail wheel is lifted (in the case of the A320 for instance they are horizontal since start). Also the mass is much lower which increases the disturbances created on such light planes.
This video is very long but it explains all of those things in a very clear way, including the effect of the propeller rotation. By the way is the propeller axis rotation what causes the additional forces, not the blades themselves, as explained with the bike wheel experiment they do at minute 20. Crosswind is explained at minute 12:
Cheers
Sorry, but that the wrong conclusion. The rudder can’t move on it’s own in the sim.
The flight controls are tied to your joystick/rudder pedals movement.
If you don’t move them, they don’t move in the sim either.
IRL with hydraulically powered flight controls the rudder doesn’t move due to wind.
If wind actually deflects the rudder on e.g. the A320, there’s a serious bug in the simulation!
1 Like
I mean that the tail is what turns (that´s your rudder surface).
Cheers
If you are using a USB 3.0 port for your rudder pedals/controller, try plugging into a USB 2.0 port on your computer or buy a USB port with USB 2.0 sockets. Some flight simulator peripherals do not like USB 3.0 ports. I use USB 2.0 for all my flight simulation hardware.
I am using Logitech Pro Pedals through a USB 2.0 port and they work really well, the feel is great and the toe breaks are a ‘game changer’ for me. I have just upgraded to the Logitech from old CH pedals which had an old gameport connection and required a USB to gameport adaptor, they suffered the same problem as you are reporting.
BRGDS
Charles.
Again… It´s not the controls but the physics of wind. We need to understand how it affects your control surfaces because even if wheels are touching the ground as soon as air starts to flow over them you are indeed flying already. You do it at low speeds but you are flying. Wind affects your wings and also your tail but flaps and spoliers will be affected as well if they are deployed. That´s why in some cases of strong crosswind you may prefer not to use flaps indeed to keep controllability. Any changes on those surfaces, either done by pilot or by external wind conditions will produce an effect on the aircraft.
See screenshot departing north with wind blowing from your tail sides. I disabled gust to avoid any further disturbances. Changing wind direction and just setting full throttle without touching any other control surface produces the turns to each of the directions. Your nose will want to turn into the wind direction and you always need to compensate that. With no wind or wind fully aligned with your aircraft there´s no deviation or just a small one:
With live weather enabled the wind direction and force can change faster and that produces the continuous changes you may see during takeoff (you may even get wind from left side and then some seconds after from right side until you are airbone). The higher the wind component from either your left or right side the higher the deviation you will see.
You can do the tests yourselves. Be sure to click out of the weather panel once you set new values to ensure they are applied.
Cheers
Thanks geloxo,
It seems that yes the wind direction/wind gust is affecting this, however to me it is completely wrong that a 2kt wind speed can:
A - cause the rudder to flutter like a leaf or deflect fully in one direction or another.
B - cause the aircraft to dramatically turn off in one direction.
Also, deleting the wind layer or raising the wind layer to 50,000 ft still causes this dramatic turning off the runway.
Th only way I can manipulate this is by adjusting the wind settings in-flight.
Clearly something is broken here as a 2kt crosswind doesn’t cause an airliner to careen off into the airport terminal.
The Beaufort wind scale shows wind of 1-3 knots as a light breeze with still wind vanes, and in your screenshots a wind speed of 10kts is considered a ‘gentle breeze’. Is that enough to send your 747 off piste with so much runway left?
2 Likes
Thank you for this however, I am a pilot of some forty years and understand what you are saying about ‘weathercocking’ however not to become too ‘bogged down’ with the principles of flight or other ‘dynamics’, hardware peripherals when plugged into a USB 3.0 port can produce ugly results.
Here, I have just done some ‘Googling’ and found this webpage which some of you might find interesting about using USB 3.0 ports with your peripherals. The information that DrAcorn has provided appears more likely to be caused by a hardware issue/setup.
I would be very concerned if the rudder of a real aircraft became jammed in one direction during take-off by the wind especially with one’s feet planted firmly on the rudder pedals and enough speed to maintain directional control. I would think about using another runway if x-winds were a problem!
One can counteract the weathercocking effect in a x-wind with aircraft such as gliders especially, by compensating with rudder initially until there is enough speed from the aircraft to maintain directional control/stability during take-off.
Dr Acorn says…
When Taxiing, but especially when taking off, there is significant rudder movement without any rudder input. In a more severe example the rudder was stuck completely in one direction, without any input at all.
https://goflightinc.com/information/usb-3-0-solving-connectivity-issues-with-flight-sim-devices/
BRGDS
Charles.
1 Like
That’s a misleading statement.
The ‘tail’ consists of the vertical stabilizer and the rudder.
If the rigid ‘tail’ moves, the whole aircraft yaws = weathervaning.
That’s a completely different issue than the randomly moving rudder!
2 Likes
Unfortunately I’m getting the same results with no controllers plugged in at all - my keyboard and mouse are plugged into USB 2.0 and everything else I unplugged before booting up this morning.
2 Likes
Hi Capt’ BigEye,
Oh, so you are using a keyboard to control your rudder? I think it might be a good ideal to invest in a good set of rudder pedals and controller’s assuming you don’t have any. If you are using key’s to control your aircraft, I imagine that would be more like using a switch to control your control surfaces and would not produce a smooth linear movement as using dedicated controller would.
If you need a controller, Christmas is comming soon! 
Take care, BRGDS.
Charles.
1 Like
No mate, I’ve got a thrustmaster hotas and peddle setup which seems to work fine in DCS and in msfs most of the time, I’ve just unplugged them all while I’m working out this issue/bug.
2 Likes
Hi Capt’
What Thrustmaster Hotas are you using? I have T1600 set-up which works great, the twisty joy stick works well on the rudder axis but I have it disabled as I am using dedicated rudder pedals.
Have you checked to see how many rudder axis’s you have assigned in the MSFS Control Options?.
Under your Windows Power Profile, (Power Options) if you go to advanced settings, what are your custom USB settings selected to?
If you have accidently assigned several controller axis to the rudder this might cause a problem. Anyhow it sounds like you know what you are doing and will hopefully get what is obviously an annoying problem sorted out. 
BRGDS.
Charles.
Whatever PZL… Even if the tail does not move it does not mean that the air flow pressure on its sides is not different due to changing wind conditions. And that´s what creates the lateral force on it and therefore forces plane to turn (same Venturi effect that allows a wing to get lift). Rudder and elevators just change the airflow speed on the vertical and horizontal tail surfaces as tail is in fact a couple of wings as well (horizonal and vertical) and therefore both surfaces on the tail can get different lifts, drags and forces too if they receive different airflows, the same as the wings do, even if you don´t touch any controls at all just by the existing winds and not by the airflow created by aircraft movement itself because the existing wind component is added or substracted to the airflow generated on the surfaces by the aircraft movement depending on the wind direction that you have.
As I explained some post above I´m not saying that this effect is properly calibrated in game and maybe is just too much for soft air conditions on airliners as the aviator pointed. I mean that it´s just implemented in game and it works as it should according to the physics of control surfaces so you clearly need to take it into account.
Cheers