can not reproduce Yaw oscillation without steering input after maneuvering.

2 days ago I had the same issue as Reapers at 5:34 and 8:11.

We did some dogfights on Caucasus multiplayer. When I unload G i had the same oscillation, two times in 10-15 minutes. I tried to recreat it right after it stops but kicking two rudders had weaker effect than this oscillation. I don't know it's a bug or something else so first i posted it here to know someone else opinion.

cheers

I have had the same problem. It is like the Hornet is waddling( best description I can come up with) it has happened to me twice now.

I know it's hard to track down without a track, but looks like it's some FCS logic issue, in Reapers video i can see both rudders are moving left and right, not ailerons or elevators.

I'll try to recreate it and make a track.

Are you using rudder pedals or a Z axis on stick?

In GR, he uses Z axis but with pedals, I never saw this issue.

If you can make a track, make sure to check your controls position, might be a spike in your Z...

BR

I've tried a few times but i wasn't able to recreate this issue, i'm going to forget about that for now, especially because it's a small issue after all.

I use pedals but of high quality without any spikes and even when i tried to manually oscilate with pedals right after that issue stopped the amount of movement was far smaller then this oscilation. It has probably something to do with maneuvering or high G turning because in Reapers video he had the same issue in the same situation like my, also two times and also right after high G turns. Maybe FCS is trying to stabilise the flight in yaw axis in certain conditions overcompensating using max rudder deflection? Nevermind, there is no point debating without the track.

cheers

I like it, it looks funny.

Here's a really short track. Bonus points: I am blacked out while the wobble is occurring, so control inputs are impossible. Replication instructions:

Be very low fuel.

Pull G in any direction

Do a roll and maintain a small amount of AoA.

Stop rolling suddenly and center pedals. The goal is to get a little sideslip while you stop rolling as if you were going to snap roll.

Be between 375-425 kts and keep it there.

This track is a really short example, but you can keep it going for as long as the conditions are maintained. The exact conditions are different depending on your loadout and fuel state.

This is not just for yaw, BTW. At low fuel state the plane porpoises on it's own, too. The FCS gain is too high for the CoG and intertia moment and the plane overcorrects for everything, like it's on springs. When heavy, the opposite is true and the controls feel mushy.

Video if track not work:

wobble.trk

Here is a slightly longer track of the oscillations I was able to induce. I find that I was in the same parameters as Preendog said, except I didn't use any rudder input to induce the oscillations. In fact, I didn't use any rudder at all. As you'll also see near the end of the track, I was able to induce and maintain (for a surprisingly long time) an oscillation while also in a turn. As long as I was going about M0.6-0.7 in the turn at ~7.5 Gs, I could probably have maintained that oscillation until I ran out of fuel. Hopefully this helps diagnose the issue.

TwerkingHornet.trk

I like it, it looks funny.

 

Here's a really short track. Bonus points: I am blacked out while the wobble is occurring, so control inputs are impossible. Replication instructions:

 

Be very low fuel.

Pull G in any direction

Do a roll and maintain a small amount of AoA.

Stop rolling suddenly and center pedals. The goal is to get a little sideslip while you stop rolling as if you were going to snap roll.

Be between 375-425 kts and keep it there.

 

This track is a really short example, but you can keep it going for as long as the conditions are maintained. The exact conditions are different depending on your loadout and fuel state.

 

This is not just for yaw, BTW. At low fuel state the plane porpoises on it's own, too. The FCS gain is too high for the CoG and intertia moment and the plane overcorrects for everything, like it's on springs. When heavy, the opposite is true and the controls feel mushy.

 

Video if track not work:

This update stuff is driving me nuts. First, I know exactly what this oscillation looks like, it's been there on and off since the initial release. Looks like absolutely no yaw dampening but guess what...

I just updated to newest hotfix (10/21) and created a new simple mission just to test this again. I had 2.4 fuel, clean config. I put this thing through the wringer, yanking and banking, loaded rolls with rudder and no rudder input and every time I let go of the stick the yaw got dampened within 1 oscillation. Go figure...

Well, I spoke too soon. when I roll left or right and pull max g before the nose settled it did seem like the dampening moment got "stuck".

Don't mean to bump the thread with no additional info, but I do want to make sure that the developers see this. These oscillations are still an issue and particularly pop up when forced to engage in air combat near the end of a mission when lower on fuel, and as a result, weight. If you need more examples with track replays, I can produce more.

Just stumbled on this one while doing some unrelated tests.

Guys remember we gotta get hard data that shows the plane doesn't actually do that. Maybe it is a feature.

The data must be official and credible, but not the first result on google because that one's classified.

I feel like calling Pax or Dryden Center lol... this is probably not classified. They must have done some tests with less then 2.0 fuel and will eagerly share the results.:D

On a serious note, I need to do search before running my mouth. I remember seeing crapload of NASA articles related to high alpha testing of an early FA18 model many years ago. If this stuff is still there it might give us some clues but then... when you really think about the way it happens in DCS... I don't think it's a feature.

Guys remember we gotta get hard data that shows the plane doesn't actually do that. Maybe it is a feature.

 

The data must be official and credible, but not the first result on google because that one's classified.

The devs still haven't even acknowledged our tracks. As soon as they do that and confirm whether the oscillation is their intention or not, I'll be willing to look for information.

I have a replay track with this exact wobble.

I watched the video from Grim Reapers and what I see is that we both had flaps set to half.

I managed to extract and recompress the contents of the trackfile to make it fit.

thegulf-20240306-220326.7z

This wobbling seems to have become much more violent (seems to have a pitch component now, rather than just yaw previously) since the latest FM update.

ill try and get a track next time, but for me it seems to be triggered by flying through the wake of another aircraft while in bfm with wake turbulence turned on.

Herewobble.trk is a track and it fairly easy to reproduce. In the video I don't think I was touching the peddles or putting inputs on the stick

How do we get the attention of the devs? How do we know they even know about this?

24 minutes ago, BIGNEWY said:

Hi, we have already commented in the thread, if you are seeing an issue please attach short track replay examples. 

Kula66 posted a 1MB track file: https://forum.dcs.world/applications/core/interface/file/attachment.php?id=372740&key=32024898aea3b03c7bf7cc2fd0b900c3

On 3/9/2024 at 6:13 PM, BIGNEWY said:

Hi, we have already commented in the thread, if you are seeing an issue please attach short track replay examples. 

Hi @BIGNEWY was the track and video useful? Were the devs able to review it ok? Did it demonstrate the issue? If you need other tracks, please let me know, this can be reproduced fairly reliably.