Flight Model - Pushing cyclic forward in forward flight causes severe roll to left. Video and Track.

[S. Low]

Link to track:

https://drive.protonmail.com/urls/9Y67RN8N6G#ZzO4Ymf70pQ8

 

Thank you

[ruprecht]

I have noticed similar, but I put it down to a combination of gyroscopic precession and not properly understanding how the stabilator interacts with the main rotor. 

When you nose down, you're applying a downforce at the front of the disc, and an upforce at the back of the disc. Gyroscopic precession will apply those 90 deg in the direction of rotation, so that's up on the right and down on the left, which is what you're seeing.

Essentially, gotta take it easy with a flying tank. I'm not sure this is a bug.

[Vakarian]

1 minute ago, ruprecht said:

I have noticed similar, but I put it down to a combination of gyroscopic precession and not properly understanding how the stabilator interacts with the main rotor. 

When you nose down, you're applying a downforce at the front of the disc, and an upforce at the back of the disc. Gyroscopic precession will apply those 90 deg in the direction of rotation, so that's up on the right and down on the left, which is what you're seeing.

This may be just my lack of knowledge, buuuuut in these modern days aren't controls set-up in a way if I do cyclic forward, they apply that change on the swashplate in a way that accounts for the gyro precession? If that weren't the thing, then if you wanted to fly forward, you would do cyclic left/right (depending what you fly) instead of cyclic forward which you do. 

[ruprecht]

Yes that's true, but it's not that simple as there's a lot going on with both mechanical and aerodynamic forces. So yes you cyclic forward, the swashplate goes up on the left, the force is applied up at the back via the pitch change links, but then the air applies an upforce to the rotor blade at the back which is translated to up on the right.

It's exacerbated with high torque settings, high speed, asymmetry of lift etc. it could well be stalling the retreating side too - you're holding right cyclic at high speed, which is giving you high AoA on the left, which might stall if the relative airflow suddenly comes more from above. My rotary theory is 25+ years old though, so I could well be barking up the wrong tree. And it may well be unrealistically over-exaggerated, I have no RL experience in the Apache and only limited in a Blackhawk.

Edited March 23, 2022 by ruprecht

[Ruatz]

It’s a bug. Low G maneuvers do not have an effect on the aircraft making an uncommanded roll to the left. Please refer to the other post addressing this earlier today.

 

[S. Low]

I don't know how the stabilator interacts with the real aircraft or how it's modeled in DCS, but if you're flying NOE and go up over a hill then nose down to follow the contour of the hill your aircraft will roll out of control. That's some pretty basic maneuvering. 

 

5 minutes ago, Ruatz said:

It’s a bug. Low G maneuvers do not have an effect on the aircraft making an uncommanded roll to the left. Please refer to the other post addressing this earlier today.

 

Thanks for the heads up.

*Mods please merge my report with the linked post, or lock/delete this one. It was already reported today. Sorry for the double-post and thank you*

Edited March 23, 2022 by S. Low