Opposite torque when adding or reducing thrust ?

[cmbaviator]

I noticed something weird:

 

When i add thrust, the nose pitched down and when i reduce thrust, the nose pitched up, but thats wrong? that's only the case when the engines are above the CoG like a CRJ 1000 or Challenger 650 for example but its not the case of the F1, when adding thrust it should pitche Up and Vice versa

 

Anyone noticed that as well ?

 

FYI: i flew the F1 as a recon plane on tempest server so no ordonnace, no cannon ammo and about 80% of fuel

[Iron Sights]

I tested it yesterday and it seems to me that speed affects the nose up. Faster I go, more down trim, but I have not noticed a change from thrust. I’ll test it again today.

[cmbaviator]

On 11/18/2022 at 9:12 PM, Iron Sights said:

I tested it yesterday and it seems to me that speed affects the nose up. Faster I go, more down trim, but I have not noticed a change from thrust. I’ll test it again today.

Yes indeed but it seems that during thrust changes, it affects the pitch in the opposite. Cqn try to do a video

[Morskoul]

At which speed/Mach & altitude did you notice that?

[cmbaviator]

19 hours ago, Morskoul said:

At which speed/Mach & altitude did you notice that?

 

8K - 10K mach 0.8 - 1.1

[Morskoul]

In transonic and supersonic, trimming versus speed can be inverted due to aerodynamic effects usually known under the name of "Mach Tuck". I cannot say if the behavior is representative of the real Mirage F1, but it can be explained by the center of lift moving backward on the wing and/or a decreased efficiency of the horizontal stabilizer.

It is very noticeable on the Mirage F1, I agree. I think the worst is between M0.9 and M1.2.

I guess that if this is too far from the aircraft the flight model will be adjusted.