Attempted two takeoffs today, and the issue is back. Both times attempting to climb out of KDEN 16L. First flight, I left everything default load wise. Second flight, I set the W&B manually with the EFB to the values that my VA loadsheet gave me. Everything looked correct. Both times I verified that the MSFS CG was all the way over - 35%. Both times I double-clicked the button to load the values from EFB to Sim to make sure. Trim was set to the EFB's recommendation. I am using Modern flight model for sure. Conditions were such that icing could occur - but anti-ice was ON for both engines and wing. https://youtu.be/5nMXSUUYFg8 Here is a link to a video of the issue. Interestingly, note 2 other things: Airspeed was not alive in the external view, and the FMS skipped one of my waypoints (BOGEI) and instead went direct STAKR without my input.
Both times, the issue occurred: I ended up flying in a ridiculously nose-high attitude. I was able to climb about 1000 FPM, but with 20 degrees pitch, TOGA thrust, and a headwind I should be able to achieve higher performance than that lol.
I feel like the most likely issue is aggressive icing, invisible visually, that affects the aircraft even when the Anti-Ice systems are on. Tomorrow I will try the same departure with visual-only ice, but tonight it is late and I am honestly sick of it lol. I am hoping that by the video you can see something obvious that I did wrong, because I otherwise LOVE this aircraft and would absolutely hate for it to have hidden, game-breaking bugs that trigger, for example, when I am trying to fly on VATSIM.
Something else interesting that I encountered on another flight today, possibly related: At one point the aircraft would not climb properly by the autopilot at ALL. Set climb SPD 290 KTS and it pitched up violently, targeting around a 5000FPM rate (!). I then tried Vspeed, and that did not take - I would set VS to something reasonable (like 2000fpm), engage VS, and... nothing. Maybe a maximum of about 400 FPM. I know I was accelerating properly as in level flight the aircraft would quickly exceed 300Kts and overspeed at this point while VS mode failed to engage. I have attached a picture of the VS issue.