After flying it few times, I noticed that the IAS and Mach pitch modes can be a little slow and not consistent. For the era of the L1011, this should be solid. I flew DC1030s and planes of the era were solid. The only issues I would see, which still impacts current aircraft, is temperature inversions. This causes the speed to change and leads to the aircraft pitching to attain speed. The aircraft can easily get into porpoising, which gets worst over time. The trick is to hit vert speed and lock into a climb rate. Once the aircraft settles, you can go back to IAS or Mach pitch modes. Once you get into Mach change over in the climb, aircraft can become a little pitchy as there is some variance along the Mach scale leading to the aircraft making large pitch changes. The heavier the aircraft, the better it performs in this regard. Again, the vert speed technique is used to settle the aircraft. Other than that, these pitch modes are very stable and quick to respond. So much so that you start in vert speed and increase it until the engines reach climb power and then engage IAS or Mach pitch modes. This makes the transition to these pitch modes smooth.    

There are additional updates coming that aim to tune this exact behavior, thank you 🙂

Hello,

Still the case as of 1.0.2.

IAS mode is very lazy and in general will be 20KIAS too slow