I just tried stalling while in a slip. With full right rudder, and just enough left aileron to keep wings level I applied about fifteen degrees of pitch until I ran out of airspeed. The left wing was first to drop and with the debug forces enabled I could see that the left wing had shorter lift vectors towards the tip of the wing before going into he stall. As I played around with the amount of left elevator while in that slip I saw that the left wing lift vector dropped as I applied more left elevator, this is something you also see in x-plane with the same visualization enabled but there the behavior is that the wing farthest from the relative wind drops first.
What I think is going on here with MSFS is that the changing angle of attack of the wing along the aileron is not sufficiently taken into account. As you deflect an aileron down you change the chord line which affects your angel of attack since the AoA is measured as the angle between the relative wind and the chord line. In the case where you are in a slip with full right rudder you are rolling left with the yoke, this causes the left wing to raise its aileron, this decreases the AoA, and on the right wing you drop the right aileron to lift that wing and in doing so increase the AoA. So because of the difference in AoA between the wings, plus any wind blanking that may happen as a result of the fuselage blocking some wind from the right wing the left wing should stall first. Hopefully that made sense.
The question that shakes out of all of this for me is:
- How does MSFS compute AoA for the wings?
- Does MSFS take into account the effects of control surface deflections, especially ailerons on the chord line of each surface (wing/v-stab/h-stab)?
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