The preliminary SDK associated with the SU10 beta flighting includes new
parameters for the flight model for spoiler lift and drag while in the air,
while the existing spoiler lift and drag variables now pertain to ground
operations (unless the in air spoiler lift and drag parameters are not used).
I’ve been testing how these parameters work using the default A320 and have
had some curious results. I only investigated the drag effect, and to make
sure the lift effect did not interfere in some way, I set the lift affect for
both air and ground spoilers to -0.001. First, I looked at the spoiler drag on
the ground. I set the ground spoiler delta cd to 0.001 and the in air spoiler
delta cd to 0.1. I was surprised to see a Cd spoiler of 0.06109.
delta cd to 0.001 and the ground spoiler delta cd to 0.1. Again, on the
ground, I was surprised to see spoiler cd of 0.00006.
spoiler delta cd set to 0.001 and the ground spoiler delta cd set to 0.1, the
spoiler cd was given as 0.00006.
the flight_model.cfg file resulted in a spoiler cd of 0.06109.
set to 0.14 and the ground spoiler delta cd set to 0.15, the spoiler cd was
given as 0.08552. From these results, it looks like the air spoiler drag is
being used both in the air and on the ground, and that the ground spoiler
delta cd is not being used at all. (Note: I did go back and double-check that
the gear is on ground simvar returned a “true” value for these cases.) It also
appears that the spoiler drag value shown in the drag debug window is always
61% of the delta cd value in the flight_model.cfg file. Why is this? As I
said, I did not check the effects of the ground and air spoiler lift
parameters, but I am concerned that they may also exhibit these issues.