How to set the parameters to enable the fixed wing to achieve the best landing effect?Thanks!

My parameter settings:

The landing of a fixed wing sometimes falls early and sometimes falls late.The flare height of the reminder is 5.4m, but the actual execution of the flare action is less than 5.4m, and it is likely to be 2.5m.
I have several parameters that I have not understood.parameters:
LAND_FLAP_PERCNT, TECS_LAND_TCONST
I hope I can get everyone’s help!Thanks!

Does the wind affect the landing effect?

Yes the wind affects landing , you should land against the wind.

Actually the flare is based on LAND_FLARE_SEC , time and not the height.

Yes, I agree with you.LAND_FLARE_SEC*sink_rate = flare_height,The sinking speed of the fixed wing is different at each landing.