. Early on in my flying one of the instructors told me to begin the flair when the ground seems to start rushing at you. Worked
I am not sure when to start flaring anymore, I just do it to avoid an accident.
An old rule said a good landing is when you run out of airspeed, altitude, back pressure and vertical speed at the same time. More art that science perhaps.
Any monkey can fly the book, but if he or she does not have the "touch" the "feel" or a bit of luck, it will end badly.
