Is a normal landing a controlled stall?

[Blackshift]

A and C,

Buffet, stall warner, low speed, unusually high aoa are all warnings of an impending or incipient stall - if the flare was too high there would undoubtedly be a perceptible buffet before the greatest loss of lift would be experienced. However, the buffet is surely at that stage of the stall-break where the airflow begins to seperate from the upper-surface and the lift threatens to decrease even more rapidly than before.

It has nevertheless decreased initially only slightly just at the back end of the lift/aoa curve in the case of a well executed landing, just enough to allow the mainwheels to settle on the runway - otherwise we would still be up there two feet above the runway.

In this case the stall simply doesn't have time to develop fully, due to the wheels taking the weight at almost the instant the aircraft reaches the back end of the lift/aoa curve, which is after all a curve, thus indicating a progressive rather than an instant occurance as the aoa is altered in the flare.

I suspect that we are not entirely in disagreement here, because I have already suggested that this is effectively reduced to an incipient more than a developed stall when done properly.

This is of course a matter of degree, rather than an absolute distinction:-

At the desirable end of the scale "greaser" is attained towards (but crucially just beyond - otherwise no descent!) the incipient side of the stall. I fully agree that ground effect might be of assistance in this process, especially in low wing a/c (the down side being that low wing a/c also have a greater tendency to "float" when the approach speed is too high), but that does not stop this from being a stall - it just becomes an even more progressive stall due to the delay in the breakdown of airflow above the wing, hence no buffet.

And at the less-than-desirable end of the scale, a collapsed undercarriage, or worse, would result from a fully developed stall with all the associated buffet and subsequent downwards acceleration you might expect as much of the lift is dumped from the wings after a continued attempt to flare too high above the runway.