737 Pre-stall buffet at high altitude. Not at landing config low alt. Why?
During stalling recovery practice in the 737-300 simulator at high altitude (37,000 ft for example) there is very strong buffet preceding stick shaker operation. So strong that it is obviously cannot be mistaken for normal turbulence.
On the other hand when the simulator is set up for a practice approach to the stall recovery on final approach in landing configuration where action is taken at stick shaker, there is no discernable pre-stall buffet.
No doubt there is an obvious answer to why a heavy pre-stall buffet at high altitude; but no buffet in landing configuration at low altitude.
Presumably, something to do with flap and leading edge extension at low altitude that changes stall characteristics - but why is this so?
Does this occur in real life or is it a simulator fidelity problem?