Originally Posted by
AC-DC
So do you say that a lighter aircraft can't fly at the same AoA as the heavier one? The stall warner (the small flap at the leading adge) does not know how heavy the aircraft is, all its know is AoA hence a relative airflow. The warner doesn't care if you fly at 200kts or 20kts. If the AoA is to high the realtive airflow will push the warner's flap up which will close a switch that activates a buzzer or a warning light.
No. But at a fixed speed - which was the original question - the heavier aircraft will be at a higher AoA and therefore a stall warner may go off for the heavier aircraft but not for the lighter, if the setting is between the two actual AoAs.
It's true that the stall warning system has no direct weight input, but because it looks at AoA, and AoA is a function of both weight and speed, at a given speed one can say that the stall warning system does take some account of weight - hence I said "know" in quotes.