|Quoting HAWK21M (Reply 4):|
An Unbalanced Flyweight attached to the Control Column receives current from an Angle of Attack sensor,at a high angle
That is not correct. As I stated in my earlier post, the AoA Transmitter looks like a blade or conical post on the side of the nose and is free to rotate, typically through an arc of about 30 degrees. What I should have added is that the Transmitter is positioned by the slipstream, hence it's angle relative to the fuselage is determined by the aircraft's wing's angle relative to the airflow (AoA). The blade or probe is connected to a potentiometer inside a case ,which also is often filled with a damping fluid so that the probe won't 'flop around', for want of a better term. There is also a heating element for ice protection.
Where HAWK21M is incorrect is in saying that the current goes from the AoA sensor to the flyweight. The potentiometer receives a fixed voltage from the Stall Computer and sends a different voltage back, which is proportional to the AoA. The computer determines whether the aircraft's wing is geting close to the stalling Angle of Attack (which is the same for all aircraft, regardless of size, shape, power or airfoil design), about 16 degrees for a wing in 'clean' configuration. The computer takes inputs for gear and flap position because the stalling AoA changes when the wing is 'dirty'. The computer will then send a voltage to turn the motor, which as I and other people have noted, has an eccentric or unbalanced flyweight attached to the end of it which makes it vibrate. The flyweight itself is just a bit of metal and receives no current.
In the LH
photo below you can see two silver things above the crew seats on each control column. These are a pair of hose clamps such as you may find on the radiator hose on your car and they are holding the stick shaker motors on the front side of the control columns. On the very right of the RH
photo, in the middle you can see part of a circle, this is the top of the shaker motor on the front of the RH
control column. Unfortunately the crewmember's leg means that there is no contrast to see the black-painted motor in any detail. In the third photo you can see the AoA Transmitter blade above the Lufthansa logo.
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Photo © Bruno Althaus
Monty Python's Flying Circus has nothing to do with aviation, except perhaps for Management personnel.