One further point though - how is the heating effect from the Probe Heat element compensated for? Or isn't it?
From the manual for a LARGE Boeing.
TAT Probe.
This probe is a small metal strut and has two temperature-sensitive wire elements,
the resistance of the wire elements changes with temperature. Engine bleed air into
the probe makes a negative pressure which pulls outside air across the sensing
elements.This is at a rate that the heating elements have little effect.This permits
accurate TAT information while the airplane is on the ground and in-flight at low
airspeeds.
