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When an aircraft is in a banked turn the accelerometer will measure gravity plus this centripetal
acceleration which will result in a measurement vector that acts perpendicular to the wings of the aircraft
as shown in the above figure. This will result in the AHRS estimating a roll angle of zero while the aircraft
is in fact in a banked turn and thus has a significant actual roll angle relative to the horizon.
If the AHRS however can obtain some knowledge of this actual motion relative to the fixed Earth then it
is possible for it to subtract out the effect of the centripetal acceleration, resulting in an accurate estimate
of attitude. By providing the AHRS with the known velocity or airspeed it is possible for the AHRS to
estimate the centripetal acceleration term based upon this velocity and the known body angular rates.
Figure 2 - AHRS with Velocity Compensation
The above figure accurately depicts quality of attitude solution provided by three separate types of
attitude estimators while operating in a coordinated turn. The flight display on the far left represents the
