I am a simple pilot that agree with Chris Scott affirmation. On the CRJ with flux valves the unusual was to see same wind vector on both ND, and I have flown many of CRJ200 from the first week of its life. The B757 is pretty accuracy, but it is not unusual to see variations from both ND readouts. Same on A340, especially on long haul flights with long periods from alignment. As Scott has very well stated a little variation on the heading may produce a huge deviation on the wind vector. Anyway, strong winds are more reliable because the wind vector gets more relevance on the triangle of velocities and produces not such huge variations. Graphically if within the triangle of v, we decompounds the obtained wind vector in one for real wind and one for error, as the real wind grows and the error remains the same the resulting vector trends to the bigger vector.
At the end the more important wind is what the simple controller reads from the anemometer that it will be the same that you will encounter on the simple touchdown and the simple deceleration roll despite of what your ND is false showing.
Simple flights to all.
Last edited by ppppilot; 28th March 2008 at 11:46.