Originally Posted by grity
flying in future "sound and altitude" as backup system.....!
Perhaps the cockpit noise is somewhat sensitive to sideslip and AoA. The AF447 analysis can (will?) use IRS-derived groundspeed together with last known wind speed at cruise FL, and from meteo data at lower altitudes, or alternatively, airspeed derived from Weight and AoA. The principle is shown in
this graphical illustration. The latter method may also be useable as backup system