MOD 202164 (A330)
MOD 153528 (A320)
The FPV is based on the FPA.
When ADR data is not available the baro-inertial parameter (Vzbi) is missing to calculate the 'classic' FPA. (
FPA = arc tan(Vzbi/GS)
After the mod, if the baro-inertial is not available, this parameter is replaced by GPIRS (a mix of Inertial and GPS pos data)
This FPA is called the hybrid FPA.
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