PS. Why can't pprune have a QUOTE button like every other forum?
(A380 FCOM)
The Air Data and Inertial Reference System supplies parameters to the cockpit display (PFD and ND) as well as to other user systems such as
FMS, FADEC, or PRIM.
Each ADIRU is divided in two parts:
The ADR (Air Data Reference) part and the IR (Inertial Reference) part.
The ADR part of the ADIRU provides air data parameters such as:
Total pressure, Static pressure, Altitude, Mach number, Computed airspeed, True airspeed, Static temperature, Total air temperature, Barometric vertical speed,
Angle of attack, Side slip angle.
Vs1g is computed by the PRIMs.
It is a function of:
slats / flaps position, aircraft weight & CG, aircraft altitude, landing gear position
It is also computed by the FMS, for performance prediction, and characteristic speeds displayed on the MFD.