Quote:
Originally Posted by BOAC
Apologies if I have missed this in the welter
of OOZLUM bird flocking, but do we know if AB have now addressed the logic for
the stall warning 'inhibit' below 60kts?
Such particularity of the stall warning is not in the FCOM, therefore any
change made to it would be most probably transparent to us.
But A33Zab
would be the guy to answer the question as he seems more aware on
those things.
Actually it is not - stall warning 'inhibit' below 60 kts - but an AoA NCD status (No Calculated Data) below 60 kts.
IMO this was already resolved with BUSS option:
Flight Safety #05 dd december 2007:
"In order to decrease the crew workload in case of
unreliable speed, Airbus has developed the Back-
Up Speed Scale (BUSS) that replaces the pitch
and thrust tables. The BUSS is optional on
A320/A330/A340. It is basic on A380, being part
of the ADR Monitoring functions.
This indication is based on angle of attack(AOA)
sensor information, and is therefore not affected
by erroneous pressure measurements.
The BUSS comes with a new ADIRU standard
(among other new system standards), where the
AOA information is provided through the IRs and
not through the ADRs. This enables selecting all
ADRs off without loosing the Stall Warning
Protection.
......"
Not with a direct reference to this 60 kt value but from this information AoA sensing is not thru ADR and therefore not affected by any airspeed.
(apart from stall warning reference tables which depends on Mach in Alternate/Direct and solely on S/F setting during BUSS operation)
I am not aware of other system modifications e.g. when an airliner will not opt. for the BUSS (wouldn't that be stupid?)
Latest system enhancement to the BUSS is that FPV is available when BUSS is active.