Originally Posted by
itsnotthatbloodyhard
Sorry, this is not true. The A330/A340 FCOM has procedures for Unreliable Speed Indication, IAS Disagree, and All ADR Off - and NOWHERE does it make any mention of groundspeed. Nor does the FCTM.
I see this reply from a " BUS" pilot - you say there is no reference to GS and he says there is??
Would be good to know since I cannot imaging different Airbuss having different procedures??
Thanks for looking into it. All helps
Y
A bunch of AFCS systems revert to GS on approach in case of turbulence, even the bus. It's a fine reference for a minimum speed and the maths for wind correction isn't taxing. If you have nothing else then referring to GPS speed is an excellent idea and I've read it in more than one FCOM.
Here is what is says in my current QRH unreliable airspeed after pitch power initial items:
Quote:
d) Check all available data sources, including:
• FMS, POS - GNSS for ground speed,
• FMS, POS - GNSS INFORMATION for GNSS ALT (if required),