Hi HazelNuts39,
Please see John T's explanation
http://www.pprune.org/tech-log/48445...areness-2.html.
If the stall speed is calculated as being X kts and superimposed on the speed display accordingly, but due to iced over pitots at 250kts, your IAS only shows 60 kts, then your stall speed will be off the scale at X kts. All you'll know is that you think you are below the stall speed on the IAS read out - even though you may still be at 250kts. The BUSS system (when displayed) is independent of pitots.
As far as I know, BUSS is only displayed after all 3 ADRs are turned off manually.
Hi A33Zab.
Thanks for diagram of 787 yoke system. It's definitely a lot more complicated, heavy and costly than the Airbus side sticks - but at least the control surface displacement feed back loop to both pilots is complete.