Originally Posted by
RexBanner
Nah they can definitely see what speed you have selected on the MCP. Hence why flying an approach with managed speed into Heathrow (as long as S and F speeds comply with the speed control given) confuses the hell out of them and often they’ll ask you to confirm your speed.
Then allow me to ask you the same question that I asked the previous poster (who subsequently decided that selected speed wasn't displayed, after all):
Originally Posted by
DaveReidUK
Which BDS are you getting selected speed from ?
I can't find anything in the Mode S/EHS spec that has provision for MCP selected speed. While selected altitude has obvious benefits in providing potential early warning of a possible level bust, I'm struggling to see similar benefits for an approach controller who already has access to your IAS and, as noted above, will likely ask you what you're doing if you appear to be ignoring a speed instruction.
Can anybody provide a definitive reference to any recent changes to the Mode S/EHS spec that make this provision?