Originally Posted by
BuzzBox
I fly Airbus these days and it's been a while since I flew the B777, but I don't remember the B777 VNAV behaving as you described. As I recall, the MCP speed window would close (if open) when the FMC transitions to 'on approach'. The speed window could then be opened and the VNAV would stay in VNAV PTH instead of changing to VNAV SPD. I think the B787 is similar. There was a discussion about the B777 case many moons ago:
LNAV/VNAV Approach.
My mistake, it had been a long night...yes, agreed- speed window can be opened when “on approach”, you can then fly the approach in VNAV PTH controlling speed with the MCP.