Originally Posted by
Turbo Encabulator
Here's one. How come VNAV routinely starts down at TOD and suddenly decides that it's 2000 feet low on path and reverts to VNAV SPD? I"m like you're the one who calculated the TOD point
I know VNAV has it's quirks but FWIW I had few thousand hours on the T7 and can't say I ever saw what you describe happen as a matter of routine.
Given old age I can only guess I'd be suspecting maybe winds (the point Uplinker made)/ or, and I'm clutching at straws here - programmed descent speed vs. programmed cruise speed - does it routinely happen if you transition from Econ cruise to Econ descent?