Roger Roger
Bottom of the list
Yes, in UNS speak it looks likeAre you talking about putting a point in front of a point; i.e. descend to reach FLXXX 10 miles before WAYPT? Is that what you’re referring to?
If so, there’s probably a point in between you and that 10 miles before the fix.
FIXXX -5 6000 on the vnav page for 6000’ at 5 miles prior to FIXXX. But sometimes it won’t take a negative number in the offset. In the case I was having trouble with there was no other fix between us and the one I wanted to vnav to. It would take 0 offset and a positive offset (past the fix) but not prior to. Usually it works just fine but some scenarios it just won’t do it.
I know some FMSs will create a new waypoint (labeled something like XPD001 or something) for the VNAV offset that then appears in the flight plan, as far as I can tell that’s not the way the UNS handles it (or if it is, it hides that logic away from the pilots and it doesn’t show in the flight plan).
I’m suspecting now that it has something to do with selecting an earlier fix than what auto populates on the vnav page. Say for example your flight plan is currently -D-> FIXXX FIXXY FIXXZ, for some reason that I don’t know when you go to the vnav page often the active vnav fix will default to FIXXY or FIXXZ. When you change it to FIXXX, seems to be when the offset gets jammed up.