Possible Bug with VNAV profile during descend

  • Dear Jan,

    with regard to VNAV I wanted to report two observations,
    which I also recorded in the video below.

    I put the time marker just before the issue happened...
    If you need more info, you can just jump back. I tried to capture all necessary information.

    Issue with VNAV profile during descend
    ...shown in the LJ45
    1. In general the VNAV profile tends to jump back up in between waypoints, putting you low on profile.
      I guess this may be correct and might have to do with altitude constrains. However:
    2. If this happens in the Learjet 45, VNAV will initiate a climb.
      Is this correct or shouldn't VNAV hold the altitude until the profile comes back down?

    The issue got triggered after passing the waypoint "BETEN".

    This might actually be related to the LNAV issue I had reported a few days ago...
    When I had passed "BETEN", this waypoint jumps back ahead of me in the FMC.

    PS: Another minor thing: If you scroll down when selecting the VS, the value is decreased. Shouldn't that be inverted as usual?

    Edited 3 times, last by Mr_Smith (January 18, 2023 at 3:17 PM).