Strange Issue with VNAV during Climb (B777)

  • Hi Jan,


    it's me again. I discovered a strange issue with VNAV during climb phase:


    Shortly after take off the T/D moves towards

    the position of my plane, putting itself ahead of T/C.


    This causes VNAV PTH to engage during climb:


    B777 | VNAV Issue during Climb
    VNAV PTH engages during climb due to T/D moving ahead T/C
    youtu.be


    This time my route was:



    After the T/D had passed me - I had just taken off -
    I could reengage VNAV SPD.

    It almost seems as if there was an additional false T/D...


    Greetings!


    Update: It now makes sense to me that VNAV PTH engages due to the ALT constraint
    (4000A 7000B). Is it correct though that the T/D moves through me?