VNAV, why doesn't it work?

I cannot get it to work no matter what I do. I assume its only for approach but isn’t that what the APPR is for?

p.s my entire flight plan has indicating altitudes per fix.

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Could you provide a replay file where VNAV isn’t working for you?

I recommend using

I’m actually mid-flight rn.

VNAV Tutorial This tutorial by Tyler can show you how to use VNAV.

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Hi, can you please say at which stage of the flight it wasn’t working and did you get any warning messages after trying to activate it?

The VNAV helps you during the descent, as it calculates the TOD automatically, and sets the correct VS based on your altitude and speed. Maybe you’re too far away from the TOD.

Never engage the VNAV before one minute of the TOD, this is to avoid violations if you are not controlling the flight.

For more information about VNAV and how to use it, take a look at the user guide.

Right now, im about 50NM from my destination. which I imagine is exactly where decent should start anyway.

It depends on parameters like your ground speed and altitude to loose. If you go to the VNAV button, does it say [number] NM bellow the word VNAV?

Yes, it said 1NM. I’m not sure why it didn’t work before. Maybe, I really was just too far away.

If it said 1NM, it means that the system thinks you are still 1 NM away from the point at which you should start descending. I too sometimes catch myself wondering whether I activated VNAV or not, only to then find out that I haven’t yet reached the point where it starts to descend, we are all a bit paranoid about it sometimes