747 Autopilot - VNAV not working / VNAV not taking waypoint's altitudes into account?

Dear all,

I am not sure if this is a bug or an issue on my side.
I am flying the 747 provided with the standard version and I am
on the latest update but I don’t manage to get the VNAV to work properly.

The main issue for me is that the VNAV does not follow the altitudes programmed in my flight plan.
It seems that it ascends directly to the cruise altitude and then does not care anymore about the altitudes associated to the waypoints. If I change the cruise altitude it changes the altitude. But any altitude associated to the waypoints other than the cruise altitude is ignored.

I think I do everything right. The LNAV navigation is working fine. The flight computer is programmed correctly. When I manually descend to around 1500 feet and activate the LOC / APP then the 747 is approaching correctly, also descending works then. But I would expect the VNAV to also follow the waypoint’s altitudes correctly even when I am not in LOC or APP mode.

Is this a bug? Can someone give me a hint what I might do wrong?

Regards, Torben

Pretty sure it’s a bug, just for the fact I’ve had a lot of trippy things happen with the A320 and 787 A/P.

Just out of curiosity with the 747, when you first load in did you get a voices bug.

Literally uncovered the battery switch and had what sounded like passengers talking but couldn’t make out what they are saying, first time using the 747 so just curious if it’s a bug or something I missing that you might know about.

Hi Gandolf,

no - did not realize that bug you mentioned.

Anyone else here where ‘pure’ following the waypoints altitude worked in VNAV?
(Without engaging LOC/APP).

Is there an official statement from MS somewhere what’s implemented and what not?

Regards, Torben

Hi,

is really no one using the VNAV for waypoints?
I found a tutorial here where VNAV is also described how it should work. No mention of this feature not being implemented?
Is no one using it or is no one having my issue?

Regards, Torben

Those voices you mention are usually noticeable when you switch to one of the cabin window views (drone mode → fixed camera → external 16/17). Probably in your case it was triggered in the wrong moment.

By the way, I’m also experiencing many bugs with 747. I was recently flying over New Zeland, while climbing fo FL300 in LNAV/FLCH mode and crossing the mainland I experienced crazy climb rates of 13000 ft/min that were followed by steep dives. Ultimately I had to take control myself until I reached the sea.

Breath-taking landscapes, realistic clouds… And then everything gets spoiled by these bugs. It’s disappointing, but I’m sure the team is working hard to get them fixed.

I didn’t know the default aircraft had VNAV at all? I don’t fly default aircraft but i think VNAV isn’t supported.

Hi @torbenlive!

I’ve closed this topic because as others have mentioned VNAV isn’t yet implemented in the default aircraft, so it’s not a bug as such with the current systems.

There’s a wishlist item about prioritising VNAV systems, so you may want to vote/contribute to that thread.

Thanks!