I have to agree. VNAV is unreliable. Sometimes it seem to work correctly, sometimes it doesn ‘t.
TOD calculations are often not correct and the aircraft will not match hard altitude constraints by many hundreds feet.
I confirm the fact that it does not follow a smooth path: it seem to follow sort of “ladder” profile (slow descent before a waypoint and then abrupt diving after passing it). Tried several approaches at different 3d party and stock airports: same results.
Furthermore I also observed a “lazy” LNAV behaviour: it struggles to follow sharp turns ,also at low speeds, and sometimes it does not catch the waypoint, wich is therefore skipped: in this case the only possible solution is to manually insert a DTO to the next waypoint, otherwise FMC will remain stuck to the previous one.
I know this is only 20 bucks but nevertheless i think that an “expert series” aircraft should behave better than this……by now it seem to me nothing more than an advanced beta.
Hope that Asobo will continue to improve this!
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