Welcome to the forum for MobiFlight! Feel free to reach out to the community in case you have questions, issues or just want to share great ideas or details about your latest home cockpit project.
You like MobiFlight? Donate via PayPal and support the MobiFlight development. Thanks!
By VNAV, I mean the VNAV button that appears in Cessna 172 G1000 and other planes.
I also have seen VNAV button in PMDG 737.
VNAV is 'vertical navigation', the same way LNAV is lateral navigation. The LNAV is related to HDG: you can choose to manage horizontal navigation by selecting HDG or by selecting FMC data (LNAV). The same way, regarding vertical navigation, it can be managed in several ways: set a target altitude and select Vertical speed mode, which will climb or descend to the target at selected rate of climb or descent (VSPEED); set a target altitude and select Flight level change mode which will climb or descent to the targer at selected air speed; or by VNAV mode, which will use the data in FMC flight plan.
I am not interested in default A320, because it has many bugs in autopilot.