The Land flight mode allow an automatic landing bellow the current position.
This assumes the Home Location is set correctly and previously a basic PositionHold mode works perfectly using INS13, the preferred fusion algorithm for all GPS assisted modes.
Land feature can be used as a next command after a Return to base.
Set Attitude Estimation Algorithm
To use all the navigation features using GPS,select the GPS navigation (INS13) attitude estimation algorithm
Go into Attitude page > Settings > Attitude Estimation Algorithm, select GPS Navigation INS13, and Save.
Set the flight mode
Go into Input page > Flight Mode Switch Settingsand affect Land to one flight mode position.
How to use
In normal condition the sequence should be like that:
Stabilize your multirotor above the place where you want to land,
Switch to Land flight mode,
Wait automatic descend.
After landing is done, do not switch to another flight mode like Attitude because the Throttle stick should still at middle range.
move the Throttle stick to minimum.
Disarm
Landing settings
Basic: Velocity
Go to System tab, under UAVOBrowser and search for Settings > FlightModeSettings
LandingVelocity is 0.6m/s by default,
Do changes you want and save settings using button.
Advanced: Vertical PIDs
Go to System tab, under UAVOBrowser and search for Settings > VtolPAthFollowerSettings > LandVerticalVelPID
Do the changes you want, default values should work in most cases.