altitudeAmsl property
This altitude measure is strictly above mean sea level and might be non-monotonic (it might reset on events like GPS lock or when a new QNH value is set). It should be the altitude to which global altitude waypoints are compared to. Note that it is not the GPS altitude, however, most GPS modules already output MSL by default and not the WGS84 altitude.
MAVLink type: float
units: m
altitude_amsl
Implementation
final float altitudeAmsl;