Altitude

Ardupilot reports two altitude types - AMSL (Above Mean Sea Level) and AHL (Above Home Location). UgCS is using only the reported AMSL altitude. In previous versions of altitude, AHL from Adrupilot was reported as RAW altitude. It was decided not to show altitude AHL as RAW because it would be inconsistent with other supported autopilots. Altitude AHL will be added in future versions of UgCS.

Current altitude AGL (Above Ground Level) is calculated as:

Vehicle altitude AGL = Reported vehicle altitude AMSL - Terrain elevation AMSL at vehicle location