Patent ID: 8374776
Filing Date: 2013-02-12
Classification: G08G

Abstract:
1. A method for indicating a relative altitude of a vehicle, the method comprising: obtaining, from at least one navigation instrument, a current geographic position and a current altitude of the vehicle; defining, by a processor, one or more geographic areas surrounding the current geographic position, the one or more geographic areas defining a plurality of contiguous sectors within an annulus having a center approximately at the current geographic position of the vehicle; determining, by the processor, a minimum safe altitude (MSA) for each geographic area of the one or more geographic areas based at least in part on a minimum clearance height and at least one of the following: a maximum terrain elevation within the geographic area, and a maximum obstruction elevation within the geographic area; determining, by the processor, a relative altitude for each geographic area of the one or more geographic areas, the relative altitude representing the current altitude of the vehicle relative to the MSA for the geographic area; and displaying, via a presentation device, a relative altitude indicator for each geographic area of the one or more geographic areas based at least in part on the corresponding relative altitude, wherein a relative altitude indicator corresponding to an MSA below the current altitude is graphically distinguished from a relative altitude indicator corresponding to an MSA above the current altitude.