An improved
system and method are disclosed for indicating the validity of airport
runway visual approach slope indicators on an aircraft display. An aircraft display
system is provided, which includes a
database for storing data about the specific visual approach slope lighting indicator
system being used by each airport of a plurality of airports and any special distance and / or usage limitations associated with each such visual approach slope indicator system, a
processing unit, a position determination unit, and a visual display. As an aircraft approaches an airport, the
processing unit receives the aircraft's current position from the position determination unit, and compares the aircraft's current position data with the distance and / or usage limitation data stored in the
database for the approach slope indicator system being used by that airport. If the
processing unit's comparison of the aircraft's current position data and the airport's distance and / or
usage data indicates that the visual approach slope lighting indicator system is within a valid range, then the processing unit provides a
display format of a simulated airport environment for the airport of interest to the visual display, which includes a symbolic presentation of the airport's visual approach slope lighting indicators associated with the aircraft's current position, along with appropriate colors for the lighting elements being displayed. However, if the processing unit's comparison of the aircraft's current position data and the airport's distance and / or
usage data indicates that the visual approach slope lighting indicator system is not within a valid range, then the processing unit provides a
display format of a simulated airport environment for the airport of interest to the visual display, which includes a symbolic presentation of the airport's visual approach slope lighting indicators with the lighting elements capped, for example, with a red X symbol. Therefore, in this manner, the accuracy, availability and validity of the
lighting system, and the safety of the aircraft's approach and landing are significantly improved.