Systems and methods for generating and verifying altitude data

A system for determining the validity of altitude data, such system comprising:

• a source of radar-based aircraft altitude data;
• a source of navigation data;
• and
• a first processor configured to
• receive first altitude data representative of a first measurement of aircraft altitude from the source of radar-based altitude data other than a radar altimeter system, where
• the first measurement of aircraft altitude is a measurement of vertical distance between the aircraft and a conventional, fixed reference datum other than an underlying ground surface,
• receive second altitude data representative of a second measurement of aircraft altitude from the source of navigation data, where
• the second measurement of aircraft altitude is a measurement of vertical distance between the aircraft and a conventional, fixed reference datum other than an underlying ground surface,
• determine the validity of the second altitude data by comparing the first altitude data with the second altitude data, and
• generate validity advisory data responsive to the validity determination, whereby
• the validity advisory data is representative of validity information.

A method for generating altitude data, where such method is performed by an aircraft avionics system processor, such method comprising:

• receiving reflection point data corresponding to a reflection point from an aircraft radar system other than a radar altimeter system;
• receiving reference point data representative of the fixed elevation of a fixed surface reference point from a source of reference point data, where
• the fixed elevation of the fixed surface reference point is a measurement of vertical distance between the surface and a conventional, fixed reference datum;
• and
• generating first altitude data based upon the reflection point data and reference point data, where
• the first altitude data is representative of a first measurement of aircraft altitude, and
• the first measurement of aircraft altitude is a measurement of vertical distance between the aircraft and a conventional, fixed reference datum other than an underlying ground surface.

A method for determining the validity of altitude data, where such method is performed by an aircraft avionics system processor, such method comprising:

• receiving first altitude data representative of a first measurement of aircraft altitude from a source of radar-based aircraft altitude data other than a radar altimeter system, where
• the first measurement of aircraft altitude is a measurement of vertical distance between the aircraft and a conventional, fixed reference datum other than an underlying ground surface;
• receiving second altitude data representative of a second measurement of aircraft altitude from a source of navigation data, where
• the second measurement of aircraft altitude is a measurement of vertical distance between the aircraft and a conventional, fixed reference datum other than an underlying ground surface;
• determining the validity of the second altitude data by comparing the first altitude data with the second altitude data;
• and
• generating validity advisory data responsive to the validity determination, whereby
• the validity advisory data is representative of validity information.