Avionics system and method for providing altitude alerts during final landing approach

• US 6,980,892 B1
• Filed: 11/18/2003
• Issued: 12/27/2005
• Est. Priority Date: 11/18/2003
• Status: Active Grant

• Current Assignee: Garmin International, Inc. (Garmin Limited)
• Original Assignee: Garmin International, Inc. (Garmin Limited)
• Inventors: Chen, Susan S., Barber, Clayton E.
• Primary Examiner(s): Zanelli, Michael J.
• Application Number:
  US10/716,735
• Time in Patent Office: 770 Days
• Field of Search: 701/16, 701/18, 701/4, 701/8, 701/9, 340/970, 340/963
• US Class Current: 701/9
• CPC Class Codes: G01C 21/005 with correlation of navigation data from several sources, e.g. map or contour matching G01C21/30 takes precedence
• CPC Class Codes: G01C 23/00 Combined instruments indicating more than one navigational value, e.g. for aircraft; Combined measuring devices for measuring two or more variables of movement, e.g. distance, speed or acceleration
• CPC Class Codes: G01S 19/15 Aircraft landing systems
• CPC Class Codes: G05D 1/0676 specially adapted for landing
• CPC Class Codes: G08G 5/025 Navigation or guidance aids radar or analogous systems specially adapted for landing purposes G01S13/913

Abstract

An avionics system and method is employed for alerting pilots of low premature descent during final landing approach. The method involves determining Final Approach Flight Safety Altitudes for a plurality of runways, identifying which runway an aircraft is likely to land on, and alerting the pilot if the aircraft altitude is lower than the final approach flight safety altitude. The method takes into account terrain information, airport and runway information, and aircraft reference data to make its determination. Particular embodiments reference the Final Approach Fix, one or more step down fix values, the Minimum Descent Altitude and the Missed Approach Point in calculating the Final Approach Flight Safety Altitudes. The system and method have particular utility with a Terrain Awareness and Warning System (“TAWS”) and display in an aircraft.

Claims

1. A method of providing a Premature Descent Alert for an aircraft during a final landing approach, the method comprising:

determining a plurality of Final Approach Flight Safety Altitudes for each of a plurality of runways;

storing the determined Final Approach Flight Safety Altitudes in association with each corresponding runway upon a media readable by a Terrain Awareness and Warning System (“

TAWS”

);

identifying upon which runway an aircraft will land; and

generating a Premature Descent Alert during the final landing approach for the aircraft to the runway by reference to the determined Final Approach Flight Safety Altitudes for the identified runway, wherein the Final Approach Flight Safety Altitudes further comprise Final Approach Flight Safety Altitudes corresponding to each of at least two approaches to at least one of the runways.

2. A method of providing a Premature Descent Alert for an aircraft during a final landing approach, the method comprising:

determining a plurality of Final Approach Flight Safety Altitudes for each of a plurality of runways;

storing the determined Final Approach Flight Safety Altitudes in association with each corresponding runaway upon a media readable by a Terrain Awareness and Warning System (“

TAWS”

);

identifying upon which runway an aircraft will land; and

generating a Premature Descent Alert during the final landing approach for the aircraft to the runway by reference to the determined Final Approach Flight Safety Altitudes for the identified runway, wherein the Final Approach Flight Safety Altitudes corresponding to each of the runways correspond to determined distances from each runway, the final approach safety altitudes representing step-down points on a flight safety altitude for reference by an aircraft landing on the runway.

3. The method of claim 2, wherein the Final Approach Flight Safety Altitudes are between a Final Approach Fix point for the runway and a runway.

4. A method of providing a Premature Descent Alert for an aircraft during a final landing approach, the method comprising:

determining a plurality of Final Approach Flight Safety Altitudes for each of a plurality of runways;

storing the determined Final Approach Flight Safety Altitudes in association with each corresponding runway upon a media readable by a Terrain Awareness and Warning System (“

TAWS”

);

identifying upon which runaway aircraft will land; and

generating a Premature Descent Alert during the final landing approach for the aircraft to the runway by reference to the determined Final Approach Flight Safety Altitudes for the identified runway, wherein at least a portion of the plurality of Final Approach Flight Safety Altitudes are determined during the aircraft'"'"'s flight in which the Final Approach Safety Altitudes are referenced.

5. A method of providing a Premature Descent Alert for an aircraft during a final landing approach, the method comprising:

determining a plurality of Final Approach Flight Safety Altitudes for each of a plurality of runways;

storing the determined Final Approach Flight Safety Altitudes in association with each corresponding runway upon a media readable by a Terrain Awareness and Warning System (“

TAWS”

);

identifying upon which runway an aircraft will land; and

generating a Premature Descent Alert during the final landing approach for the aircraft to the runaway by reference to the determined Final Approach Flight Safety Altitudes for the identified runway, wherein at least a portion of the Final Approach Flight Safety Altitudes are each determined such that they lie upon a curve that approximates a vertical flight path.

6. The method of claim 5, wherein at least a portion of the curve is a quadratic curve.

7. The method of claim 5, wherein the portion lying upon a curve that approximates a vertical flight path is within a segment nearest the runway.

8. The method of claim 5, wherein the curve approximates a dive and drive flight path.

9. A method of providing a Premature Descent Alert for an aircraft during a final landing approach, the method comprising:

determining a plurality of Final Approach Flight Safety Altitudes for each of a plurality of runways;

storing the determined Final Approach Flight Safety Altitudes in association with each corresponding runway upon a media readable by a Terrain Awareness and Warning System (“

TAWS”

);

identifying upon which runway an aircraft will land; and

generating a Premature Descent Alert during the final landing approach for the aircraft to the runway by reference to the determined Final Approach Flight Safety Altitudes for the identified runway, wherein a portion of the plurality of Final Approach Flight Safety Altitudes are determined during the aircraft'"'"'s flight in which the Final Approach Safety Altitudes are referenced and are determined such that they lie upon a curve that approximates a vertical flight path.

10. The method of claim 9, wherein the portion of Final Approach Flight Safety Altitudes determined such that they lie upon a curve that approximates a vertical flight path is within a segment nearest the runway.

11. A Terrain Awareness and Warning System (TAWS) for an aircraft, the TAWS comprising:

at least one information database configured to store elevation and position information for a terrain region and a plurality of Final Approach Flight Safety Altitude values specific to each of a plurality of runways;

a look-ahead warning generator configured to receive indications of terrain clearance alerts and communicate the indications by at least one of a visual display and an aural alert; and

a processor coupled to the information database and the look-ahead warning generator, the processor configured to identify a runway on which the aircraft will land, and employ the Final Approach Flight Safety Altitude values for the identified runway to cause the look-ahead warning generator to generate an alert if the aircraft flies below the Final Approach Flight Safety Altitude values for the identified runway when the aircraft is in its final approach to the runway, wherein the Final Approach Flight Safety Altitudes specific to each of the plurality of runways further comprise Final Approach Flight Safety Altitudes specific to each of at least two approaches to at least one of the runways.

12. A Terrain Awareness and Warning System (TAWS) for an aircraft, the TAWS comprising:

at least one information database configured to store elevation and position information for a terrain region and a plurality of Final Approach Flight Safety Altitude values specific to each of a plurality of runways;

a look-ahead warning generator configured to receive indications of terrain clearance alerts and communicate the indications by at least one of a visual display and an aural alert; and

a processor coupled to the information database and the look-ahead warning generator, the processor configured to identify a runway on which the aircraft will land, and employ the Final Approach Flight Safety Altitude values for the identified runway to cause the look-ahead warning generator to generate an alert if the aircraft flies below the Final Approach Flight Safety Altitude values for the identified runway when the aircraft is in its final approach to the runway, wherein the Final Approach Flight Safety Altitudes specific to each of the runways correspond to predetermined distances from each runway, the final approach safety altitudes representing step-down points of a flight safety altitude for reference by an aircraft landing on the runway.

13. The TAWS of claim 12, wherein the Final Approach Flight Safety Altitudes are between a Final Approach Fix point for the runway and a runway.

14. A Terrain Awareness and Warning System (TAWS) for an aircraft, the TAWS comprising:

at least one information database configured to store elevation and position information for a terrain region and a plurality of Final Approach Flight Safety Altitude values specific to each of a plurality of runways;

a look-ahead warning generator configured to receive indications of terrain clearance alerts and communicate the indications by at least one of a visual display and an aural alert; and

a processor coupled to the information database and the look-ahead warning generator, the processor configured to identify a runway on which the aircraft will land, and employ the Final Approach Flight Safety Altitude values for the identified runway to cause the look-ahead warning generator to generate an alert if the aircraft flies below the Final Approach Flight Safety Altitude values for the identified runway when the aircraft is in its final approach to the runway, wherein at least a portion of the Final Approach Flight Safety Altitudes are each determined such that they lie upon a curve that approximates a vertical flight path.

15. The TAWS of claim 14, wherein the portion of the Final Approach Flight Safety Altitudes determined such that they lie upon a curve that approximates a vertical flight path is determined during the flight in which the Final Approach Flight Safety Altitudes are referenced.

16. The TAWS of claim 14, wherein at least a portion of the curve is a quadratic curve.

17. The TAWS of claim 14, wherein the portion lying upon a curve that approximates a vertical flight path is within a segment nearest the runway.

18. The TAWS of claim 14, wherein the curve approximates a dive and drive flight path of the aircraft.