Meteorological data selection along an aircraft trajectory
A method of selecting weather data for use in at least one of a flight management system (FMS) of an aircraft and a ground station includes selecting a reduced set of weather data points to send to the FMS and taking into account a trajectory of the aircraft when determining what data points to include in the reduced set.
1. A method of selecting weather data for use in at least one of a flight management system (FMS) of an aircraft and a ground station comprising:
generating a reference aircraft trajectory using a reference data set comprising data points from a weather database along the trajectory, where the data points comprise a spatial position with associated weather data;
generating an approximate aircraft trajectory using a reduced data set comprising fewer data points than the reference data set;
comparing the reference aircraft trajectory to the approximate aircraft trajectory;
determining at least one difference between the reference aircraft trajectory and the approximate aircraft trajectory based on the comparison;
selecting a data point from the weather database corresponding to the determined at least one difference where the selected data point is not in the reduced data set, adding the selected data point to the reduced data set; and
providing to the at least one of the FMS and the ground station the associated weather data of the selected data point.
2. The method of claim 1 wherein the reduced data set comprises a number of data points not greater than a number of data points that can be inputted into the at least one of the FMS and the ground station.
3. The method of claim 1 wherein the reduced data set comprises at least some of the data points in the reference data set.
4. The method of claim 1 wherein the determining at least one difference comprises determining multiple differences and the selecting a data point comprises selecting a data point for each of the multiple differences.
5. The method of claim 1 wherein the providing to the at least one of the FMS and the ground station the associated weather data of the selected data point comprises providing the selected data point as at least one of an enroute waypoint, pseudo waypoint or altitude to the at least one of the FMS and the ground station.
6. The method of claim 1 wherein the reference aircraft trajectory comprises at least one of a climb phase, a cruise phase, and a descent phase.
7. The method of claim 1 wherein the determining at least one difference comprises determining the points on the reference aircraft trajectory and the approximate aircraft trajectory where the difference exceeds a difference threshold.
8. A method of selecting weather data for use in at least one of a flight management system (FMS) of an aircraft and a ground station comprising:
a) generating a reference aircraft trajectory using a reference data set comprising data points from a weather database along the trajectory, where the data points comprise a spatial position with associated weather data;
b) generating an approximate aircraft trajectory using a reduced data set comprising fewer data points than the reference data set;
c) comparing the reference aircraft trajectory to the approximate aircraft trajectory;
d) determining at least one difference between the reference aircraft trajectory and the approximate aircraft trajectory based on the comparison;
e) selecting a data point from the weather database corresponding to the determined at least one difference where the selected data point is not in the reduced data set;
f) replacing a data point in the reduced data set with the selected data point;
g) repeating steps b-f until the determined at least one difference satisfies a predetermined error threshold; and
h) providing to the flight management system the weather data from at least some of the data points in the reduced data set.
9. The method of claim 8 wherein the reduced data set comprises a number of data points not greater than a number of data points that can be inputted into the at least one of the FMS and the ground station.
10. The method of claim 8 wherein the reduced data set comprises at least some of the data points in the reference data set.
11. The method of claim 8 wherein the determining at least one difference comprises determining multiple differences and the selecting a data point comprises selecting a data point for each of the multiple differences.
12. The method of claim 8 wherein the providing to the at least one of the FMS and the ground station the associated weather data of the selected data point comprises providing the selected data point as at least one of an enroute waypoint, pseudo waypoint or altitude to the at least one of the FMS and the ground station.
13. The method of claim 8 wherein the reference aircraft trajectory comprises at least one of a climb phase, a cruise phase, and a descent phase.
14. The method of claim 8 wherein the determining at least one difference comprises determining the points on the reference aircraft trajectory and the approximate aircraft trajectory where the difference exceeds a difference threshold.
15. The method of claim 8 wherein the satisfying the predetermined threshold comprises the at least one difference being less than a predetermined amount.
16. The method of claim 8 wherein the satisfying the predetermined threshold comprises finding the data set with the lowest error.
17. The method of claim 8 wherein the predetermined error threshold is a predetermined value selected to minimize error in at least one of a predicted time of arrival and a fuel burn.
18. The method of claim 8 , further comprising comparing a last determined at least one difference to a previous determined at least one difference.
19. The method of claim 18 wherein the comparing comprises determining an improvement between the last determined at least one difference and the previous determined at least one difference.
20. The method of claim 19 wherein the at least one difference satisfies the predetermined error threshold when the improvement satisfies a predetermine improvement value.
21. The method of claim 8 , further comprising comparing a cost function between the reduced data set and the reduced data set with the replaced data point.
22. The method of claim 21 wherein the comparing comprises determining an improvement between the reduced data set and the reduced data set with the replaced data point.