Vertical Grid Shifting Approach to the Development of Contrail Reduction Strategies with Sector Capacity Constraints

Many strategies have been proposed to reduce contrail formation in the United States airspace. One approach is to build three-dimensional weather grids and have aircraft cruising at different flight levels to avoid the persistent contrail potential area with the consideration to constraints like fuel burn, flight level capacity, and total operations of climbing/descending aircraft count at each level. However, there is no air traffic control regulation defining the flight level capacity and the total number of climbing/descending aircraft operations for each flight level. This paper presents a contrail reduction scheme, which considers the defined Monitor Alert Parameter value as the sector capacity constraint. Instead of shifting (changing cruise altitude among vertical grids) for all aircraft in a center, the new scheme only shifts certain aircraft out of those grids that are within the persistent contrail potential area. Compared with the level shifting scheme, the grid shifting has a finer resolution and brings the benefits of more contrail reduction and less fuel burn. Furthermore, the one-hour planning interval is changed to one-minute, which provides higher temporal resolution in solution results. Numerical experiments are performed to compare the new vertical grid shifting scheme with the previous level shifting scheme.