  We present a decision support framework for optimal flight rescheduling on an
airline's day of operations when de-icing becomes necessary due to snow and ice
events. Winter weather, especially in areas where such weather is not
commonplace, often causes cascading delays and cancellations throughout the
system due to the unforeseen need to add de-ice time to each aircraft's
turnaround time. Our model optimally reschedules remaining flights of the day
to minimize system delays and cancellations. The model is formulated as a mixed
integer linear program (MILP). Structural properties of the model allow it to
be decomposed into a finite set of linear programs (LP) and a computationally
tractable algorithm for its solution is described. Finally, numerical
simulations are presented for a case study of Horizon Air, a regional airline
based in the Pacific Northwest of the United States.
