We have let's say 10 private planes that we use to transport customers. Each customer has their own departure and arrival airports. I am trying to see if Excel Solver can help me decide which plane to use for any of the customers based upon closeness and meeting the departure/arrival time in each case. It doesn't make sense to reposition a plane to a far customer site when I can use another plane that just landed to a closer city. So to elaborate this a little more let's say Plane A landed in Columbus, OH and I have a customer that needs to be picked up in Cleveland, OH in about 2 hours. I would need the solver to tell me Plane A is my best choice based upon the closeness of Columbus, OH and Cleveland, OH. Can someone give me an example of this sort with departure time constraints? I have an example excel document but couldn't attach it here. Please let me know.