What exactly are your goals for using WoW?  Is it to get an overview of all the major processes in airport operations?  Who will your facilitation group include?  How many of them are there?

I find WoW works welll if you have a group of 8+ people that cover off all the functional areas you have to assess.  With smaller groups I would suggest more traditional brainstorming or scenario-driven techniques (e.g. start with the air traffic controllers and say "What do you do in a typical day?"), as I find WoW is best used to help consolidate a vast quantity of thoughts and suggestions from a large group into a manageable set of information.