The potential for using fuzzy set theory in airline network design

This paper develops a model to design an arline network and determine flight frequencies. The basic input data are the estimated numbers of passengers between pairs of cities. It is often impossible to estimate these numbers with enough precision (i.e. there is a degree of uncertainty surrounding the numbers of passengers between pairs of cities). Uncertainty is also frequent in the estimation of future airline carrier costs. The fuzzy set theory is an extremely convenient mathematical device with which to solve problems containing uncertainty, subjectivity, ambiguity and indetermination. Without aspiring to revolutionize airline network design, the basic goal of this paper is to present the fuzzy set tools and their potential application to a generic airline network design problem. The model developed is based on the fuzzy set theory. The first part of the model uses fuzzy logic to determine the route candidates to make the flights, and the second part of the model is based on fuzzy linear programming to determine flight frequencies on the route candidates. The model is supported by numerical examples.