Aviation fuel of aircrafts is one of the most important and predominant expenditures in air companies. The recent jump on petroleum price has increased the price of equipments and maintenance. Therefore, many aircraft companies look for different ways to reduce their expenditures as much as they can. In this article, we study effective factors to reduce the fuel consumption. The proposed study of this paper gathers different criteria, which are important for cost reduction plans based on experts & apos; point of view. We take advantages of quantitative and qualitative characteristics of criteria and experts & apos; ideas using fuzzy decision making. Finally, a list of effective factors to reduce the fuel consumption is presented based on order of their importance.