Relationship between fuel consumption and altitude for commercial aircraft during descent: Preliminary assessment with a genetic algorithm

Despite fuel flow rates being low during descent compared to climb and cruise, the potential exists for significant fuel savings during that phase of flight. Increased fuel use, costs and related environmental impacts are associated with stepped descents leading to low level flights and holding in the air due to delays or slot conflicts. Except for the Base of Aircraft Data (BADA) model, little research has been reported on this relationship for aircraft fuel consumption. In this study, the negative impact of low level flight is examined and a relationship between fuel consumption and altitude established using real flight data and the genetic algorithm (GA) technique. Exponential models are established between fuel consumption and altitude, and corresponding results exhibit similar model coefficients and low residuals for three of four flights. Moreover, it is found that the relationship between fuel flow and altitude for similar flight configurations in the descent phase can be explained by a generic exponential model.