Assessment of Potential Benefit of Formation Flight at Preliminary Aircraft Design Level

Abstract

In order to close the gap between formation induced drag calculation and the estimation of formation flight benefit at preliminary aircraft design level, a framework for fast assessment of formation aircraft performance has been developed at the Institute of Aerospace Systems (ILR) of RWTH Aachen University. By integrating the aerodynamic methodology into the in-house preliminary aircraft design platform, the framework can estimate the potential induced drag reduction for arbitrary aircraft configurations in formation. For specific flight missions, the block fuel reduction can be determined. As a result, formation flight impact on fuel consumption related emissions and direct operating costs (DOC) can be quantified. The presented results show that a block fuel reduction up to 16% can be expected with two short range commercial aircraft in formation, which corresponds to a cruise flight CO2 reduction around 20% and a DOC savings of more than 6%. For the case of two long range aircraft in formation, the results show slightly more benefit when compared with the short range aircraft. At the very end, this paper briefly investigates the operational considerations of formation flight.