Optimization of aircraft fuel consumption and reduction of pollutant emissions: Environmental impact assessment

Abstract

Environmental impact of aircraft emissions can be addressed in two ways. Air quality impact occurs during landings and takeoffs while in-flight impact during climbs and cruises influences climate change, ozone and UV-radiation. The aim of this paper is to investigate airports related local emissions and fuel consumption (FC). It gives flight path optimization model linked to a dispersion model as well as numerical methods. Operational factors are considered and the cost function integrates objectives taking into account FC and induced pollutant concentrations. We have compared pollutants emitted and their reduction during LTO cycles, optimized flight path and with analysis by Döpelheuer. Pollutants appearing from incomplete and complete combustion processes have been discussed. Because of calculation difficulties, no assessment has been made for the soot, H 2 O and PM 2.5. In addition, because of the low reliability of models quantifying pollutant emissions of the APU, an empirical evaluation has been done. This is based on Benson's fuel flow method. A new model, giving FC and predicting the in-flight emissions, has been developed. It fits with the Boeing FC model. We confirm that FC can be reduced by 3% for takeoffs and 27% for landings. This contributes to analyze the intelligent fuel gauge computing the in-flight fuel flow. Further research is needed to define the role of NO x which is emitted during the combustion process derived from the ambient air, not the fuel. Models are needed for analyzing the effects of fleet composition and engine combinations on emission factors and fuel flow assessment.

Evaluating Methods That Calculate Aircraft Emission Impacts on Air Quality: A Systematic Literature Review

“…The ICAO suggests that their TIM values are appropriate only for the engine certification process and do not represent the actual TIM in real-world aircraft operations [19]. However, some researchers [30,31] still use the ICAO standard TIM values for emission calculation. The ICAO Engine Exhaust Emissions Databank (EEDB) provides the EF and FF based on international standard atmospheric conditions.…”

“…The ICAO standard TIMs are 0.7 min, 2.2 min, 4 min, and 26 min for take-off, climb-out, approach, and idle modes, respectively [19]. Kuzu [30] and Khardi [31] used ICAO standard TIM values. However, these values cannot be applied to each airport, especially as the taxiing time does not directly match every airport [32].…”

“…All airports together represent global data. Mos papers covered local data (31), 20 used regional data, and 9 used global data many researchers limit their study by quantifying the emissions of a particular to the limitations in technology and data accessibility. Some airport-specific fac be considered when assessing air quality around an airport.…”