###### Abstract
The reduction was also observed in C.O. and NO emissions. [PERSON] et al. [14] compared gas turbine engine performance and emissions for pure Jet A-1 and 20% blend with soap-derived bio-kerosene. Both fuels have similar performance parameters when looking at engine efficiency, specific fuel combustion, turbine inlet temperature, and exhaust gas temperature. However, an increase in C.O. and H.C. emissions and differences in NOx were registered. In their research, [PERSON] et al. [15] looked at the emission and performance characteristics of the blends of Jet A-1 and Spirulina biofuel with a blend ratio ranging from 20% to 100% using a small experimental engine. It was concluded that lower blendingrations had positive results in terms of both emissions and performance, and a higher proportion of biofuel resulted in an undesirable decrease in energy. [PERSON] et al. [16] studied the performance and emission characteristics of blends of Jet A-1 fuel with biodiesel with a blending ratio ranging from 10% to 30%, with the addition of 5% of Aeroshell Oil 500. The experiment was conducted on the JETCAT P80 micro-engine at three working regimes. It was concluded that all three blends have shown reduced emissions and proved to be stable for utilization at all three engine regimes. [PERSON] et al. [17] have reviewed information related to biofuel emulsions, focusing on the preparation of stable emulsion, the effects of water and its fuel properties, and methods for improving its performance and emission characteristics. If we look at the academic literature concerning emissions from alternative aviation fuels, in their work, [PERSON] et al. [18] present a classification of alternative fuels and their gaseous and particulate matter (PM) emissions as compared with fossil fuels. They concluded that while researched alternative jet fuels have great potential in alleviating carbon emissions, their gaseous emissions vary and are highly dependent on numerous factors. [PERSON] et al. [19] conducted the experiment comparing the PM emissions from a small turbofan for neat Jet A-1 and 5, 20, and 30% blends with alcohol to synthetic jet kerosene. As expected, the experiment concluded that the lowest PM number emission index was achieved with the ATJ 30% blend, and the highest was for neat Jet A-1. [PERSON] et al. [20] analyzed the performance and emission characteristics of Jet A-1 fuel blend with canola and solid waste pyrolysis oils. The reduction in fuel consumption is linked to an increase in static thrust. Higher proportions of ethanol lead to an increase in thermal efficiency and oxygen content. A reduction in C.O., CO\({}_{2}\), and NOx emissions was observed, which can be further optimized by the addition of hydrogen. Focusing on the performance of engines running on alternative aviation fuels, [PERSON] et al. [21] studied the effects of the heat capacity and density of biofuels on aircraft engine performance. The study was based on the simulations using Jatropha Bio-synthetic Paraffinic Kerosene (JSPK) and Camelina Bio-synthetic Paraffinic Kerosene (CSPK) biofuels focusing on the thrust and fuel consumption. The simulations recorded an increase in the engine thrust and a reduction in fuel consumption with a rising percentage of biofuel in the mixture. [PERSON], [PERSON], and [PERSON] [22] evaluated jet engine operational parameters while using conventional and alternative aviation fuels. Their bench test concluded that using fuels with plant oil additives provides more energy efficient operation as it improves jet engine thrust and reduces fuel flow. Moreover, blends with alternative fuels result in the decrease in NOx emissions and increased resistance of engine materials and structure against high temperatures. In their study, [PERSON] et al. [23] conducted an experiment to determine the effects of Jet A-1, diesel fuel, and their various blends on combustion and engine performance in a direct injection diesel engine.