Jet engines primarily operate on fuels similar to kerosene, not gasoline, due to gasoline's volatility and explosive potential. Alternative fuels, such as hydrogen, are possible, but they require specific adaptations for effective use. Research into fuel additives, like boron, has explored ways to enhance performance, although practical implementation has faced challenges. The efficiency of jet engines is influenced by the energy content of the fuel used, similar to internal combustion engines. Water injection can also be utilized to improve performance, demonstrating the ongoing innovation in fuel technology for aviation.