Which fraction of crude oil is typically used for jet fuel?

Kerosene is the correct fraction of crude oil typically used for jet fuel because it has the appropriate properties required for high-performance aviation fuels. Jet fuel, such as Jet A or Jet A-1, is derived primarily from kerosene, which has a lower boiling point than heavier fractions. This allows it to remain liquid at the lower temperatures encountered at high altitudes, while still providing a high energy content critical for the efficient operation of jet engines. Kerosene's chemical composition also ensures that it burns cleanly and efficiently, producing fewer pollutants compared to heavier fractions.

In contrast, diesel is designed specifically for diesel engines and has a different combustion profile, while heavy fuel oil is too viscous and has a higher boiling point, making it unsuitable for aviation use. Liquefied petroleum gases, such as propane and butane, are gases at room temperature and would not provide the necessary energy density or liquid state required for jet fuel applications.