What are the five fuel contaminants?

The five fuel contaminants that are critical to understand when discussing the quality and safety of fuel include sediment, water, micro-biological organisms, other fuel, and ballistic gel.

Sediment refers to particulate matter that can accumulate in fuel tanks and lines, potentially obstructing fuel flow. Water, as a contaminant, can promote microbial growth and cause fuel degradation. Micro-biological organisms, including bacteria and fungi, can thrive in the water that settles in fuel systems, leading to sludge formation and compromising fuel integrity. Other fuel refers to the unintended mixing of different types or grades of fuel, which can alter performance characteristics and combustion efficiency. Ballistic gel, while not a typical contaminant, may be mentioned in some industry contexts regarding specific applications, but it's not commonly recognized as a fuel contaminant compared to the other options listed.

The combination of these contaminants can significantly affect engine performance, lead to corrosion, and result in costly damages or failures within the fuel system. This is why identifying and understanding these contaminants is essential for maintaining fuel quality and ensuring the efficient operation of aircraft systems.