Which additive is used to prevent fuel system icing in JP8?

• A. Fuel System Icing Inhibitor (FSII)
• B. Corrosion Inhibitor
• C. Static Dissipation additive
• D. Lubricity enhancer

Answer: (A)

Fuel System Icing Inhibitor is added to JP-8 to fight fuel-system icing. When JP-8 contains water and temperatures drop, ice can form in filters, lines, and injectors, potentially blocking fuel flow. FSII, a glycol-based additive, lowers the effective freezing point of the water and helps keep the water dispersed as very small droplets. It also coats any ice crystals that do form, reducing their growth and how well they stick to fuel-system surfaces. This keeps filters, metering devices, and injectors functioning in cold conditions. Other additives address different issues—corrosion inhibitors protect metal surfaces, static-dissipation additives reduce static electricity, and lubricity enhancers improve lubrication for pumps and injectors—but for preventing fuel-system icing specifically, FSII is the appropriate additive.