FSII

Prist®

D ice®

Description

A Fuel System Icing Inhibitor (FSII) is a manufactured fluid which, when added to aviation fuels, helps to prevent the formation of ice crystals in filters, fuel lines and other fuel system components. In many localities, FSII is referred to by the registered, generic trademark "Prist", in others as "D ice".

Discussion

Stringent measures have been put into place, during production, transport, storage and aircraft uplift, to eliminate water from aviation fuel. Despite these measures, the possibility of free water contamination of aviation fuel still exists. In conditions of low temperature and/or at high altitude, any free water in the fuel can crystallize and block fuel filters, fuel pump screens, fuel lines or other fuel system components. These blockages have the potential to cause loss of power, engine rollback or flameout.