Preventing the formation of ice in aviation fuels
At high altitudes and/or low temperatures, free water in aviation fuels can crystallize and block fuel filters. Despite the stringent measures which have been put in place to eliminate water from aviation fuels, the possibility of free water contamination still exists.
In civilian aircraft, fuel heaters can help to minimize the formation of ice in fuels. However, military aircraft do not generally use these heaters, due to restrictive weight requirements.
Fuel System Icing Inhibitor (FSII) acts to prevent the formation of ice crystals, providing additional security in the event of free water contamination in aviation fuel. It is a mandatory additive in many military aviation fuel specifications.
FSII dissolves sparingly in fuel but more easily in water. Any water present will extract FSII from the fuel; the additive then acts to reduce the freezing point of the free water, preventing the formation of solid ice crystals, which could block the fuel supply system.
Innospec’s FSII-41 ice inhibitor is based on Di-Ethylene Glycol Monomethyl Ether (DiEGME) chemistry, the preferred solution for today’s market.
The additive is suitable for use in either aviation turbine fuel (jet fuel) or aviation gasoline, subject to specification requirements and approvals. Diethylene Glycol Monomethyl Ether, known in the industry as DIEGME and FSII-41 is an aviation additive utilized to inhibit the formation of ice crystals in aviation fuel systems.
The material is approved for use in both military (MIL-PRF -5624, MIL-PRF-83133, MIL-PRF- 83133) and commercial (ASTM 1655) jet fuels as well as U.K. Ministry of Defense Standards (Joint Military and Civil).
• Jet Fuels
• Kerosene
• Heating Oils
• Diesel Fuels
• Greases
• Gasoline
DIEGME may also be used in non-aviation fuels to address the possible presence and impact of water.
DIGME meets 40CFR80.591 requirement for use in ULSD fuels. Application To inhibit icing in aviation fuel systems in military (MIL-PRF-5624, MIL- PRF-83133) and commercial (ASTM 1655) jet fuels and U.K. Joint Military and Civil fuels. Approvals DIEGME aka FSII or FSII-41 has been approved under the following specifications:
FSII specifications:
• ASTM D4171 (Type III)
• DEF STAN 68-252
• MIL-DTL-85470B
Aviation Gasoline:
• ASTM D910 Aviation Turbine Fuel:
•ASTM D1655
• MIL-DTL-5624
• MIL-DTL-83133
• DEF STAN 91-91
Qualification Ref
• DEF STAN 91-86
• DEF STAN 91-87
• DEF STAN 91-88
• Meets MIL-I-85470B and ASTM D4171 requirements