Information on Jet Fuel
Jet fuel is a clear or straw-colored aviation fuel for use in gas-turbine engine powered aircraft. According to Wikipedia, jet fuel is a kerosene-based fuel containing a plethora of hydrocarbons. Jet fuel is actually similar to diesel fuel – both are kerosene derivatives. However, while all jet fuel types are mostly kerosene, diesel fuel is approximately 75% kerosene with added lubricants.
Jet Fuel Regulation Standards
Jet A is the standard jet fuel of use in the United States, while Jet A-1 is used in Europe and the rest of the world. These jet fuels are each held to high regulatory standards for quality and safety.
ASTM D1655 is the United States’ manufacturing specification for jet fuels, and it is the only standard used for Jet A, which is only used in the United States. DEF STAN 91-91/5 is the manufacturing standard for the rest of the world, and all aircraft outside of the U.S. must meet it.
- Has a maximum acidity limit of 0.10 mg KOH/g.
- Simulated Distillation via method ASTM D2887 is allowed.
DEF STAN 91-91/5:
- Has a maximum acidity limit of 0.015 mg KOH/g.
- Measurement of Total Aromatics via method ASTM D6379/IP436 is allowed.
- An additional measurement of lubricity for Jet A-1 is required.
Types of Jet Fuel
Jet fuel is produced in three varieties – Jet A, Jet A-1, and Jet B. Each variety is characterized by the different additives used in their production.
- Jet A – Jet-A has its beginnings in the 1950s when gasoline was in short supply. The first jet engines actually used pure kerosene. Later, Jet-A, a kerosene/gas blend was introduced. Jet A is the standard jet fuel used in the United States and must meet ASTM specification D1655.
- Jet A-1 – Almost identical to Jet A, Jet A-1 has a lower freezing point and an anti-static additive. It is the international standard of jet fuel and must meet DEF STAN 91-91/5, ASTM D1655-04a, and IATA Guidance Material NATO Code F-35.
- Jet B – This fuel is a naphtha/kerosene blend. Because of its high volatility, it is only used in extremely cold climates where no other fuels function properly.
Common Jet Fuel Additives
UK and international specifications allow for certain jet fuel additives to enhance safety, performance, and shelf life. These additives have undergone scrutiny from both major monitoring agencies for safety.
- Antioxidants – Prevent fuel oxidation leading to viscous deposits which may clog or block fuel lines, posing a threat to safety.
- Antistatic Agents – Prevent static electricity buildup which can lead to sparking and possible fires.
- Corrosion Inhibitors – Protect engine parts from oxidation which leads to rusting over time.
- Antifreeze Additives – All jet fuels today have anti-freezing agents added. Before this standard, planes traveling in extremely cold weather condensation from the engines froze, leading to dangerous engine problems.
- Power Booster – A methanol/water blend is added to jet fuel for use in large passenger and cargo jets to give the necessary power for take-off and high altitude accelerations.
Jet Fuel Storage
Jet fuel must be stored in epoxy lined steel tanks designed specifically for jet fuel use. Tanks should be fully accessible for inspection, testing, and repair. All proper precautions should be taken to ensure fuel efficacy and safety. Learn more about aviation fuel storage.
Jet Fuel Tanks Must Have:
- Access manways
- Positive and manual or electric sumps with a manual drain valves
- Venting and overfill protection as well as alarms
- Standard identification signs on tanks and piping
Jet Fuel Tips
- Check tanks regularly for moisture and drain it off immediately. Water in jet fuel tanks promotes bacterial growth and gumming.
- Keep storage tanks in a cool, dry place away from excessive heat and direct sunlight.
- Regularly inspect tanks for damage or leakages.
Jet Fuel Dispensing
Proper care must be taken when dispensing jet fuel to prevent spilling, overflow, or other hazardous incidences.
- Fuel filters and separators must meet API 1581 criteria.
- Fueling facilities must have Emergency Fuel Shutoff Stations.
- Fueling systems must have a Deadman Control.
- Always use static cable reels to prevent static discharge and sparking.
Always use API 1581 compliant fueling hoses.