August 2024 - F.E.S. TANKS

Jet A1 fuel – what it is and top storage tips

Fuel security is a hot issue for Australia’s aviation industry. With 90 per cent of liquid fuel – including jet fuel – imported through long supply chains, supply is subject to geopolitical tensions, delays and quality issues.

The effect on price is predictable. Jet fuel prices in Australia are still well above pre-pandemic levels – causing a hit to the bottom line for aviation businesses and to the hip pocket for consumers.

The CSIRO is working with the aviation industry to develop new types of sustainable aviation fuel that will help reduce reliance on imports and lower prices, but in the meantime Jet A1 fuel is the most common fuel used in Australian turbine aircraft.

Given the cost of fuel makes up around a third of airline operating costs, getting Jet A1 storage right and minimising waste is an important part of sustainable operations for any aviation-based business.

What is Jet A1 fuel?

Jet fuel is a kerosene-based fuel similar to diesel and is the leading aviation fuel type for turbine-engine aircraft – from commercial jets to cargo aircraft, military airplanes and more. It is generally more stable and more widely available than avgas, with different properties that make it more suited to jet engines and to flying through different climactic conditions.

Because its exact composition varies, jet fuel is defined using performance specifications and requirements including freezing point and smoke point.

There are three main jet fuel varieties made from either unleaded kerosene (Jet A and Jet A-1) or a naphtha-kerosene blend (Jet B).

Jet A has been used primarily in the United States since the 1950s. This fuel is developed to be heavier with a higher flash point and freezing point than standard kerosene. Both Jet A and Jet A1 have a flashpoint higher than 38 °C with an autoignition temperature of 210 °C.

Jet A1 is the most used jet fuel worldwide. Jet A1 has a lower freezing point (-47° C) than Jet A (-40° C) so it is especially suitable for international travel through varying climates. This type of fuel also contains mandatory static dissipater additives that decrease static charges that form during movement.

Jet B is a naptha-kerosene fuel with a uniquely low freezing point of -60° C, making it useful in extremely cold areas. It’s what’s known as a “wide cut fuel”, made from a blend of about 30% kerosene and 70% gasoline. However, Jet B’s lighter composition makes it more dangerous to handle and it has a low flashpoint. It is primarily used in northern Canada and Alaska, where the extreme cold makes its low freezing point necessary.

Contamination risks for Jet A1 fuel

Because of its kerosene base, Jet A1 fuel is less volatile than Avgas and can generally be stored for longer – particularly in the right conditions.

But it’s still vulnerable to common causes of fuel contamination.

Water contamination: Free water in aviation fuel can lead to ice formation, filter blockages and engine failure. It can also allow microbial growth in fuel tanks, which can cause fuel spoiling and filter blocking. Acids generated by the microbes can even cause corrosion damage. Water can get into insecure storage tanks during transfer or through condensation, particularly if the structure of the tank provides natural collection points like baffles. The most common way of testing for water in fuel is to use a water detector tablet or capsule, which can indicate whether the water level is above or below 30 ppm, the maximum allowed limit.

Particulates: Metals like copper react with jet fuel, causing serious issues and fuel instability even at very small concentrations. Rust in fuel storage tanks or fittings is another common source of particles that can eventually entering the fuel. This is why under Australian safety regulations, any part of a storage tank that could come into contact with jet fuel must be stainless steel.

Microbes: Microorganisms found in jet fuels include bacteria, yeasts and fungi. As they grow, these organisms can form solid debris that can block and damage fuel filters. Some microorganisms also produce acids that can accelerate metal corrosion. Since most microorganisms need free water to grow, this kind of contamination is most commonly found anywhere fuel meets water.

Incorrect fuel/misfuelling: Mixing aviation fuels can prove disastrous in terms of cost and safety. Jet A1 can cause engine failure quickly in an avgas-powered engine. The aviation industry uses a uniform marking code for fuel storage tanks as one way of protecting against grade mixing contamination and errors. Jet A1 tanks are clearly marked with two black bands.

Your Jet A1 fuel storage checklist

The good news is that getting storage right can help you make the most out of your Jet A1 fuel and keep your aviation business operating smoothly.

There are some simple things to look out for when choosing Jet A1 storage.

Quality manufacture: Look for stainless steel for a long-lasting Jet A1 storage tank that will help keep your fuel safe. This will also reduce the risk of water contamination due to rusting that compromises tank integrity. F.E.S Tanks self-bunded aviation tanks have a 100% stainless steel inner tank and all fittings are also made of stainless steel. This not only meets all safety requirements and is very long lasting, but also gives you complete peace of mind on the operational integrity of the tank overall.
Easy installation and maintenance: The best way to keep fuel safe is to regularly check the integrity of storage tanks. The F.E.S range of self-bunded double walled tanks can be easily installed on most sites – there is no longer a need to build expensive underground storage with all the decontamination issues that involves. What’s more, our aviation fuel tanks are coated to twice the thickness of many others, for a much longer life.
Avoid baffles: Some manufacturers use baffles as part of the structural integrity of the tank construction or to keep fuel stable, but baffles can act as collection points for water condensation – something best avoided when storing Jet A1 fuel. F.E.S. aviation fuel tanks are made without an interior baffle, ensuring a free drainage floor pan and allowing for the safe removal of water from aviation fuel as part of your daily maintenance program.
Safety standards: In Australia, Jet A1 fuel tanks must meet AS1692 and AS1940. F.E.S. aviation fuel tanks are all made to Australian Standards in a spotlessly clean, purpose-built manufacturing facility. Each tank is inspected regularly during the manufacturing process, before it leaves the factory and when it arrives at the destination.

Portable Jet A1 Storage and Refuelling Station

Whether you’re storing 1000 litres or 100,000 litres, get in touch with our expert team to discuss a Jet A1aviation fuel storage solution that’s right for you.

Contact the experts at F.E.S. TANKS to find out more on 1300 651 391.

What is a Diesel Bug?

A diesel bug is a common term for a myriad of microscopic organisms that grow in the fuel-water interface present in any static bodies of diesel – particularly fuel tanks. From yeasts, to fungi and algae, these bugs share a few typical features.

They require water and warmth for growth.
A fast reproductive cycle allows them to multiply in numbers very quickly.
As the older ‘bugs’ die their bodies and waste products accumulate in the tank.
This results in the formation of a layer of sludge and slime.

Whilst you may or may not have heard of the term “diesel bug” or “diesel bug contamination”, you may have heard of “fuel contamination” which can be very closely linked to the presence of water and diesel bugs.

Did you know your tank breathes?

When we talk about air and water in tanks, they often exist together – and one of the reasons is because your tank breathes.

Each day, either through temperature fluctuation or the movement of fuel, the air pocket within a tank expands and contracts. This is why storage tanks are fitted with a breather – a valve that allows the tank to relieve this excess pressure and vacuum.

As air is introduced via the breather, it brings moisture in from the atmosphere with it, and cooler conditions within the tank can allow this moisture to condense. As these little droplets of water collect, they eventually fall into the fuel itself, and create a water-fuel interface – the perfect home for diesel bugs.

A full tank has limited airspace for the transfer of moisture via condensation.

Each of these droplets is like a swimming pool of space for more microbes and spores to colonize. With a constant supply of energy from the diesel, and dissolved oxygen from the water, this creates a perfect environment for these bugs to quickly take over.

Over time, if these water and bug issues are not handled correctly, there is a real risk of structural and mechanical damage to contaminated tanks, vessels, vehicles and machinery.

Slime, Grit & Machine Failure – Is Your Fuel Contaminated?

Sometimes the first symptoms of diesel bugs and contaminated fuel are not noticed, but the consequences cost us countless dollars each year in maintenance and damages.

If you notice any of these tell-tale signs, make sure to inspect your tank, and if you are unsure how, always check with your supplier –

Clogged filters & the presence of slime or grit on tank floors.
Pitted or corroded components in machinery and fuel systems.
Darker fuel, or the presence of a foul smell.
Rough running machinery from a particular fuel source or tank.

Any of these symptoms are indicators that fuel contamination may be affecting your diesel systems, and the key is vigilance, inspection and treatment before the problem multiplies.

Catching the Bugs – Inspection Protocol & Treatment

Ideally, inspection protocols and the correct treatment programs will allow us to identify, control, and protect our fuel reserves from diesel bugs. So what steps do we recommend?

The correct inspection protocols can catch fuel contamination before damages occur.

Prevention

For prevention, we recommend diesel biocide products. While these agents are great at controlling the numbers of living bugs – they do not remove existing sludge and slime, as this is primarily composed of dead bugs and their waste products.

These biocide products are not a permanent solution. Similar to hospitals and antibiotics – diesel bugs within your tank may develop resistance to these products, so we advise to use them appropriately as a preventive agent and to ask us for advice if you feel they are being overused.

Inspection & Fuel Testing

Inspecting your tanks regularly is a vital part to maintaining any fuel storage system, and many tanks have inspection hatches for this purposes.

Inspection routines should include monitoring your tank temperature, checking for leaks or checking for water in fuel reserves. Also, water condensation can be minimized by trying to keep the tanks full, and appropriate monitoring of tank levels is of utmost importance.

An extra level of safety can be gained by applying fuel testing methods to your maintenance schedule. This is particularly valuable as by testing the fuel itself, you can detect contamination that may not be visible to the naked eye or via inspection hatches.

Draining, Cleaning & Fuel Polishing

A tried and true method, draining and cleaning your fuel tank is essential to routine maintenance and should be performed at regular intervals as advised by your suppliers and local guidelines.

Any fuel removed during these processes can also be filtered and conditioned, which is commonly known as fuel polishing.

Fuel polishing is a series of filtration techniques designed to eliminate contamination, and in some scenarios can even save some of your fuel from being discarded.

Draining and cleaning is an ideal time to make sure that all water and existing debris is removed from your fuels.

Should you have any concerns or issues and require a second opinion, please get in touch for a chat.

Jet A1 aviation fuel – a turbo charged fuel source