The success of the Wright Flyer in 1903 brought to the world an understanding of the principles of controlled flight and the need for engines which offer high power to weight ratio and good reliability. For the first few decades of flight, the fuel used was a low boiling hydrocarbon gasoline commonly used in ground vehicles. The link between engine operation and fuel quality remained unexplored for several years. That is until the First World War, when the need for reliability and high-power output led to the introduction of aviation gasoline (Avgas). This high quality fuel was, and still is, specifically designed for use in spark ignition piston engines.
Initially developed as an unleaded fuel, a lead additive – Tetra Ethyl Lead (TEL) - was introduced around 80 years ago. TEL has been a vital ingredient in achieving the high octane quality of Avgas. The current grade Avgas 100LL (low lead), which was introduced in the 1970s, is still widely available around the world.
However, environmental pressures to eliminate the use of lead and seek cleaner, greener fuels now face the industry. Air bp introduced unleaded Avgas (UL91) in 2016 and will continue to explore and develop unleaded fuel options to satisfy demand.
The arrival of jet engines in the 1930s and 1940s signalled another challenge for fuelling engineers. Avgas is flammable down to about -40 °C, so you could be standing at the north pole with a cup of Avgas, light a match and it will burst into flames. A jet engine doesn’t require fuel that vaporises quite so easily. So, instead of using gasoline engineers turned to a kerosene mix.
With a low freeze point, kerosene can stay liquid down to -47 °C and below. Plus, it can be heated up to 38 °C before it will catch fire. The Jet fuel Air bp uses now is made using pure kerosene and the most widely used specifications are Jet A and Jet A-1.
Looking ahead it’s the development of sustainable aviation fuel (SAF) that is key to changing the face of the aviation industry. SAF is made by converting sustainable material such as recycled cooking oil or solid household waste or vegetable oil to a high-quality synthetic product, which is then blended with regular jet fuel.
At the end of 2018 we entered into an agreement with Neste, one of the world’s leading renewable products producers, to increase the supply and availability of SAF. SAF is made from non-palm renewable and sustainable raw materials including used cooking oil. Additionally, in 2016 bp announced an investment of $30 million in biojet producer Fulcrum BioEnergy. Fulcrum has developed and demonstrated a reliable and efficient process for producing low-cost, sustainable aviation fuel from municipal solid waste (MSW). What’s more it helps reduce landfill waste. The first plant is under construction in Reno, Nevada. These fuels can reduce the carbon footprint of aviation fuel by an impressive 80% over their full life cycle.
Fuelling technology has also come a long way over the last century. In 1927, our second year of operations, Air bp supplied 2,582 gallons of aviation fuel. Leap forward to the present day and we currently supply around 6.6 billion gallons each year with the ability to fuel large passenger jets with up to 4,000 litres per minute. And while it might once have been common to use a chamois cloth at the end of the hose to filter fuel, filtration technology has also evolved, catching trace dirt and water at parts per million level.
Going forward the challenge is to meet continuing passenger growth in a responsible and sustainable manner. Emerging technologies are reshaping the industry with the push for hybrid and electric aircraft, unmanned aircraft systems, robotics and artificial intelligence all playing a role in aviation’s future. But as engines and aircraft become lighter, quieter, faster and more efficient Air bp’s role ultimately is to continue supplying the industry’s aviation fuel needs safely and reliably. And we’re ready to do just that.