FAA And EASA Warn Against A Certain A320neo Engine Treatment

A preservative used in jet fuel is in the spotlight following an airworthiness directive issued by both the European Union Aviation Safety Agency and the Federal Aviation Administration. The preservative could cause engine performance to reduce, possibly reducing control of the aircraft.

Airlines use a popular preservative called KATHON FP 1.5 biocide to counter microbial contamination and other operational problems in refined fuel. But according to both EASA and the FAA, it is potentially unsafe.

Particular Airbus A319, A320, and A321 models use the KATHON FP 1.5 biocide . The airworthiness directive targets aircraft from the A320 family. Airlines will no longer be able to operate flights using fuel mixed with KATHON FP 1.5 biocide. The directives also require flushing and cleaning of fuel systems of affected planes.

"This AD prohibits aeroplane flight operation with fuel mixed with KATHON FP 1.5 biocide and requires KATHON removal, as defined in this AD, from aeroplanes which have been previously operated or stored with fuel mixed with KATHON FP 1.5 biocide," states the EASA airworthiness directive.

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EASA took the lead on this matter, issuing their directive on August 5. The FAA followed in EASA's footsteps, issuing their airworthiness directive on Monday.

"This AD was prompted by a report indicating that Kathon FP 1.5 biocide added to fuel and running through an airplane's engines can lead to engine performance degradation," says the FAA directive.

The FAA directive targets all Airbus SAS Model A319-151N and -153N; A320-251N, -252N, and -253N; and A321-251N, -252N, -253N, -251NX, -252NX, and -253NX aircraft.

According to the FAA, 163 aircraft across the United States are impacted. The FAA estimates it will cost just over US$2000 per plane to clean out the fuel systems and take about 24 man-hours.

The safety regulators acknowledge that preservatives play an important role in reducing the threat of fuel contamination. Waterborne micro-organisms can collect in fuel tanks, feeding off hydrocarbons in the fuel. Preservatives such as KATHON FP 1.5 biocide deal with this.

But EASA, in particular, has long had KATHON FP 1.5 biocide in its sights. They say there have been several incidents involving "adverse engine effects" after using the perservative.

Concerns at Airbus and some previous incidents caused the manufacturer, DuPont, to get on the front foot earlier this year and tell airlines not to use the product. Until then, KATHON FP 1.5 biocide was one of the most popular fuel preservatives on the market.

In July, the FAA issued another airworthiness directive. This directive banned the use of KATHON FP 1.5 biocide across Boeing's 737 MAX aircraft. While the MAX fleet remains grounded for other reasons, the directive impacts almost all MAX aircraft delivered across the United States so far. It is another MAX related headache for beleaguered MAX owners and Boeing itself.

In March, Australia's aviation safety regulator issued an airworthiness notice suspending the use of Kathon biocide for treating micro-biological growth in aviation fuel. That came after an Australian registered Dreamliner was involved in an inflight incident that;

"Indicates that either an over-dosing maintenance error occurred during a fuel system biocide treatment procedure or that the GEnx engine's fuel system's sensitivity to the biocide may have significantly compromised normal operation of both engines."

While the use of KATHON FP 1.5 biocide across the airline industry may at an end, never fear for DuPont. Their fuel preservative remains popular and approved for use across shipping, resources, and rail industries.

Lead Journalist - Southwest Pacific -.A Masters level education and appetite for travel combine to make Andrew an incredible aviation brain with decades of insight behind him. Andrew's first-hand knowledge of the challenges and opportunities facing Australian airlines adds exciting depth and color to his work. Andrew is based in Sydney.