EASA AD US-2020-17-02
Engine - Kathon FP 1.5 Biocide in a Fuel Tank or Engine - Removal / Airplane Flight Manual - Revision
Summary
The document titled "Engine - Kathon FP 1.5 Biocide in a Fuel Tank or Engine - Removal / Airplane Flight Manual - Revision" is a Federal Aviation Administration (FAA) Airworthiness Directive affecting certain Boeing 747-8, 747-8F, and 787-8, -9, and -10 airplanes equipped with General Electric GEnx-1B and GEnx-2B model engines. It addresses the unsafe condition caused by the presence of Kathon FP 1.5 biocide in fuel tanks or engines, which can lead to engine control malfunctions and thrust anomalies.
What Changed
This new FAA Airworthiness Directive requires the removal of Kathon FP 1.5 biocide from the fuel tanks and engines, installation of a fuel limitation placard, and revision of the airplane flight manual to prohibit operation with Kathon FP 1.5 biocide present. It introduces mandatory procedures to flush the biocide from the fuel system by operating the airplane for at least 30 flight cycles using only untreated fuel.
Why It Matters
This directive is critical for aviation professionals because the presence of Kathon FP 1.5 biocide in fuel can cause salt crystal formation that impairs engine hydromechanical controls, potentially resulting in compressor stalls, flameouts, or loss of thrust control on both engines. Compliance ensures safe engine operation, reduces risk of in-flight engine anomalies, and prevents forced landings or high pilot workload scenarios.
What To Do
Operators must promptly remove Kathon FP 1.5 biocide from affected fuel tanks and engines, install the required fuel limitation placard, and update the airplane flight manual to prohibit use of this biocide. They must also operate the airplane for at least 30 flight cycles using only untreated fuel to flush the system. The directive became effective on August 25, 2020, and comments were accepted until October 9, 2020.
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