Fuel Tank Ignition Could Occur Due To Overheating Hydraulic System
EASA has issued an emergency AD (2017-0154-E) for all Airbus A350-941 airplanes following the recent discovery of an overheat failure mode of the the A350 hydraulic Engine Driven Pump (EDP). Such EDP failure may cause a fast temperature rise of the hydraulic fluid. This condition, if not detected and corrected, combined with an inoperative Fuel Tank Inerting System (FTIS), could lead to an uncontrolled overheat of the hydraulic fluid, possibly resulting in ignition of the fuel-air mixture in the affected fuel tank.