What happened
On September 18, 2013, a Boeing 787-8 operated by LOT Polish Airlines, registration SP-LRB, was performing a cruise flight from Beijing Capital International Airport (ZBAA) to Warsaw Chopin Airport (EPWA). During the flight, the crew received a maintenance status message indicating "ENG FUEL FULTER R".
Upon arrival at the destination, maintenance personnel inspected the aircraft and discovered that the engine fuel filter for the No. 2 (right) engine had not been installed. A subsequent inspection of the left engine on the same aircraft, SP-LRB, revealed that its fuel filter was also missing.
On September 19, 2013, a second Boeing 787-8, registration SP-LRC, was inspected and found to also be missing its engine fuel filters.