Two of five Boeing 787 Dreamliners owned by Poland\'s flagship carrier LOT were missing oil filters, creating an aviation hazard, the airline said Wednesday. \"Monitoring systems during a flight signalled a problem in the fuel system of one of the motors. The problem was fixed in cooperation with Boeing,\" LOT deputy chief Tomasz Balcerzak told reporters in Warsaw Technicians found the filters were missing, he explained. \"To avoid similar problems on other 787s, we asked Boeing for extra checks,\" he added. The further checks turned up the same problem in another of the five Dreamliners owned by LOT, Blacerzak confirmed. In April, Poland moved towards fully privatising the airline, which ended 2012 with an operating loss of 115 million zloty (28 million euros, $36 million), instead of a forecast profit of 52.5 million zloty. The state owns 67.97 percent of the carrier, which employed 2,063 people at the end of 2012, but has said it will axe 500 jobs this year. The troubled company had pegged its hopes on the fuel-efficient Dreamliner, becoming the first in Europe to use the plane. But the plan has been thwarted by a series of mechanical glitches plaguing Boeing\'s newest aircraft.