Canberra (dpa) - In an inspection of its fleet of Boeing 737 NG passenger jets, the Australian airline Qantas has already discovered three hairline machines. The cracks were at a point where the wings are attached to the fuselage. The affected machines were withdrawn from circulation, it was said. The Boeing 737 NG is the predecessor of the 737 Max. The 737 Max models have been banned since mid-March due to two crashes with a total of 346 dead.