berlin berliners vote keep historic tegel airport open even new international hub complete create headache german capital government want close tegel spring 90 days 1948 support berlin airlift huge operation ship supply thwart cold war soviet blockade much-loved many berliners business travelers proximity city center berlin government rethink plan close tegel 56 percent voters support non-binding referendum sunday day germany federal election reconsider proposal envisage close tegel six months berlin brandenburg international ber airport grand project bedevil repeat construction plan problems finally start operate still fix open date michael mueller berlin mayor say result create difficult situation tell rbb radio would talk airport state owners take different approach could legally financially challenge chief executive berlin airport engelbert luetke dalderup say airport owners decide operator work aim complete construction work ber august 2018. opponents argue tegel concrete hexagonal terminal date back 1970s antiquate meet current safety standards must renovate cost least billion euros 1.2 billion want state government go ahead plan convert site new business technology park boost berlin economy build affordable flats alleviate house shortage supporters however say even complete new airport small meet passenger demand want tegel retain serve around 10 million passengers per year mainly short-haul flight airlines also divide ryanair call keep open avoid capacity crunch lufthansa say would prefer operate one airport ryanair place posters around berlin urge locals vote keep tegel open monday welcome result call government explore options keep open berlin vote keep cold war era tegel airport open