The nearest public transport that goes to the airport is bus line 18. If you are going directly to the terminal, get off at the stop "Kláštorská ul., Letisko", if you are going to the museum, your stop will be "Jánošíkova ul. střed". The bus runs from 6:00 to 18:45 once every hour or so(timetable) and the ticket costs €0.50.