Passengers hoping to fly out of Sydney Airport have been told to expect delays of at least an hour on Saturday. Reduced air traffic control staff is believed to be at the centre of the issue which delayed more than 120 flights by about 90 minutes on Friday. WATCH THE VIDEO ABOVE: Sydney Airport delays to last all day amid controller shortageSign up to The Nightly's newsletters. Airservices previously said that “air traffic controllers are incredibly proud and dedicated to performing what is a demanding, safety-critical role”. “These air traffic controllers are very skilled, very professional people, they run a very safe operation, but there just aren’t enough.