On Sunday, Greek airspace closed. A strange radio noise stopped flights. This was a big problem for travel. The Hellenic Civil Aviation Authority said it was new. Loud electronic noise made it hard to talk. Air traffic controllers needed to communicate. They took quick actions to keep planes safe. The problem started at 8:59 in the morning. It was a busy travel day.
The cause of the noise was not found. People thought it was a machine problem. Air traffic in Athens was less. Planes could not talk to controllers well. So, flights changed paths. They did not fly over Greece. Flights took longer. Many travellers were late.
A special plane with experts looked for the noise. Teams checked machines on the ground. Communication was bad. So, fewer planes could fly. Only 35 planes each hour. Planes waited four minutes to leave.
Many flights were late. Eight planes in Athens went back. Three flights went to other airports. About 75 flights in Athens were very late. Cyprus also had problems. About 500 people in Larnaca had late or cancelled flights. Greek planes could not fly. Travel was late all night.
Flight safety was okay. They used other radio ways. By 4 PM, more planes could fly. Flights started to be normal. They will find out why the noise happened.