More than one in three flights were delayed in the third quarter of the year, according to the study by the Association of European Airlines.
The study found 35.5 percent of flights were delayed arriving for more than 15 minutes and the average delay was for 39.3 minutes.
For departing travelers, the situation was worse, with 36.6 percent of flights hit and the average delay lasting 45.5 minutes.
Worst hit for departures were Air Malta flights, which averaged 57.4 minutes behind schedule. Austrian Airlines were worst hit for arrivals, with average delays of 84.8 minutes.
The main causes of the delays were late arrivals, airport and air traffic control, loading and handling aircraft and maintenance.
Of the 27 airports surveyed, Dublin was one of six where delays had got worse compared to the previous quarter.
Dublin was also one of the few airports that had no delays due to weather problems.
The Nordic countries came out best in the survey. Helsinki, with only 8 percent of flights delayed, was top of the league, closely followed by Oslo, Stockholm and Copenhagen.