Total flights in Irish airspace decreased by 1.2% last month when compared to April 2011, latest figures reveal.
Commercial terminal traffic for Shannon, Dublin and Cork airports dropped by 4.6% in April 2012 compared to the same month last year, according to data from the Irish Aviation Authority (IAA).
The biggest fall was recorded at Shannon, with commercial flights into and out of that airport down almost 10% in the year.
Commercial terminal flights at Cork were down 3.4%, while Dublin Airport recorded a decline of just 0.1% in commercial traffic.
There was an average of 1,460 daily flights during April 2012, the busiest day being April 2 with 1,652 flights in Irish airspace.
The IAA said the overall reduction in traffic was largely attributable to the continued downturn in international arrivals and departures at the three state airports.