Irish air passengers made almost 600 complaints about airline delays, cancellations or being denied boarding to an aircraft in the first half of the year.

Complaints made to the aviation regulator have resulted in compensation of €32,000 and refunds of just over €60,000 with around a third of cases yet to be resolved.

A database of this year's cases details how more than half related to either low-fares airline Ryanair with 172 cases or Aer Lingus with 130 cases.

There were also 33 complaints about TAP Portugal, 30 concerning British Airways, 22 about Lufthansa, and 20 involving Dutch carrier KLM.

The 576 total complaints were made in the period from the start of the year to the middle of June, according to a database released under FOI by the Commission for Aviation Regulation (CAR).

The aviation regulator said that 387 of the cases were already closed while 189 remained under investigation.

Compensation of €32,000 was paid in 49 separate cases for an average settlement of just over €653, according to the records.

The largest payments were €2,400 relating to a delayed Aer Lingus flight in January and the same amount for a delayed Turkish Airlines flight in April.

There were seven separate compensation payments of €1,200 for delays and cancellations of flights and four payments of €1,000.

The aviation regulator also listed 341 cases where no compensation was paid, although refunds were issued in around a quarter of those cases.

There were payments of €60,249 in refunds by airlines for 110 separate trips, with an average payment of €547 made.

The largest refunds were €3,856 paid due to the cancellation of a WestJet flight and €3,455 for the cancellation of an Aer Lingus trip.

There were 16 other refunds of greater than €1,000 - all of them relating to the cancellation of flights by airlines.

In some cases, the refunds were very small with just €6 paid for a delayed Ryanair flight and €21 for a cancelled flight with the same airline.

There were also around 250 cases where neither a refund nor compensation was paid to the passenger.

Of the 576 complaints made, there were 318 of them that related to cancellations – an ongoing problem due to Covid-19 – and another 214 about lengthy delays.

There were also 41 cases where a person was denied boarding to an aircraft, two complaints about "downgrading", and one case logged about "upgrading".

Of the two cases relating to downgrading (both involving Aer Lingus), one remained under investigation while the other has been closed with no compensation or refund paid.

The "upgrading" case also failed and the passenger who complained received no money following their complaint to Aer Lingus.

A spokesman for the Commission for Aviation Regulation said that passengers had rights under EU law to seek compensation for problems involving their flights.

"Our remit in relation to passengers impacted by operational issues is confined to situations where the airline is responsible for disruption due to flight delays, cancelations or denied boarding," he said.

"The Commission investigates complaints from passengers departing from Ireland that falls within the remit of EU Regulation 261 / 2004. Any travel disruption impacting on flights returning to Ireland from destinations within the EU will involve a complaint to the [relevant body] of that member state as the flight is departing from an airport outside of Ireland," he stated.

He added that information on what to do if a person wanted to lodge a complaint about a flight was available at their website www.flightrights.ie.