Gatwick and Easyjet have been named as having the longest average delays for flights over the previous two summers.
Research carried out by the BBC, based on punctuality figures from the CAA, showed that passengers flying from Gatwick between June and August suffered an average delay of 27 minutes, while those flying Easyjet faced an average hold-up of 24 minutes.
Both Gatwick and Easyjet responded by saying that they had the most European flights in the UK and many delays were “beyond their control”. Easyjet is the biggest airline operating at Gatwick.
Gatwick’s average summer delay compared with a 16-minute delay at Heathrow, 17 minutes per flight at both Manchester and Glasgow, and 18 minutes at Edinburgh and Birmingham.
Easyjet was followed in the average length of delay by Thomas Cook, British Airways, Thomson and Jet2. Aer Lingus had an average delay of only 12 minutes – half that of Easyjet.
"Easyjet operates the largest number of flights of any UK airline, flying over 78 million passengers per year,” said the airline.
“Despite a number of adverse external factors like increasingly congested airspace, particularly in the London area, and record numbers of air traffic control strikes, over the last year, Easyjet has actually reduced the proportion of flights delayed by more than three hours.
"We work hard to minimise disruption and fully comply with all relevant regulations."
Gatwick said it operated “the world's busiest and most efficient single runway airport”. But flights had been affected by external factors such as air traffic controller strikes in Europe, bad weather and “congested” airspace around London and parts of Europe.