EASYJET has said last month's drone disruption at Gatwick was a "wake-up call" to airports after it cost the airline £15 million and affected 82,000 customers.
The low cost carrier said it racked up £10 million in passenger compensation costs and £5 million in lost revenues after more than 400 of its flights were cancelled when the drone sightings brought Gatwick to a standstill just before Christmas.
EasyJet chief executive Johan Lundgren said he was "disappointed" the airport took so long to resolve the situation and reopen the runways.
But he said it was a "criminal act and illegal activity".
"You can't always protect yourself from that, but it's a wake-up call and airports will be better prepared going forward," he added.
The drone scare saw flights at Gatwick suspended on December 19 at the height of the pre-Christmas travel rush, with the airport not full reopened until December 21.
The three days of chaos saw more than 1,000 flights grounded and some 140,000 passengers affected.
Mr Lundgren said easyJet "did everything we could to help our customers affected by the incident".
"I am proud of the way our teams worked around the clock to mitigate the impact of the incident and looked after affected customers," he said.
In its first-quarter update, easyJet said its capacity rose 18.2 per cent to 24.1 million, which was lower than expected, due in part to the drone disruption.
Total revenues in the three months to December 31 lifted 13.7 per cent to £1.3 billion, while passenger revenues rose 12.2 per cent to £1.03 billion.
Passenger numbers in the quarter increased by 15.1 per cent to 21.6 million.
Shares in the FTSE 100-listed group rose 7 per cent after the update.
EasyJet said it was "well prepared" for Brexit and had not seen an impact on passenger bookings ahead of March 29.
It added: "Both the EU and the UK have committed to ensure that flights between the UK and EU will continue in the event of a no-deal Brexit."
Mr Lundgren said: "For the first half of 2019, booking levels currently remain encouraging despite the lack of certainty around Brexit for our customers."
Overall the group said full-year expectations are "broadly" in line with market forecasts, though it said it expects a loss this year in its Berlin business, where it took over of some of Air Berlin's operation when the carrier went bust.
It sees easyJet largely shrug off the woes suffered by rival Ryanair, which warned over profits last week as it counts the cost of lower-than-expected airfares over winter amid over capacity in Europe.
Nicholas Hyett, equity analyst at Hargreaves Lansdown, said: "The drone disruption at Gatwick in December means these results aren't quite what easyJet was hoping for at the start of the year, but it hasn't blown things too far off course."
Fortunately Brexit disruption seems to be minimal so far, and while meeting full year expectations may be a bit more of a stretch from here, they're still very achievable," he added
