Which airline has the worst punctuality record?
Wizz Air has the worst punctuality record of the busiest airlines operating from UK airports, an investigation has found.
The Hungarian carrier's UK departures were an average of 23 minutes late in 2017, according to Press Association analysis of Civil Aviation Authority (CAA) data.
Norwegian Air Shuttle has the second worst performance, followed by Vueling Airlines, Thomas Cook Airlines and BMI Regional.
The ranking features the 44 airlines with at least 2,000 scheduled flights from UK airports last year.
Average delay figures take into account every flight that operated, including those that were on time. Cancelled services are excluded from the CAA data.
Scandinavian Airlines is the most punctual, with aircraft typically taking off just seven minutes behind schedule.
Aer Lingus has the second best record, followed by Air France, Alitalia and Delta Airlines.
The average delay across all flights was 15 minutes.
A spokeswoman for Wizz Air said: "A number of issues specific to the UK, including airport infrastructure, airspace congestion and slot restrictions contribute to a significantly worse on-time performance of our UK routes compared to the rest of our network."
She noted that disruption was caused by "particularly severe winter weather" last year and added that the airline is taking measures to improve its punctuality, such as basing eight aircraft in the UK to reduce its exposure to inbound delays.
Norwegian Air Shuttle's UK flights mainly consist of short-haul services from London Gatwick, Manchester and Edinburgh. Its average delay of 22 minutes does not take into account the majority of Norwegian's long-haul flights from UK airports, which are operated by a British subsidiary.
A Norwegian spokesman said frequent air traffic control (ATC) strikes across Europe and adverse weather "invariably impact punctuality" and are beyond the control of airlines.
He went on: "We do everything possible to ensure that flights operate to allow passengers to reach their destination as soon as possible.
"Norwegian is committed to keep improving punctuality, and where factors are within our direct control we have introduced new measures to continue delivering a smooth, efficient experience for our passengers."
The CAA said punctuality "clearly matters to airline passengers" and it publishes the performance of carriers to allow people to "make informed choices about which airline to fly with".
Dale Keller, chief executive of airline association BAR UK, said delays are "extremely costly" to carriers.
He added that airlines are "fully engaged" with governments, ATC providers and airports to minimise the causes of disruption which are outside their own control.
Passengers on delayed flights from UK airports are entitled to assistance and compensation depending on the cause and length of the disruption.
When flights are delayed for more than two hours, airlines have to provide free access to phone calls or emails, meals and refreshments, as well as hotel accommodation if an overnight stay is required.
Passengers can also claim compensation when flights are delayed by more than three hours unless there are "extraordinary circumstances" such as severe weather or a security alert.
Payouts range from 250 euro (£223) to 600 euro (£535) depending on the length of the flight and how long it was delayed.
Editor of magazine Which? Travel, Rory Boland, advised delayed passengers to "make sure you make a claim for the compensation that you are entitled to".
He added: "Airlines now need to do the right thing and introduce automatic compensation. Passengers should not have to jump through hoops to claim back the money they are owed."