Less than a third of Welsh holidaymakers used Cardiff Airport for their trips in 2011, with as many or more travelling to one of London’s four airports.
The figures for 2011, the most recent year available, show 1.2 million Welsh air passengers used the Rhoose terminal, according to the Civil Aviation Authority (CAA). This compares to 1.24 million people from Wales using Heathrow, Gatwick, Stansted and Luton that year.
A further 759,000 flew from Manchester Airport, 198,000 from Birmingham Airport and 15,000 from East Midlands Airport. Figures for Liverpool and Bristol airports were not provided.
The most popular single airport for Welsh travellers outside Wales was Heathrow (810,000 passengers).
It comes as new CAA figures also show the number of passengers using Cardiff Airport was up 8.7% in May compared to a year before. However, the provisional figures also showed that the number of passengers over the 12 months since last June was just 995,500 – a fall of 10.6% over the previous 12 months.
Aviation expert Martin Evans, a visiting fellow at the University of South Wales, said he was expecting a modest return to growth this year at Cardiff, “based on a good summer”.
He said: “Passengers are drawn by two things, they’ll go where the flights and frequencies are and where the flights are cheapest.”
Passengers are currently attracted to the number of low-cost flights to a larger range of destinations at Bristol and flights to worldwide destinations at London’s airports, he added.
“The challenge for Cardiff Airport is to attract airlines which are going to retain some of these passengers in Wales and make better use of Cardiff Airport,” he said.
“We have a situation where Cardiff could handle far more passengers who are travelling out of South Wales to use airports in congested areas.
“It’s not good for passengers and it’s bad for the economy of Wales. Passengers using airports in England are exporting jobs out of Wales.”
Mr Evans said the situation was not an easy one to turn around “because out of the passengers that are leaving Wales you have to identify a very popular destination that would make it attractive enough for an airline to offer that service from Cardiff”.
Earlier this year, Cardiff Airport was bought by the Welsh Government for £52m.
Mr Evans added: “The key to increasing passengers numbers to make the airport attractive to airlines is to reduce costs by devolving air passenger duty (APD) to the Welsh Government and for the Welsh Government to set it to zero.”
Putting in sufficient surface access to make it quick and easy for passengers to use Cardiff is also necessary, he said.
Earlier this month the Welsh Conservatives proposed the appointment of an airlines director to attract new carriers, improved transport links and the devolution of air passenger duty to lower rates and improve competitiveness.
Andrew RT Davies, the leader of the Welsh Conservatives in the Assembly, said yesterday: “The issue of declining passenger numbers has been a problem for some time now and it is concerning that many forecasters are now suggesting that figures could fall below a million by the end of this year.
“There is a danger, of course, that we can focus too heavily on the Welsh passengers flying out of local airports when more also needs to be done to attract visitors to Wales, and in particular to Cardiff Airport.”
“Whilst there has been some good news recently, with Thomas Cook increasing their capacity and Vueling expanding their winter schedule, sadly the perennial issue of transport links to and from the airport remains an ever-present block on its development.”
“Furthermore, we need to be doing more to attract new airlines and to develop new routes. The capacity is there and sadly years of under investment have led the airport to where we are today.”
An airport spokeswoman said: “We have already announced increases for summer as well as winter 2013 and we continue to work hard with current and potential new airlines to put more capacity in place.”
“We are confident we shall continue to make progress and remain focussed on delivering more capacity and an improved route network for the people of Wales.”
Other figures released today show that freight volumes at Cardiff airport were sharply down last year compared to the year before.
The figures show that 66 tonnes of freight were handled at the airport in 2012, compared to 377 in 2011.
However, freight volumes through Cardiff are highly volatile, with sharp swings from year to year over the last four years.
Mr Evans said: “Because there are no wide body aircraft using Cardiff suitable for carrying freight as bellyload, freight is entirely dependent on integrated cargo carriers such Federal Express.
“If one of those were to introduce a freight service into Cardiff it would increase the amount of freight through Cardiff significantly.”
He added: “The key to freight movement is getting services to international destinations with wide body aircraft.
“Most cargo in South Wales leaves Wales on the back of a lorry and goes to Heathrow. It would be far better for Wales if we could attract those long haul services that would attract freight carriers.”
Cardiff Airport were approached but declined to comment.