The survey questioned passengers arriving in Scotland

The full economic impact of direct flights to and from the airport has been calculated for the first time for Scottish Enterprise Ayrshire.

The rapid growth in passenger numbers at Prestwick is said to be mainly down to the expansion of the budget airline Ryanair, which now flies to nine destinations from its Ayrshire base.

This year alone, the airline expects to fly more than a million people through Prestwick.

For the first time, the economic impact of those passengers has been calculated by a firm of economic development consultants.

'Success factor'

According to the report, Ryanair's inbound passengers stayed 2.4 million nights in Scotland during 2002-2003, spending up to �89m.

The average duration of visits was just under eight nights, with passengers spending just under 280,000 nights in Ayrshire.

Scottish Enterprise Ayrshire's chief executive Evelyn McCann welcomed the survey's findings.

She said: "The presence of budget airlines like Ryanair at Prestwick is a key economic success factor both at a local and at a national level.

Visitors spent an average of �215 a visit

"This survey has thrown up some fascinating results, and it is gratifying to see that Ryanair's services from Glasgow Prestwick are responsible for contributing so much to Scotland and up to �18m to the local economy."

Michael Cawley, chief operating officer and deputy chief executive of Ryanair, said: "This survey has confirmed our belief, and we are delighted to be such an important factor in the growth and development of Scottish tourism."

The survey team questioned 831 passengers between August 2002 and July 2003 as part of the research.

It found that visitors spend an average of �215 each per trip in the local economy and that most come here for a holiday or to visit friends and relatives.