Edinburgh Airport MD's departure is a shock after less than two years in the job

Mr Dewar, 44, the airport's managing director, plans to leave in late summer to become chief executive officer at Bahrain Airport Company, which is in the process of being moved away from government control.

He said his decision to leave Edinburgh so quickly – he moved from Glasgow Airport in July 2008 – had not originally been part of his plan.

He said: "It's a lot sooner than I thought it would be. My only real thinking before this opportunity came up was that I'd definitely want to go overseas after this experience. I thought that would probably be two or three years from now, but this very unique opportunity has come up."

Family reasons also played a part in his decision, with his two teenage daughters at the right age to change schools.

The airport is in the middle of a 40 million terminal extension project, and court wrangles continue to decide whether the Competition Commission can force BAA to sell off either Glasgow or Edinburgh airport.

He said: "Obviously the whole aviation industry has suffered a number of challenges, with the economic downturn, the strike has been unhelpful, and the ash cloud has been uniquely difficult, but we were the only growing airport in the UK last year.

"We've done that by working closely with two key sorts of partners, the airlines themselves, but also the city, and I think the city has come through the economic downturn really strongly."

Mr Dewar would not be drawn on the likelihood of the airport being chosen for sale, should the courts give the go-ahead. He said: "I genuinely don't know. I think that's a matter for the shareholders and will be hugely influenced by timing.

"Edinburgh's in the middle of a 40m investment to deliver new retail facilities and the space that we need, and I think that stands us in great stead to be handling 13 million passengers."

His successor will face fresh challenges, not least the scrapping of plans for a third runway at Heathrow. Mr Dewar said: "It's very disappointing that we've had that decision made.

"In terms of Scottish airports, it's particularly worrying about losing future capacity connections to Heathrow, which is our most important hub airport for connections to the rest of the world."

BAA chief executive Colin Matthews said: "Gordon Dewar has made a substantial contribution to Edinburgh Airport, and will be leaving a healthy airport that is performing well in difficult circumstances.

"We will be looking to appoint somebody with the drive and ambition to build on the positive momentum created in recent months and wish Gordon well as he takes up his new role."