The King of the Netherlands has worked a secret side-job for the past 21 years.
It turns out King Willem-Alexander was frequently flying KLM Cityhopper planes for more than two decades.
In an interview with national newspaper De Telegraaf published yesterday, the King revealed he had ended his role as a regular "guest pilot" on the European airline's fleet of Fokker 70 planes. Before that, he co-piloted Dutch carrier Martinair.
Willem-Alexander will now retrain to fly Boeing 737s as the Fokkers are being phased out of service, he said.
According to De Telegraaf, the King flew KLM passenger flights twice a month, and despite his high ranking title outside the airport, he always flew as co-pilot as a guest flier.
Willem-Alexander said flying was the ultimate form of de-stressing as King to 17m Dutch citizens.
"You have an aircraft, passengers and crew. You have responsibility for them," he told De Telegraaf.
"You can't take your problems from the ground into the skies. You can completely disengage and concentrate on something else. That, for me, is the most relaxing part of flying."