While it is no secret that Willem-Alexander is a qualified pilot who sometimes flew KLM passenger flights, it was not previously clear how frequently it happened. Willem-Alexander said he is rarely recognised by passengers, especially since security was tightened on board planes in the aftermath of the 9/11 attacks. “Before September 11, the cockpit door was open. People regularly came to have a look and thought it was nice or surprising that I was sitting there,” he said, adding that very few people recognise him as he walks through Amsterdam’s Schiphol Airport in KLM uniform and cap.