The second-in-line to the British throne took off in the Chinook just after getting his RAF wings at RAF Cranwell, Lincs. He made a quick pit stop to pick up brother Harry at Woolwich Barracks, South East London, before flying to Bembridge Airport on the Isle of Wight. The trip meant that William not only completed his training, but also got more than five extra hours in the bar at the party. It took the princes just an hour and 20 minutes to reach the bash, instead of the seven hours that would have taken them by road and ferry.
"He would have had to fly over London and open water anyway. This was a welcome coincidence," The Sun quoted a source, as saying.
An RAF spokesman said that the 250-mile flight was a "legitimate training sortie which tested his new skills".