The East Anglia air ambulance pilot came to the rescue of a British man who initially had no idea it was the future King of England rescuing him.
The Duke of Cambridge, who typically stays in the cockpit, assisted the paramedics by comforting and stabilizing tree surgeon Jim Schembri after he was knocked unconscious by a tree branch.
According to onlookers, William was the first to jump out of the helicopter and pull Schembri from a stretcher to a waiting ambulance.
Schembri, who is now recovering, told ITV News in an interview that he had no idea the Duke of Cambridge was at his side.
"It wasn't until they were actually loading me into the helicopter and I said, 'Willsy better not be flying this thing,' and he turned around and said, 'Oh, I've been holding your head for the last thirty minutes,' that it clicked," Schembri said.
Schembri said he later told Prince William, "You better come see me later."
The 37-year-old had nothing but praise for William, saying the prince even went to the emergency room with him to make sure Schembri was okay after dislocating his shoulder and hip.