The Duke of Cambridge met veterans of the Second World War as he attended an air display to mark the 60th anniversary of the Battle of Britain Memorial Flight.
William is patron of the Flight, which was formed to honour the iconic planes involved in the Battle of Britain.
The Duke arrived at RAF Coningsby in Lincolnshire by helicopter then spoke to veterans before watching an air display of a Lancaster, three Spitfires and a Hurricane flown by serving RAF aircrew.
Veteran Rusty Waughman, 94, who was a Lancaster pilot from 1943 to 1944, spoke to William.
"He was so easy to talk to, so pleasant," he said.
"Being here brings back so many memories."
He said he was 20 years old when he first piloted a Lancaster bomber, and it was a "privilege" to fly.
But he added that 101 Squadron, which performed radio counter measure duties, had a 60% attrition rate, and added: "To survive, we were very fortunate."
The Battle of Britain Memorial Flight (BBMF) was formed on July 11 1957 by Group Captain Peter Thompson, a former Battle of Britain Hurricane pilot.
He set about collecting and preserving examples of the main aircraft involved in the conflict to honour the RAF's defence of the UK against German attacks at the end of 1940, having realised many were falling out of service.
Group Captain Thompson began the flight with a Hurricane and three photo reconnaissance Spitfires.
The BBMF now has 12 historic aircraft, including a Lancaster, a Dakota, six Spitfires, two Hurricanes, and two Chipmunks, which are used for training.
It has displayed at or flown past thousands of events as a living tribute to those who have served in the RAF.
William, who completed his service with the RAF Search and Rescue Force at RAF Valley, Anglesey, is Honorary Air Commandant of RAF Coninsgby.
Maurice Snowball, 95, who served as a Lancaster flight engineer, also spoke to the Duke.
"He sat on the chair next to me and I said I hope you don't mind sitting there as I can only hear with my right ear, so you're on my right side," said Mr Snowball.
"He said that's all right. He asked me how I got on flying and I said I enjoyed it, it was a good crew that we were in.
"I said the best memory I've got was the Operation Manna food drops and I told him about that."
As part of the humanitarian operation, known as Food from Heaven, Allied bomber crews dropped food supplies to relieve a famine in parts of German-occupied Holland, including Rotterdam.
The Duke joined veterans as Group Captain Mike Baulkwill and Squadron Leader Andrew Millikin gave speeches on the significance of the anniversary.
The event, which was also attended by Air Cadets ambassador Carol Vorderman, concluded with a group photograph in front of a Lancaster on the airfield.