The Duke of Cambridge has returned to familiar territory today when he met members of the Royal Air Force at RAF Coningsby in Lincolnshire.
William made his fourth official visit to 29 Squadron, where he is Honorary Air Commandant, to meet those who work from there.
In 2008, the Royal spent a week at the base to learn what RAF life was like, including having a ride in a Typhoon.
Coningsby is now home to a new engagement centre for the local community - the first of its kind at an RAF facility.
His Royal Highness met local school children as they took part in an exercise to design a parachute mechanism to drop an egg from a height.
It is all part of a campaign called STEM, (Science, Technology, Engineering and Maths) to show how physics plays a part in RAF operations.
The Duke, who for many years flew helicopters at RAF Valley, also met trainee typhoon pilots who will be the future of the RAF.
They are part of the Typhoon Operational Conversion Unit - training pilot and ground crews how to use the fast jet.
William spent almost 40 minutes speaking to current pilots and ground crews and those undergoing training on the Typhoon - and also took the opportunity to sit in a Typhoon's cockpit - a decade after he flew in the back seat of the fighter from the same station.
The Lincolnshire base is one of two which provide 24 hour-a-day, seven-days-a-week fighter cover to intercept threats ranging from Russian bombers to commercial airliners suspected to have been hijacked.
The other is RAF Lossiemouth in Scotland.
Wearing a suit, the duke spent ten minutes in the cockpit discussing the controls and the aircraft's capabilities with Wing Commander Andy Chisholm