The Queen was joined by Harry, Meghan, William and Kate at Westminster Abbey as part of a day-long celebration of the Royal Air Force as it marks its centenary year.
Other prominent members of the royal family were also on hand to commemorate the momentous occasion, including the Duke and Duchess of Cornwall.
It was 100 years ago on April 1 1918 that the Royal Flying Corps and the Royal Naval Air Service merged to create the RAF – the world’s first independent air service.
Following the service at Westminster Abbey, the Queen will present a new Queen’s Colour to the RAF along with her son Prince Charles in the forecourt of Buckingham Palace, before she makes a brief speech.
The Duke and Duchess of Cambridge and the Duke and Duchess of Sussex arrive at a service at Westminster Abbey today
Queen Elizabeth II attends a service at Westminster Abbey, London, to mark the centenary of the Royal Air Force today
The Queen was joined by family members including the Prince of Wales and the Duchess of Cornwall, the Duke of Cambridge and the Duke and Duchess of Sussex
Prominent members of the royal family have arrived at Westminster Abbey as part of a day-long celebration of the Royal Air Force as it celebrates its centenary year
Prince Harry, Meghan and Prince William are among the royals who have arrived at Westminster Abbey for a service to mark the RAF centenary
The Duchess of Cornwall was the picture of elegance in a white dress, pearl necklace and a cream hat for the occasion
The royals will then appear on the balcony of the Queen’s London residence to view a flypast of up to 100 RAF aircraft, a parade of more than 1,000 personnel, and a feu de joie.
Air-Vice Marshal Gerry Mayhew, the air officer commanding No 1 group and the senior responsible officer for the flypast, said the day is the ‘centrepiece’ of the RAF’s 100th year.
‘It is the high point for the capital, Her Majesty the Queen and the royal family,’ he told the Press Association.
‘And it is a great opportunity to look back and really celebrate our past, but to look forward is a really important thing for us as we look to the next 100 years.’
He described being at the forefront of the flypast as a ‘great honour’, and said he hopes the Queen and royal family will see ‘exactly what they can do’ for the monarch.
Asked what message a 100-aircraft flypast may send to Britain’s adversaries and the world, he said: ‘It demonstrates we are a competent, professional and capable air force that has a credible, very credible, set of capabilities.’
Charles, Camilla, William, Harry and Meghan will also meet veterans, personnel, charity representatives and those from the civil service in a reception after the spectacle.
Princess Anne and her husband Vice Admiral Sir Timothy Laurence arrived for the RAF centenary service on Tuesday
The Duke of Sussex gallantly took his wife’s arm as they arrived for the service at Westminster Abbey on Tuesday
Sophie, Countess of Wessex, left, and the Duchess of Cambridge, right, both opted for dresses in soft colours
The royals will then appear on the balcony of the Queen’s London residence to view a flypast of up to 100 RAF aircraft, a parade of more than 1,000 personnel, and a feu de joie
Prince Harry shared a joke with his uncle Prince Andrew, who was seated on the other side of the Duchess of Sussex
The newlyweds, who tied the knot in May, looked in excellent spirits as they took their seats ahead of the service
Just 15 years after the first-ever powered flight undertaken by the Wright brothers, the decision to create the RAF was made after the War Cabinet inquiry criticised the poor organisation of Britain’s air forces.
Those recognised as the founders of the RAF include Lieutenant General Sir David Henderson and Lord Hugh Trenchard – the first chief of the air staff.
The flypast is set to feature aircraft including Puma and Chinook helicopters, a Lancaster, Spitfires, Hurricanes, the A400M Atlas, Tornados, Typhoons and the F-35 stealth fighter jets.
Drawing the spectacle to a close will be the Red Arrows, who in traditional aerobatic style will stream red, white and blue smoke down the length of The Mall.
The officer commanding the Red Arrows, Wing Commander Andrew Keith, who took the helm in August, said it is an incredible year to be leading them.
‘We will put the red, white and blue on at the end of the flypast, which I think is a fitting way to end it, which is great,’ he said.
During the flypast, he said he will be flying in the formation in the back seat of the team leader’s jet, ‘getting a few photos’.
‘It is going to be business as usual for us – and hopefully clocking over that 100th aircraft,’ he said when asked if they will be doing anything different on the day.