Thousands of people have gathered outside Buckingham Palace to watch a flypast of aircraft to mark the centenary of the Royal Air Force.
Almost 100 planes representing the RAF over the years flew over The Mall following a parade by personnel.
The Queen and other members of the Royal Family saw the display - which included the new F-35 fighter and Spitfires - from the palace balcony.
Earlier they marked the centenary at a special service in Westminster Abbey.
The service began what the head of the RAF said would be a "tremendous" day of events to mark its 100 years.
Three F-35 Lightning stealth fighters were involved in the flypast and 22 Typhoons spelt out 100 as they flew over the palace.
Nine helicopters led the armada, while the Red Arrows brought up the rear.
The aircraft assembled in holding patterns off the coast of East Anglia before merging near Ipswich and flying down the A12 corridor to London.
According to the Met Police, an estimated 65,000 to 70,000 people gathered on The Mall to watch the parade and flypast, with roads in central London being closed until 17:00 BST.
Surrounded by other members of the Royal Family, the Queen presented a new Queen's Colour to the RAF in the forecourt of Buckingham Palace before moving to the balcony.
In a brief speech, she congratulated the RAF for a "remarkable contribution to defence" over the last 100 years, saying "tenacity, skill and gallantry" had been its hallmarks.
She added: "I remember the Battle of Britain being fought over the skies above us and we shall never forget the courage and sacrifice of that time."
The Royal Flying Corps and the Royal Naval Air Service merged to create the RAF on 1 April 1918 - the world's first independent air force.
In his address at Westminster Abbey, the Archbishop of Canterbury, the Most Reverend Justin Welby, said the RAF had played a "decisive factor in saving this country's independence, its democracy and its freedom; its hope of civilisation and its contribution to humanity for the future".
He added: "It is also right to remember with sorrow and again profound thanksgiving the scores of thousands who have given their lives in service as part of the RAF."
The Queen, who did not attend Prince Louis' christening on Monday, was at the service along with the Prince of Wales and the Duchess of Cornwall, the Duke of York, the Earl and Countess of Wessex, the Duke and Duchess of Cambridge and the Duke and Duchess of Sussex.
Retired and serving members of the RAF were also there, along with the Chief of the Defence Staff, General Sir Nick Carter, and politicians including Prime Minister Theresa May, Defence Secretary Gavin Williamson and Labour leader Jeremy Corbyn.
Princes William wore the No 1 uniform of the Royal Air Force, and his RAF wings, in recognition that he is a qualified RAF pilot.
The Duke of Sussex's uniform carried RAF Regiment shoulder flashes in recognition of the home of the RAF, Honington, and his role as Honorary Air Commandant of the base.