The sculpture depicts seven air crew members with the inscription, "We remember those of all countries who died in 1939-1945".
Other royals including Prince Charles and the Duchess of Cornwall, were in attendance alongside the Duke of York, Earl and Countess of Wessex, the Duke and Duchess of Gloucester and Prince and Princess Michael of Kent.
A Lancaster bomber aeroplane performed a fly-past during the ceremony and dropped red poppies on those below, who also included some survivors from the conflict.
The Queen and Prince Philip met some of the Bomber Command veterans as well as architect Liam O'Connor and sculptor Philip Jackson.
Following the ceremony, most of the royal party departed to have lunch at the RAF Club in Piccadilly. Prince Charles and the Duchess of Cornwall remained behind to speak with Bomber Command veterans.
We will remember them