LONDON, UNITED KINGDOM - DECEMBER 02: The Duke Of Edinburgh attends the opening of the 'First World War In The Air' exhibition at the RAF museum in Hendon on December 02, 2014 in London, England. (Photo by Eddie Mulholland - WPA Pool /Getty Images)
LONDON, UNITED KINGDOM - DECEMBER 02: The Duke Of Edinburgh attends the opening of the 'First World War In The Air' exhibition at the RAF museum in Hendon on December 02, 2014 in London, England. (Photo by Eddie Mulholland - WPA Pool /Getty Images)