The award which Leslie Manser collected was the  highest award of which  honours system
Leslie Manser Leslie Thomas Manser VC (11 May 1922 – 31 May 1942) was a British bomber pilot and recipient of the Victoria Cross, which was awarded posthumously following an attack on the German city of Cologne.
Air Efficiency Award The Air Efficiency Award, post-nominal letters AE for officers, was instituted in 1942. It could be awarded after ten years of meritorious service to part-time officers, airmen and airwomen in the Auxiliary and Volunteer Air Forces of the United Kingdom and the Territorial Air Forces and Air Force Reserves of the Dominions, the Indian Empire, Burma, the Colonies and Protectorates.