Ledger was commissioned into the
Queen's Own Royal West Kent Regiment on 29 May 1918. He was deployed to
France for service in the
First World War. After transferring to the RAF as an observer officer in 1919, he became officer commanding,
No. 40 Squadron in August 1935 and then served in the
Second World War as senior air officer, HQ Air Forces in
India from July 1940, as Deputy Director of Ground Defence from March 1942 and as Director of Ground Defence from later that year. ==References==