Frank Inglis Air Vice - Marshal Francis " Frank " Frederic Inglis CB , CBE ( 22 June 1899 – 25 September 1969 ) was a British officer in the Royal Air Force who became the head of RAF Intelligence Staff during the Second World War , reporting to Winston Churchill . In 1942 he was sent to America by Churchill , where he successfully persuaded President Franklin D . Roosevelt to direct the main American war effort against Germany rather than Japan . Family and early life . Inglis was the fourth child of Alfred Markham Inglis ( 1856 – 1919 ) ( a banker who had previously played cricket for Kent ) and Ernestine ( Nina ) May Pigou ( 1863 – 1941 ) . His grandparents were Major - General Sir John Eardley Inglis and Lady Julia Inglis , who had survived the Siege of Lucknow , and Francis Pigou , the Dean of Bristol . His sister , Mildred Inglis ( 1897 – 1979 ) , was married to ( Sir ) Victor Goddard ( 1897 – 1987 ) who was a senior commander in the Royal Air Force during the Second World War . Inglis was educated at Royal Military College , Sandhurst , and graduated in 1918 , from where he was commissioned into the Duke of Cornwall ' s Light Infantry . In the summer of 1927 , he married Vera Helen " Midge " Turner ( b . 1906 ) . They had three daughters : His cousin , John Inglis was head of Naval Intelligence from 1954 to 1960 . Royal Air Force career . After graduating from Sandhurst , Inglis spent three years with the Duke of Cornwall ' s Light Infantry , reaching the rank of lieutenant , until July 1921 , when he was seconded to the Royal Air Force as a flying officer . After 18 months at No . 5 Flying Training School , in December 1922 he joined No . 84 Squadron as a pilot , based in Iraq , flying DH . 9As . In April 1925 , he was on the staff of the RAF depot in Egypt , before joining No . 208 Squadron in January 1926 . By now , Inglis had resigned his commission in the Duke of Cornwall ' s Light Infantry and had been appointed to a permanent commission in the rank of flying officer . On 1 July 1927 , Inglis was promoted to flight lieutenant ; he was immediately placed on half pay until the end of July , having recently got married . On his return to active service , Inglis joined the staff at No 4 Apprentice ' s Wing , RAF Cranwell . In April 1931 , he transferred to the staff of the RAF College , until returning to Iraq in December 1933 as a member of the air staff , HQ Iraq Command . In January 1936 , he returned to England , and attended the RAF Staff College at Andover . He was promoted to squadron leader on 1 April 1936 and to Wing Commander on 1 March 1939 . Intelligence career . In January 1937 , he was appointed to the staff of the deputy directorate of Intelligence , and promoted to deputy director of intelligence ( 3 ) ( DDI3 ) in 1940 . In this role , he was head of the German branch of air intelligence . He was promoted to the rank of group captain in September 1941 and to ( acting ) air commodore in March 1942 . In March 1942 , he was promoted to director of intelligence ( operations ) , reporting direct to the prime minister , Winston Churchill . Following the entry of the United States into the Second World War , Churchill sent Inglis to see President Roosevelt to persuade him to direct the United States war effort primarily against the German air force in Europe . Inglis stayed in the White House and held two meetings with Roosevelt , eventually persuading the president to go against his own advisors and agree to the British viewpoint , that the major American war effort must be directed towards the defeat of Germany first . According to Inglis ' s brother - in - law , Air Marshal Sir Victor Goddard , No other war decision by America was more significant for Europe and the World than that one . It is to be attributed to the clear trustworthiness of Frank Inglis that his vital , single - handed mission was successful , and it is to be attributed to his modesty that his part in that happening seems never to have come to the notice of historians . In October 1942 , Inglis was promoted to assistant chief of the air staff ( intelligence ) , with the military rank of ( acting ) air vice - marshal , succeeding Air Vice - Marshal Charles Medhurst , thus making him head of Air Intelligence . Later career . At the end of the war , in August 1945 , he was appointed air officer commanding , No . 23 Group , Flying Training Command ( with Air Vice - Marshal Sir Thomas Elmhirst succeeding him at RAF Intelligence ) . On 20 January 1947 , he was appointed senior air staff officer , HQ Air Command Far East and on 20 October 1949 as senior air staff officer , HQ Flying Training Command . He reached the full rank of air vice - marshal on 1 July 1947 . He retired at his own request on 29 March 1952 . Honours . Air Vice - Marshal Inglis was appointed Commander of the Order of the British Empire ( CBE ) on 8 June 1944 and Companion of The Most Honourable Order of the Bath ( CB ) on 1 January 1946 . In October 1945 , he was conferred with the honour of Commander of the United States Legion of Merit for " exceptionally meritorious conduct in the performance of outstanding service " . In 1946 , he was also conferred with the honour of Grand Officer of the Order of the Phoenix by the King of Greece . In July 1957 , he was appointed Deputy Lieutenant of the county of Kent .