Johns undertook his initial flying training at the short lived airfield at Coley Park in Reading, flying the Farman MF.11 Shorthorn aircraft. He was then posted to No.25 Flying Training School at Thetford in Norfolk, closer to where his wife and son lived. On 1 April 1918, Johns was appointed flying instructor at Marske-by-the-Sea in Cleveland. Aircraft were very unreliable in those days and he promptly wrote off three planes in three days due to engine failure - crashing into the sea, then the sand, and then through a fellow officer’s back door. Later, he was caught in fog over the Tees, missed Hartlepool and narrowly escaped flying into a cliff. Shooting one’s own propeller off with the synchronised forward-mounted machine-gun was an accident, but it happened to Johns twice. The Commanding Officer at Marske was a Major Champion, known as 'Gimlet', a name used later by Johns for the hero of a series of stories. Johns served as a flying instructor until August 1918 when he transferred to the Western Front.
He only performed six weeks of active duty as a bomber pilot before being shot down and taken prisoner on 16 September; he remained imprisoned until the end of the war.
After the war, Johns remained in the RAF and served a year (1924-25) in Newcastle, while living with Doris (Dol) Leigh, his devoted companion, on the coast at Whitley Bay.
He stayed with the Royal Air Force until 1927, retiring with the rank of Flying Officer. As a recruiting officer, Johns initially rejected T. E. Lawrence (of Arabia) as an RAF recruit for obviously giving a false name, but was later ordered to accept him.
After leaving the RAF, Johns became a newspaper air correspondent, as well as editing and illustrating books about flying. At the request of John Hammond Ltd., he created the magazine Popular Flying which first appeared in March 1932. It was in the pages of Popular Flying that Biggles first appeared.
The first Biggles book, The Camels are Coming, was published in August 1932. Unique among children’s writers of the time, from 1935 Johns employed a working-class character as an equal member of the Biggles team - "Ginger" Habblethwaite, later Hebblethwaite, the son of a Northumberland miner (we never learn his real Christian name, and he proclaims himself a Yorkshireman once or twice).
At first, the Biggles stories were credited to "William Earle", but later Johns adopted the more familiar byline "Capt. W. E. Johns". The rank was self-awarded; his actual rank of RAF Flying Officer was equivalent to an army Lieutenant.
Johns edited Popular Flying and later its weekly sister Flying until the beginning of 1939. He was removed because of pressure from the government as he opposed the policy of "appeasement". At that time, Johns also wrote novels, short stories and magazine articles.
During the Second World War, the propaganda value of Johns' books was seen by the Air Ministry.
Johns continued writing Biggles until his death in 1968. In all, nearly a hundred Biggles books were published.
Other less-famous characters created by W. E. Johns include commando Captain Lorrington "Gimlet" King; aviatrix Joan "Worrals" Worralson (essentially a female Biggles, created at the request of the Air Ministry to inspire more young women to join the Women's Auxiliary Air Force); and pioneering astronaut (ex-RAF, naturally) Group Captain Timothy "Tiger" Clinton, who first rocketed into space in 1954.
By Jove, Biggles!, a biography of Johns was published in 1981, written by Peter Berresford Ellis and Piers Williams.