In Biggles and the Black Mask, Millham was a small prewar aerodrome in Suffolk which had been used during the war by the American forces as a training airfield. After the war, it was used for a time as a practice emergency landing ground for pilot trainees flying piston engine aircraft but was later abandoned when it proved too small for modern jets. The aerodrome was near the country house residence of Cedric Adrian Fortescue. When Fortescue devised a plan to run a smuggling operation using aircraft, he either bought or leased Millham and employed ex-R.A.F. pilot Roderick Canson to run an air charter company to be based there.
Millham is a fictional location.