William Austyn Mair

High Speed Aerodynamics

In 1940 he was posted as an RAF Technical Officer to the Aerodynamics Department of the Royal Aircraft Establishment (RAE) at Farnborough and he remained there until August 1946, working on the changes that occur in the aerodynamics of aircraft as the flight speed approaches the speed of sound. This work made use of a new high speed wind tunnel under construction at Farnborough. Mair played a leading part in bringing this tunnel into operation and in co-operation with others he used it intensively from the end of 1942.

From 1941 to 1946, Mair was engaged in the study of high speed aerodynamics using aircraft in flight. The aircraft used were mostly Spitfires, flown by Wing Commander Wilson, the chief test pilot at Farnborough, who was happy to hold the aircraft in a steep (but never vertical) dive to achieve very high speeds. He was also happy to have the radio removed to leave more room for instrumentation.

Although the main purpose of the research was to investigate the behaviour of aircraft as they approached the speed of sound, Mair also conducted an investigation into the rumour, hushed up at the time, that the tails came off Spitfires if they were flown too fast. This research, conducted rather understandably in a shroud of secrecy, showed that the tails were able to withstand the loading on them, although one surprising result was the discovery that the loading during a dive was predominantly on one side.