With World War II looming the Air Ministry needed to expand aircraft engine production. A shadow factory was built in Liverpool however test and repair facilities were required nearer to home.
Just down the A4 towards London was a large structure that had lost its purpose in wartime. Opened in 1937 the Earls Court exhibition centre was a modern new open building which Napiers took over in 1939. The arena was converted into a wartime engine overhaul and engine rebuild centre for the Sabre engine.