Hawker Siddeley Aircraft was formed in 1935 as a result of the purchase by Hawker Aircraft of the companies of J. D. Siddeley, the automotive and engine builder Armstrong Siddeley and the aircraft manufacturer Armstrong Whitworth Aircraft.
Hawker Siddeley Aircraft naceu no ano 1935 como resultado da compra por parte de Hawker Aircraft das compañías de John Davenport Siddeley, a fabricante de coches e motores Armstrong Siddeley e a de avións Armstrong Whitworth Aircraft.