The Hercules: The Other Engine That Helped Win the War

The Bristol Hercules was a 14-cylinder sleeve valve radial engine designed by Sir Roy Fedden and produced from 1939 by BAC. It powered Bristol’s own Beaufighter but was more commonly used on bombers. From the 1375 hp Hercules I to the 1735 hp Hercules XVII produced late in the war, the variants powered the Avro Lancaster B.II, the Handley Page Halifax, the Short Stirling, the Vickers Wellesley and the Vickers Wellington, among others. The sleeve valve engine was an efficient configuration t...