Hawker Tornado HG641 3rd prototype
When it became clear that the Tornado program would be canceled, Sydney Camm proposed using at least one Tornado to assist in developing the new Bristol Centaurus eighteen-cylinder engine, which was under development at Filton. Due to prioritization of other work, significant progress on this idea wasn’t made until April 1940, when an additional prototype was ordered. However, only a new center section was constructed, with other major components sourced from stock at Langley. The resulting aircraft, serial number HG641, was equipped with a Centaurus CE.45 engine rated at 2,210 horsepower and had its maiden flight, piloted by P. G. Lucas, on October 23, 1941.
Initial test flights revealed serious cooling issues, with the engine’s exhaust collector ring positioned forward of the powerplant, resulting in a single exhaust that exited under the port wing. To address this, the exhaust pipes were split and vented under the center section of the aircraft, and the cowling was modified to accommodate these changes. Additionally, the oil cooler intake was extended to the lower edge of the cowling to improve cooling airflow.
HG641 featured a Rotol propeller assembly with a large spinner covering the entire hub. After these modifications, the aircraft’s performance improved significantly, prompting a small order for six more aircraft in early 1942. The revised engine setup allowed the Centaurus Tornado to resume flying in November 1942, achieving a maximum speed of 412 mph (663 km/h) at an altitude of 18,000 feet (5,500 m).
Despite the successful test flights, no further aircraft were built, as the testing of the Centaurus in the Typhoon II demonstrated it to be a superior aircraft. The sole Centaurus-powered Tornado continued as a test bed until August 1944, when it was scrapped.