Rolls-Royce aircraft piston engines test stand. The Buzzard was an enlargement of the Kestrel of Condor size, developed in its most extreme form into the Rolls-Royce R racing engine used for the Schneider Trophy competition. The Vulture of 1939 was essentially two Peregrines on a common crankshaft in an X-24 configuration, both of these types being deemed unsuccessful. The Rolls-Royce Merlin, and later the development of the Buzzard, the Rolls-Royce Griffon were the two most successful designs for Rolls-Royce to serve in the Second World War, the Merlin powering RAF fighters the Hawker Hurricane, Supermarine Spitfire, fighter/bomber de Havilland Mosquito, Lancaster and Halifax heavy
Rolls-Royce Welland Minister of Aircraft Production and the Boards of Rover and Rolls-Royce, the Rover jet factory at Barnoldswick was exchanged for the Rolls-Royce Meteor tank engine factory in Nottingham. A handshake sealed the deal. Rover handed over a total of 32 W.2B/23 engines to Rolls-Royce as well as four "straight-through" W.2B/26 engines, developed by Rover's Adrian Lombard. The W.2B/23 became the RB.23 Welland and the W.2B/26 became the RB.26 Derwent. Adrian Lombard moved with the engines from Rover to Rolls-Royce. Stanley Hooker helped in the task of ironing out the remaining problems, and things soon improved. A flight-quality /23 was fitted