The Rolls-Royce Merlin liquid-cooled V-12 piston aero engine is considered an icon of British engineering with a worldwide recognition. It was one of the most successful aircraft engines of the Second World War period and its incremental development ran hand in hand with that of the legendary Supermarine Spitfire to which it was fitted from the very beginning. From its genesis in the 740hp PV-12 engine that was first flown in 1935, the Merlin went...