Messerschmitt Bf 109 was called the Me 109R, suggesting it was just another variant of the standard fighter, but in fact it was a racing aircraft having little in common with the Bf 109. It was powered by the DB 601ARJ, producing 1,156 kW (1,550 hp), but capable of reaching 1,715 kW (2,300 hp). This world record for a piston-engined aircraft was to stand until 1969, when Darryl Greenamyer's modified Grumman F8F Bearcat, "Conquest I", broke it with a 777 km/h (483 mph) record speed. When the Bf 109 was designed in 1934, by a team led by Willy Messerschmitt and Robert Lusser,
Operational history of the Luftwaffe (1939–45) fighter losses increased. The introduction of the B-17G with its remote controlled 'chin' turret forced a change of tactic on the "Jagdwaffe". Throughout 1943 head-on attacks had proved successful against American heavy bombers. Many Luftwaffe units now upgraded the firepower of their fighters. Some Fw 190 fighters carried MK 108 30 mm cannon that could destroy most heavy bombers with two or three hits. The later variants of the Messerschmitt Bf 109 (from the" Gustav" onwards) were also capable of carrying heavier armament like the MK 108, although only a single barrel firing through the propeller shaft as an engine-mounted