The Messerschmitt Bf.109 was a single-seat monoplane fighter used by the Luftwaffe before and during WWII. It was used as a fighter, interceptor, high-altitude interceptor, fighter-bomber and reconnaissance aircraft.
The Bf.109G-6 "Gustav" was the most mass-produced variant of the Gustav series. It entered production in the late Autumn of 1942, and was initially designed as a universal platform which could be quickly converted to various roles as needed in field conditions. The G-6 was also equipped with improved engines, either with MW 50 methanol-water injection, or the high-altitude GM-1 nitrous oxide injection. The DB605AS engine, which used 96-octane fuel, as opposed to 87-octane, could reach over 2,000 HP at 500 m and 1,800 HP at 5,000 m. These variants were designated Bf.109G-6/AS. The armoured seat had a transparent seat back, which significantly improved visibility. A total of 700 /AS aircraft were produced.
In addition to those changes, the G-6 was also the first to house the 30mm MK 108 cannon, which had 60 specially designed incendiary shells. A single hit was usually enough to destroy a single-seat fighter, most bombers needing no more than 4 or 5 hits.