The G series, or "Gustav", was introduced in mid-1942. Its initial variants (G-1 through G-4) differed only in minor details from the Bf 109F, most notably in the more powerful 1475 ps (1,455 HP) DB 605 engine. Odd numbered variants were built as high-altitude fighters with a pressurized cockpit and GM-1 boost, while even numbered variants were non-pressurized, air superiority fighters and fighter-bombers. Long-range photo-reconnaisance variants also existed. The later G series (G-5 through G-14) was produced in a multitude of variants, with uprated armament and provision for a number of kits of pre-packaged, generally factory- installed parts known as Umrüst-Bausätze (usually contracted to Umbau) and adding a "/U" suffix to the aircraft designation when installed. Field kits known as Rüstsätze were also available for the G-series but those did not change the aircraft designation.) By early 1944 tactical requirements resulted in the addition of MW-50 water injection boost and high-performance superchargers, boosting engine output to 1,800–2,000 PS (1,775-1,973 HP). From early 1944 a number of G-2s, G-3s, G-4s and G-6s were converted to two seat trainers, known as the G-12. An instructor's cockpit was added behind the original cockpit and both were covered by an elongated, glazed canopy. The so-called Rüstsätze field modification kits and Umrüst-Bausätze factory conversion kits were part of a system promulgated by the RLM as a whole, throughout the German military aviation industry, with each airframe type number having its own set of "/R" and/or "/U" numbered designations for such upgrade packages.
Twee uitvoeringen mogelijk;
- Duitse luchtmacht II.Gruppe/JG 7, eind 1944, Noord Duitsland.
- Duitse luchtmacht IV.Gruppe/JG 27, Begin 1945, Berlijn.
