In 1947, two MiG-9s were taken by OKB Mikoyan and fitted with the new experimental RD-20F engine, which included a forced-reheat mode for its low-bypass compressors. Essentially a very early form of afterburner/WEP, this new engine was supposed to increase the thrust of the MiG-9, but proved unreliable instead. The two aircraft with this engine received the special prototype designation "I-307". These prototypes are represented in-game as the "MiG-9 Late".

The MiG-9 (l) has been in the game since the start of the Open Beta Test prior to Update 1.27. The MiG-9 Late has two major differences over its predecessor, the first being the underwing fuel tank pods increasing fuel capacity, and the other important change, is the replacement of the RD-20A engines with RD-20F low-bypass engines with not only more power, but also a WEP mode. This rectifies one of the main issues of the older MiG-9, the sluggish acceleration. The new engines and their upgraded acceleration open many new doors for players of the MiG-9. Pilots must still exercise the same playstyle of Boom and Zoom as its predecessor, although the MiG-9 Late's upgraded engines and higher mass allows it to perform this job a lot better. One must be wary of second generation fighter jets especially when uptiered, as those will often decimate the MiG-9 Late in engagements effortlessly.