As I say before, this fanfiction also is an Alternate History.

Kousei's best friend, Tsubaki Sawabe and Watari Ryouta were also conscripted. Like Kousei and Emi they choose the JASDF.  Both are assigned into the strike variant of the F-15, the F-15E Strike Eagle, which has a two-seater cockpit (pilot in the front, combat systems officer in the back).

Specifically, the variant operated by Japan is designated as the F-15EJ. The JASDF acquired two squadron worth of Strike Eagles in summer 2009 to complement it's fleet of F-2s (a joint Japanese-American development of the F-16 Fighting Falcon) and as interim replacement for it's fleet of F-4 Phantom II fighter-interceptors and Mitsubishi F-1 fighter-bombers, with an agreement for the airframes to be assembled by Mitsubishi. 

One of the squadron operated the Strike Eagle is the Dai-Ni-Hikotai, Dai-Ichi-Koukudan (2nd Tactical Fighter Squadron, 1st Air Wing), recently activated with the planes transferred from the 306th Tactical Fighter Squadron, which exchanged it's Eagles for the F-35A Lightning II stealth multirole fighters (in this timeline, the F-35 has been declared fully operational in 2012 and the Japanese soon received theirs in 2014)

This is the illustration of "what-if" Japan has F-15Es. (source: https://schwann90.deviantart.com/art/F-15EJ-JASDF-507264212)

A/N: To @RDCASTILLO22, thanks a lot for your help in advertising this fanfiction teaser and introduction, soon to be a story.