This strange-shaped plane was altered as a ECM trainer based on the tactical transporter C-1 in 1986.
The plane is nicknamed "DUCKBILL" has been wrapped in the veil of mystery. There are no logo of "KOKU-JIEITAI"(JASDF), and no squadron mark.
Moreover, it is a mysterious airframe to which a loaded electronic system and internal details are not clarified.
Though this is a training plane, this plane is really a fully functional ECM airplane. The purpose of this plane is to jam an enemy's radar site etc. and disturbing it from far away. This airplane is a "stand off jammer".
Two antenna for the low-frequency band mounted on diagonally were installed in fore and aft radome.
Moreover, the antenna for the high frequency band was installed in the radome mounted on port and starboard, and it became possible to put out the jamming wave by these antennas over all directions.
