Yak-120M, Yak-120MF interceptor prototype by A.S.Yakovlev

54k b/w Yak-120M with RD-9F from Yak-25 page at 'Russkaja Sila'

After positive conclusion of Yak-120 in September 1953 Governmental order N°2359-965 was issued, ordering developing the aircraft for new afterburning engine AM-9A and heavy unguided rockets ARS-57. New 'Sokol-M' radar had to be installed. Delays with 'Sokol-M' resulted in delays in aircraft preparation (it was a slightly modified unfinished second Yak-120). Finally it rolled out few months later (December 1954) with series 'Sokol' radar.

It differed from the predecessor by longer (and thicker) engine gondolas, enlarged and shifted outer wing fence, anti-flatter ballasts near pilot tube. Under-fuselage featured two niches for ARS-57 or TRS-190 unguided rockets, what resulted in rearrangement of internal fuel tanks. Some weight was saved by replacing 37mm cannons by 23mm ones (with same ammo amount).

Flight tests of Yak-120M ended in January 1955. 'Sokol-M' radar was not ready (and soon abandoned). AM-9A afterburner could not be used below 5000m, what resulted in somewhat shortfall of the flight characteristics, especially in climb rate. In addition, designers already were preparing for trials new supersonic aircraft (Yak-27). Yak-120M did not went into production, but used for RD-9F trials under Yak-120MF designation.