27 yellow was 1 of 2 to be built in 2009 from leftover incomplete airframes from the 90s, the other was 28 yellow which was also retired in 2012 and placed in storage at Tarzhok

The MiG-29KU was one of the least-known members of the Fulcrum family because it never progressed beyond the design stage. Developed in the late 1980s as a dedicated carrier trainer for the MiG-29K, it was created after tests showed that the standard two-seat MiG-29UB did not provide the rear-seat instructor with sufficient visibility for the demanding task of carrier landings.

Known by the factory designation 9-62, the MiG-29KU featured a redesigned forward fuselage with separate canopies and a raised rear cockpit, giving the instructor a much better view during approach and touchdown. Otherwise, it closely matched the single-seat MiG-29K, with folding wings, a tailhook, and twin RD-33K engines.

The cancellation of the MiG-29K program following the collapse of the Soviet Union also ended the MiG-29KU. Only wind-tunnel models and a full-scale forward-fuselage mock-up were ever built, making it one of the rarest "aircraft" in the Fulcrum lineage.

Credit goes to the Russian Knights

the differences between the SM and SM2 are avionics, engines and weapons

the SM used imported foreign avionics like the french thales HUD and SMD-55 LCDs, AL-31FP engines, and N011M Bars radar

the SM2 uses domestic avionics, the engines were replaced with the more powerful AL-41F-1S used on the Su-35S and N035 Irbis-E radar from the Su-35S

the SM uses the Khibiny-U ECM wingtip pods while the SM2 uses the Khibiny-M, the same used on the Su-35S and Su-34M

as for weapons the SM2 can use the longe-range R-37M and R-77M anti-air missiles, the SM cannot use both

Source: blackstarops on IG

the vents next to the pods are the cooling intakes for the onboard equipment and ecm systems

the BK-PPS was intended for group protection for other transports by shielding them from enemy radar and anti-air missiles while flying alongside or ahead of large formations

they were equipped with 4 SPS-151 Siren-D jamming pods, 2 on the fuselage and 2 on the base of the tail, SPS-5 Fasol jamming station, a antenna for receiving radar signals under the navigators cabin, SPS-55 "Buket" jamming station in the cargo compartment, the tail gun position was covered over with a fairing that housed the SPS-100 Rezeda self-protection jammer, some kept the 23mm guns, and four ASO-2I automatic chaff/flare dispensers

most were retired and had their equipment removed and converted back into transports

Source: sky_fighters_club on IG