The Su-27K2, also referred to as the Su-30K2, was part of an IA-PVO program to acquire a long-range air-superiority interceptor intended to replace the Su-27S and Su-27UB fighters. Around 1994, an article claimed that the Ministry of Defense had selected the Su-30K2 prototype as the winner, though this was likely outdated news, since the project was eventually canceled. At the same time, the Ministry also ordered and then canceled acquisitions of other aircraft such as the MiG-29M, MiG-31M, Su-35S, Su-34, and several modernization programs (SMT, BM, SMK).
No photographs of the Su-30K2 were ever published; only speculation suggested it was a two-seat design, either tandem or side-by-side, with indications leaning toward the side-by-side layout. From a technical perspective, the Su-34—with its lower empty weight, more powerful engines, and thrust vector control—could theoretically serve as a multirole air-superiority fighter. Its frontal profile and integrated Su-27 design would make it formidable, though its heavy weight limited maneuverability, climb rate, and load factor in such a role.
The Su-30K2 may have been used in the development of the Su-33UB, or vice versa. [...]