Sukhoi Su-35 The initial success of this project led Sukhoi in December 2003 to proceed with a follow-up modernization programme. Known internally as T-10BM, the programme was aimed at a more thorough redesign of the airframe to narrow the qualitative gap between Russian aircraft and foreign so-called fourth-generation aircraft. The resultant design, also designated Su-35, would serve as an interim solution pending the introduction of the Sukhoi Su-57 fifth-generation fighter, many features of which the aircraft would incorporate. Additionally, the aircraft was to be a single-seat alternative to the two-seat design of the Su-30MK on the export market. In many respects, the
Sukhoi Su-15 the Su-15 was abruptly retired from the new Russian Air Force in 1993 to comply with the Treaty on Conventional Armed Forces in Europe. Most were hastily scrapped in favour of more advanced interceptors, including the Su-27 and MiG-31, but some are in reserve storage for emergency use. In Ukraine, the last Su-15s (at Kramatorsk and Belbek) were withdrawn from use in 1996. Some Western reports indicate that the Su-15TM was also designated Su-21 and the Su-15UM Su-21U. These reports are apparently incorrect. Designation Su-21 was reserved for Su-17M4 but never used. Sukhoi Su-15 The Sukhoi Su-15 (NATO reporting name: