In 2003, Sukhoi embarked on a second modernization of the Su-27 to produce what the company calls a 4++ generation fighter that would serve as an interim fighter prior to the arrival of the Sukhoi PAK FA. This derivative incorporates a reinforced airframe, improved avionics and radar, thrust-vectoring engines, and a reduced radar signature from the front, while omitting the canards and air brake. In 2008 the revamped variant, erroneously dubbed the Su-35BM by the media, started its flight test programme that involved four prototypes, one of which was lost in 2009.
The Russian Air Force has ordered 48 production units, designated Su-35S, of the newly-revamped Su-35. Both Su-35 models have been offered to many countries, including Brazil, China, India and South Korea, but so far have not attracted any export orders. Sukhoi originally projected that it would export more than 160 units of the second modernized Su-35 worldwide.