Sukhoi Su-35 Fighter Jet - Russia:
The Sukhoi Su-35 is a designation for two separate, heavily upgraded derivatives of the Su-27 aircraft. They are single-seat, twin-engine, supermaneuverable multirole fighters, designed by Sukhoi and built by Komsomolsk-on-Amur Aircraft Production Association (KnAAPO).
The first variant of the Sukhoi Su-35 was designed during the 1980s, when Sukhoi sought to upgrade its high-performance Su-27, and was initially known as the Su-27M. Later re-designated Su-35, this derivative incorporated aerodynamic refinements with increased manoeuvrability, enhanced avionics, longer range, and more powerful engines. The first Su-35 prototype, converted from a Su-27, made its maiden flight in June 1988. More than a dozen of these were built, some of which were used by the Russian Knights aerobatic demonstration team. The first Su-35 design was later modified into the Su-37, which possessed thrust vectoring engines and was used as a technology demonstrator. A sole Su-35UB two-seat trainer was built in the late 1990s that strongly resembled the Su-30MK family.
In 2003, Sukhoi embarked on a second modernization of the Su-27 to produce what the company calls a 4++ generation fighter that would bridge the gap between legacy fighters and the upcoming fifth-generation Sukhoi PAK FA. This derivative, while omitting the canards and air brake, incorporates a reinforced airframe, improved avionics and radar, thrust-vectoring engines, and a reduced frontal radar signature. In 2008 the revamped variant, erroneously named the Su-35BM in the media, began its flight test programme that would involve four prototypes, one of which was lost in 2009.
The Russian Air Force has ordered 98 production units, designated Su-35S, of the newly revamped Su-35. Both Su-35 models were marketed to many countries, including Brazil, China, India, Indonesia, and South Korea; only China has so far ordered the Su-35, placing an order for 24 in late 2015. Indonesia expressed an intent to buy between 8-10 Su-35s in 2015, but has yet to sign a final purchase contract. Other countries have since either purchased other aircraft or lost interest in the Su-35. Sukhoi originally projected that it would export more than 160 units of the second modernized Su-35 worldwide, but sales of the Su-35 have been blunted by updated versions of the Sukhoi Su-30, and by the development of stealthy fifth generation aircraft, including Sukhoi's own T-50/Sukhoi PAK FA. More details