The Sukhoi Su-35 (Russian: Сухой Су-35; NATO reporting name: Flanker-E/M, occasionally nicknamed "Super Flanker"[6]) is the designation for two improved derivatives of the Su-27 air-defence fighter.

Also known as the Su-35, this version incorporates technology from the PAK FA program and has a redesigned cockpit and weapons-control system and features thrust-vectoring engines in place of the canards.

[citation needed] While sharing broadly the blended wing-body design of the Su-27, the Su-27M is visibly distinguished from the basic version by the addition of canards, which are small lifting surfaces, ahead of the wings.

First tested in 1985 using an experimental aircraft,[8] the canards, in complement with the reshaped wing leading-edge extension, redirected the airflow in such a way so as to eliminate buffeting at high angles of attack and allowed the airframe to sustain 10-g manoeuvres (as opposed to 9 g on the Su-27) without additional structural reinforcement.

[12] More importantly, when working with the relaxed-stability design and the accompanying fly-by-wire flight-control system, the aerodynamic layout improved the aircraft's manoeuvrability and enabled it to briefly fly with its nose past the vertical while maintaining forward momentum.

[13] Other notable visible changes compared to the T-10S design included taller vertical tails, provisions for in-flight refuelling and the use of two-wheel nose undercarriage to support the heavier airframe.

[23] The aircraft subsequently made flying demonstrations overseas in an effort to attract export orders, starting in November 1993 with Dubai, where Viktor Pugachev flew it in a mock aerial engagement with an Su-30MK in front of spectators.

[31] While the original Su-27M never entered mass production due to a lack of funding,[32] Sukhoi refined the Su-27M's use of canards and the Su-37's thrust-vectoring technology and later applied them to the Su-30MKI two-seat fighter for the Indian Air Force.

[1][36][37] Initially, the aircraft was primarily aimed at the export market, being offered by KnAAPO as a single-seat alternative to the two-seat Su-30MK variants built by Irkutsk Aviation Plant (IAP).

[59] The flight-test programme was expected to involve three flying prototypes, but on 26 April 2009, a day before its scheduled maiden flight, the fourth Su-35 (there's a static test aircraft) crashed during a taxi run at Dzyomgi Airport.

[6][65][38] During the early stages of the flight-test programme, Sukhoi estimated that there was such a market for 160 aircraft, with a particular emphasis on Latin America, Southeast Asia and the Middle East.

[68] Apart from the launch order at the 2009 MAKS Air Show, the Russian government and the state-owned Vnesheconombank development bank agreed to provide Sukhoi with capital for the aircraft's production.

[citation needed] In May 2011, Sukhoi delivered the first Su-35S to Akhtubinsk to conduct state joint tests with the Defence Ministry to prepare for operational service.

By March 2012, the two prototypes and four production aircraft were conducting flights to test the type's technical characteristics,[76] which were assessed by the end of that year to have generally complied with requirements.

[102][103] On 9 May, the Ukraine Defence Ministry confirmed that Colonel Ihor Bedzay, the deputy head of the Ukrainian Navy Aviation Office, was killed in action.

[113] According to the International Institute for Strategic Studies, Russia has lost more than five Su-35 fighters since the beginning of the Ukraine war, either to friendly fire, crashed[114] or Ukrainian forces shooting down[115] the aircraft using Western-supplied air defences.

[119] In November 2015, China became the Su-35's first export customer when the Russian and Chinese governments signed a contract worth $2 billion to buy 24 aircraft for the People's Liberation Army Air Force.

[122] However, the low number of purchases also signified that the deal was symbolic in nature, as the two countries are still competing over influence in Central Asia, according to Moritz Rudolf of Mercator Institute for China Studies.

"[122] Chinese officials had reportedly first shown interest in the Su-35 in 2006,[123] it was not until Zhuhai Airshow 2010 that Alexander Mikheyev of the Rosoboronexport, the Russian state agency responsible for the export and import of defence products, signified that Russia was ready to start talks with China over the Su-35.

The Kremlin again intervened and conceded to this demand, allowed the deal to proceed; it was viewed as a major concession since the sales of such components are reportedly lucrative.

[133][134] Followed by the first delivery, the People's Liberation Army's website opined that with the J-20's commissioning, Russia understood that the Su-35 would "lose its value on the Chinese market in the near future...we hope very much that Su-35 will be the last (combat) aircraft China imports.

[143] However, in July 2023, the Iranian Defense Minister, Mohammad-Reza Gharaei Ashtiani, made vague statements alluding that Iran is reconsidering the acquisition of the Su-35 due to increasing investment towards indigenous fighter building capabilities, leading to some sources to declare that the deal has collapsed.

[144] Despite this, the Iranian Air Force has received deliveries of the Yak-130 advanced jet trainer, which are used to train aspiring cadets before they graduate to actual fighter aircraft, such as the Su-35.

[151] According to Kommersant, the Algerian military had requested a Su-35 for testing in February 2016; it was reported the country was satisfied with the fighter's flight characteristics and so Moscow is waiting for a formal application.

[citation needed] Sudan has reportedly also expressed an interest in acquiring of the Su-35 fighters during the Sudanese president Omar Hassan al-Bashir's visitation of Moscow in November 2017.

[citation needed] Although the Brazilian government eliminated the Su-35 in 2008,[166] Rosoboronexport subsequently offered to sell the country 120 aircraft with full technology transfer,[167] as well as participation in the PAK FA programme.

[181] In 2015, the Su-35 was selected based on the Indonesian Air Force's familiarity with the Su-27SK and Su-30MK2; the other competitors were the Eurofighter Typhoon, Dassault Rafale, F-16 and Saab JAS 39 Gripen.

[191] Sukhoi proposed a design which featured a phased-grid radar and thrust-vectoring engines, and offered full technology transfer as well as final assembly in South Korea.

[60] On 31 July 2021, a Su-35S fighter crashed after suffering an engine failure during a routine training mission in the Khabarovsk Territory in Russia, according to statement from the Russian Defence Ministry.

[228] According to a preliminary investigation reported by the Russian newspaper Top War, the Su-35 suffered technical malfunctions in the environment control systems that indicate heating and cooling functions.