Su-35 Flanker-E

The Sukhoi Su-35 (NATO reporting name Flanker-E/M) is a single-seat, twin-engine, supermaneuverable 4.5-generation multirole fighter designed by the Sukhoi Design Bureau and built at Komsomolsk-on-Amur (KnAAPO, renamed KnAAZ in 2013). It is the second Su-27 derivative to carry the name, after the canard-equipped Su-27M of the 1980s, which never reached mass production. The modernised Su-35 first flew on 19 February 2008 and entered Russian Aerospace Forces service in February 2014. It is known for its thrust-vectoring Saturn AL-41F1S engines, post-stall manoeuvring and N035 Irbis-E radar, and saw combat over Syria from 2016 and over Ukraine from 2022.

Development

The Soviet Council of Ministers instructed Sukhoi in December 1983 to develop the Su-27M (factory code T-10M) from the Su-27. Canards eliminated buffeting at high angles of attack and let the airframe sustain 10 g against the Su-27's 9 g. The N011 Bars phased-array radar tracked fifteen targets and engaged six, against ten and one for the Su-27's N001, and its weight forward of the cockpit was the original reason for the canards. The first prototype, converted from a T-10S, flew on 28 June 1988 and the first new-build aircraft in April 1992, but the 1990s economic collapse cancelled the planned 1996–2005 production run after two prototypes, nine pre-production and three production aircraft. The eleventh airframe received thrust-vectoring nozzles in 1995 and flew as the Su-37 demonstrator on 2 April 1996; a single two-seat Su-35UB flew on 7 August 2000.

After the Su-27SM upgrade flew in December 2002, Sukhoi launched the T-10BM programme in December 2003 as an export-oriented interim design pending the PAK FA (later Su-57). The canards and dorsal air brake were removed, their contribution to manoeuvrability replaced by thrust vectoring; the fins, dorsal hump and tail boom were shrunk, and wider use of aluminium and titanium alloys and composites cut empty weight. The prototype flew from Zhukovsky on 19 February 2008. The Russian Defence Ministry placed the launch order for 48 Su-35S at MAKS 2009, the first production aircraft flew in May 2011 and state trials began at Akhtubinsk in August 2011. Orders for 50 more followed by the end of 2015, 30 in August 2020, about 24 in 2021 and a fifth batch after the 2022 invasion of Ukraine; the 100th serial aircraft was completed in December 2018.

Design

The Su-35S is 21.9 m (71 ft 10 in) long with a 15.3 m (50 ft 2 in) span, weighs 19,000 kg (41,900 lb) empty and 34,500 kg (76,100 lb) at maximum take-off, and carries 11,500 kg (25,400 lb) of internal fuel. Two Saturn AL-41F1S turbofans (izdeliye 117S), derived from the AL-31F, are each rated at 86.3 kN (19,400 lbf) dry, 137.3 kN (30,900 lbf) in afterburner and 142.2 kN (32,000 lbf) in emergency power. Their nozzles vector in one plane on canted axes, so differential deflection produces roll and yaw as well as pitch; with integrated flight and propulsion controls this allows 9 g manoeuvres and post-stall manoeuvring at low speed, and the engines give a limited supercruise ability above Mach 1.1. Maximum speed is 2,400 km/h (1,490 mph; Mach 2.25) at altitude, range 3,600 km (2,200 mi) or 4,500 km (2,800 mi) with two drop tanks, and service ceiling 18,000 m (59,000 ft).

The Sh135 weapons control complex integrates the N035 Irbis-E passive electronically scanned array, a development of the N011M, which detects aerial targets at up to 400 km (250 mi), tracks thirty and engages eight simultaneously, and maps the ground in synthetic-aperture mode. An OLS-35 electro-optical turret provides infrared search and track, and the L175M Khibiny-M suite supplies electronic countermeasures.

Armament

Internal armament is a 30 mm Gryazev-Shipunov GSh-30-1 cannon with 150 rounds. Twelve stations — two wingtip rails and ten wing and fuselage pylons — carry up to 8,000 kg (17,600 lb). Air-to-air loads include eight R-27ER/ET, six R-73 or R-74, twelve R-77-1 and two R-37 missiles, the aircraft being cleared for air-to-air missiles with ranges of up to 300 km (190 mi). Air-to-surface options are the Kh-29, Kh-31A/AD anti-ship missiles, Kh-31P/PD and Kh-58UShE anti-radiation missiles, Kh-59MK, 3M-14AE and 3M-54AE1 cruise missiles and a single P-800 Oniks, with eight KAB-500 or three KAB-1500 guided bombs and S-13 and S-25 rockets.

Operational History

Twelve Su-35S delivered in February 2014, ten of them to the 23rd Fighter Aviation Regiment at Dzyomgi in Khabarovsk Krai, marked the official entry into service; regiments at Besovets near the Finnish border, Centralnaya Uglovaya near Vladivostok and Khotilovo followed, and the type reached full operational capability in late 2018. The Russian inventory stood at 110 aircraft in December 2022, with deliveries continuing into August 2026.

Russia sent four Su-35S to Khmeimim Air Base, Syria, in January 2016, two months after a Turkish F-16 shot down a Russian Su-24. Over Ukraine, Su-35S flew air superiority missions alongside the Su-30SM and MiG-31; by September 2022 these fighters had at least seven confirmed air-to-air victories over Ukrainian fighters and one over a Ukrainian Naval Aviation Mi-14. Losses include an aircraft shot down near Izyum on 3 April 2022 with its pilot captured, two reportedly downed by Ukrainian MIM-104 Patriot missiles over Bryansk Oblast in May 2023 and one destroyed by a Russian S-300 near Tokmak on 28 September 2023. On 8 July 2026 Ukraine's Air Force said it had shot down a Su-35 near Mostky in Luhansk Oblast, about 42 km (26 mi) from the front line, reportedly with a Patriot, and on 7 September 2026 two Su-35S collided over Kursk Oblast, killing one pilot.

China signed a US$2 billion contract for 24 aircraft in November 2015, without technology transfer; four arrived in December 2016, ten in 2017 and ten in 2018, and the PLAAF commissioned the type in April 2018 with the 6th Aviation Brigade at Suixi, Guangdong. Algeria took delivery in 2025 of airframes built for an Egyptian order abandoned under threat of US CAATSA sanctions: an An-124 was observed loading Su-35s at Komsomolsk-on-Amur on 2 March 2025 and landing at Oum el Bouaghi, and at least four have been seen in Algerian roundels. Iran's deputy defence minister declared the long-reported purchase finalised on 28 November 2023, and an Iranian lawmaker said on 23 September 2025 that the aircraft were "on the way".

Variants

• Su-27M / Su-35 (T-10M): Canard-equipped derivative of the Su-27 with the N011 Bars radar and AL-31FM engines; fourteen flying airframes built by 1995.
• Su-37: Technology demonstrator converted from the eleventh Su-27M in 1995, with thrust-vectoring AL-31FP engines, digital fly-by-wire controls and the N011M radar.
• Su-35UB: Single two-seat trainer flown in August 2000, pairing the Su-27M's canards with a Su-30MKK forward fuselage and thrust-vectoring AL-31FP engines.
• Su-35BM (T-10BM): Unofficial designation for the 2003 redesign marketed by Sukhoi simply as "Su-35", without canards and with the Irbis-E radar and AL-41F1S engines.
• Su-35S: Production version for the Russian Aerospace Forces, "S" standing for Stroyevoy ("combatant"); NATO Flanker-M; in service since February 2014 and exported to China and Algeria.
• Su-35SM: Planned Russian upgrade intended to replace the Irbis-E with the Su-57's N036 Byelka active electronically scanned array and add the Himalaya electronic warfare suite.