|A Su-57 with serial production pixel camouflage|
|Manufacturer||Komsomolsk-on-Amur Aircraft Plant|
|First flight||29 January 2010|
|Introduction||25 December 2020[N 1]|
|Primary user||Russian Aerospace Forces|
|Number built||16 (10 test and 6 serial)|
The Sukhoi Su-57 (Russian: Сухой Су-57; NATO reporting name: Felon) is a twin-engine stealth multirole fighter aircraft developed by Sukhoi. It is the product of the PAK FA (Russian: ПАК ФА, short for: Перспективный авиационный комплекс фронтовой авиации, romanized: Perspektivnyy Aviatsionnyy Kompleks Frontovoy Aviatsii, lit. ''prospective aeronautical complex of front-line air forces'') programme, which was initiated in 1999 as a more modern and affordable alternative to the MFI (Mikoyan Project 1.44/1.42). Sukhoi's internal designation for the aircraft is T-50. The Su-57 is the first aircraft in Russian military service designed with stealth technology and is intended to be the basis for a family of stealth combat aircraft.
A multirole fighter capable of aerial combat as well as ground and maritime strike, the Su-57 incorporates stealth, supermaneuverability, supercruise, integrated avionics, and substantial internal payload capacity. The aircraft is expected to succeed the MiG-29 and Su-27 in the Russian military service and has also been marketed for export. The first prototype aircraft flew in 2010, and after a protracted development due to various issues that emerged during trials, including the destruction of the first production aircraft in a crash before its delivery, the first Su-57 entered service with the Russian Aerospace Forces (VKS)[N 2] in December 2020. The fighter is expected to have a service life of up to 35 years.
In 1979, the Soviet Union outlined a need for next-generation fighter aircraft intended to enter service in the 1990s. The programme became the I-90 (Russian: И-90, short for: Истребитель 1990–х годов, lit. 'Fighter of the 1990s') and required the fighter to be "multifunctional" (i.e., multirole) by having substantial ground attack capabilities, and would eventually replace the MiG-29 and Su-27 in frontline tactical aviation service. Two subsequent projects were designed to meet these requirements: the MFI (Russian: МФИ, short for: Многофункциональный фронтовой истребитель, lit. 'Multifunctional Frontline Fighter') and smaller LFI (Russian: ЛФИ, Л short for: Лёгкий, lit. 'Light'), with conceptual work beginning in 1983.[N 3] Mikoyan was selected for the MFI and began developing its MiG 1.44/1.42. Though not a participant in the MFI, Sukhoi started its own programme in 1983 to develop technologies for a next-generation fighter, eventually resulting in the forward-swept wing S-32 experimental aircraft, later redesignated S-37 and then Su-47. Due to a lack of funds after the dissolution of the Soviet Union, the MFI was repeatedly delayed and the first flight of the MiG 1.44/1.42 prototype did not occur until 2000, nine years behind schedule. Owing to the high costs, the MFI and LFI were eventually cancelled and the Russian Ministry of Defence began work on a new next-generation fighter programme; in 1999, the ministry initiated the PAK FA or I-21 programme, with the competition announced in April 2001.[N 4] Because of Russia's financial difficulties, the programme aimed to rein in costs by producing a single multirole fifth-generation fighter that would replace both the Su-27 and the MiG-29. Further cost-saving measures include an intended size in between that of the Su-27 and the MiG-29 and normal takeoff weight considerably smaller than the MiG MFI's 28.6 tonnes (63,000 lb) and the Su-47's 26.8 tonnes (59,000 lb).
Sukhoi's approach to the PAK FA competition differed fundamentally from Mikoyan's; whereas Mikoyan proposed for the three design bureaus (Mikoyan, Sukhoi, and Yakovlev) to cooperate as a consortium with the winning team leading the design effort, Sukhoi's proposal had itself as the lead designer from the beginning and included a joint work agreement that covered the entire development and production cycle, from propulsion and avionics suppliers to research facilities. Additionally, the two companies had differing design philosophies for the aircraft. Mikoyan's E-721 was smaller and more affordable, with normal takeoff weight of 16–17 tonnes (35,000–37,000 lb) and powered by a pair of Klimov VK-10M engines with 10–11 tonnes (98.1–108 kN, 22,000–24,300 lbf) of thrust each. In contrast, Sukhoi's T-50 would be comparatively larger and more capable, with normal takeoff weight goal of 22–23 tonnes (49,000–51,000 lb) and powered by a pair of Lyulka-Saturn AL-41F1 engines each with maximum thrust in the 14.5-tonne (142 kN, 32,000 lbf) class.[N 5]
In April 2002, the Ministry of Defence selected Sukhoi over Mikoyan as the winner of the PAK FA competition and the lead design bureau of the new aircraft.[N 6] In addition to the merits of the proposal, Sukhoi's experience in the 1990s was taken into account, with the successful development of various Su-27 derivatives and numerous exports ensuring its financial stability. According to the Russian Air Force Commander-in-Chief Vladimir Mikhaylov, flight tests were projected to begin in 2007. Mikoyan continued to develop its E-721 as the LMFS (Russian: ЛМФС, short for: Лёгкий многофункциональный фронтовой самолёт, lit. 'Light Multifunctional Frontline Aircraft') at its own expense.
Research and development
The research and development programme of the PAK FA was called Stolitsa (Russian: Столица, lit. 'Capital city'). In 2002, Alexander Davidenko selected as the T-50's chief designer at Sukhoi. The Novosibirsk Aircraft Production Association (NAPO) and Komsomolsk-on-Amur Aircraft Production Association (KnAAZ) would manufacture the new multi-role fighter, with KnAAZ performing final assembly at Komsomol'sk-on-Amur. Following a competition held in 2003, the Tekhnokompleks Scientific and Production Center, Ramenskoye Instrument Building Design Bureau, the Tikhomirov Scientific Research Institute of Instrument Design (NIIP), the Ural Optical and Mechanical Plant (UOMZ) in Yekaterinburg, the Polet firm in Nizhny Novgorod and the Central Scientific Research Radio Engineering Institute in Moscow were selected for the development of the PAK FA's avionics suite. In April 2004, NPO Lyulka-Saturn (now NPO Saturn) was signed as the contractor for the AL-41F1 engines with the development designation izdeliye 117.[N 7]
Sukhoi used existing airframes as testbeds for various subsystems and concepts; the Su-47 was used to test internal weapon bays, and Su-27M prototypes tested the flight control system and engines. To reduce developmental risk and spread out associated costs, as well as to bridge the gap with extant fourth generation fighters, Sukhoi implemented some of its technology and features, such as propulsion and certain avionics, in an advanced derivative of the Su-27 called the T-10BM (Russian: БМ, short for: большая модернизация, lit. 'Major Modernization'), which eventually entered Russian service as the Su-35S in 2014.
In December 2004, the T-50's conceptual design and shape was complete and approved by the Ministry of Defence; government funding of the programme began in 2005 and drastically increased in 2006 when detailed design was underway. On 8 August 2007, Russian Air Force Commander-in-Chief Alexander Zelin was quoted by Russian news agencies that the programme's development stage was complete and construction of the first aircraft for flight testing would begin, with three flyable T-50 prototypes planned to be built by 2009. In 2009, the aircraft's design was officially approved. The T-50 was named Su-57 in July 2017.
Since the early stages of the PAK FA programme, Russia sought after foreign partnerships on the project to increase funding for its development and also secure large export orders. On 18 October 2007, Russia and India signed a contract for Sukhoi and Hindustan Aeronautics Limited (HAL) to jointly develop a derivative of the PAK FA called the Fifth Generation Fighter Aircraft (FGFA). In September 2010, India and Russia agreed on a preliminary design contract where each country was to invest $6 billion; a memorandum of understanding for the preliminary design was signed in December 2010, and the development of the FGFA was expected to take 8–10 years. By 2014, however, the Indian Air Force began voicing concerns over performance, cost, and workshare. India eventually left the partnership in 2018.
The T-50's maiden flight was repeatedly postponed from early 2007 after encountering unspecified technical problems. In August 2009, Alexander Zelin acknowledged that problems with the engine and in technical research remained unsolved. On 28 February 2009, Sukhoi general director Mikhail Pogosyan announced that the airframe was almost finished and that the first prototype should be ready by August 2009. On 20 August 2009, Pogosyan said that the first flight would be by year's end. Konstantin Makiyenko, deputy head of the Moscow-based Centre for Analysis of Strategies and Technologies said that "even with delays", the aircraft would likely make its first flight by January or February, adding that it would take five to ten years for commercial production. Flight testing was further delayed when Deputy Prime Minister Sergei Ivanov announced in December 2009 that the first trials would begin in 2010. The first taxi test was successfully completed on 24 December 2009, and the maiden flight of the first prototype aircraft, T-50-1, occurred on 29 January 2010. Piloted by Sukhoi test pilot Sergey Bogdan, the aircraft's 47-minute maiden flight took place at KnAAPO's Dzemgi Airport in the Russian Far East. Construction of the prototypes would progress slower than initially planned; by the end of October 2013, the test programme had amassed more than 450 flights across five aircraft.
A total of ten flying and three non-flying T-50 prototypes would be built for preliminary flight tests and state trials. Initially, the program was planned to have up to six prototypes before the start of serial production; however testing would reveal that the initial prototypes did not have adequate fatigue life, with early structural cracks forming in the airframe. The aircraft subsequently underwent a structural redesign, with changes including increased composite material usage, reinforced airframe to meet full life cycle requirements, elongated tail "sting", and slightly greater wingspan; the sixth flyable prototype was the first of the redesigned "second stage" aircraft, with the five initial prototypes consequently considered "first stage" vehicles and requiring additional structural reinforcements in order to continue flight tests.[N 8] The last two flying prototypes were test articles of production Su-57 aircraft with full mission systems on board. While the "second stage" structural redesign reduced the weight growth from the required strengthening of the "first stage" design, the normal takeoff weight still increased to approximately 25 tonnes (55,000 lb). Issues and accidents during the testing resulted in repeated delays to the programme, with the delivery of the first production aircraft pushed back from 2015 to 2020.
The procurement plans for the PAK FA have been considerably scaled back and delayed from original plans. In 2011, the Ministry of Defence had planned on buying the first 10 aircraft for evaluation after 2012 and 60 production standard aircraft after 2015. These plans were refined under the State Armament Programme from 2011 to 2020 (GPV-2020), with serial production hoped to begin in 2016; the Ministry of Defence was planning to acquire 52 aircraft by 2020, and another 150–160 by 2025. Additionally, export orders for 250–300 FGFA were expected to begin in 2017.
Plans were greatly cut down in 2015 as a result of technical obstacles encountered during testing, India's unclear commitment to the partnership, and Russia's economic downturn due to Western sanctions after its annexation of Crimea and the drop in oil prices. Russian Deputy Minister of Defence Yury Borisov stated in 2015 that the Russian Air Force would slow production, reduce its initial order to 12 fighters, and operate large fleets of upgraded fourth-generation fighters such as the Su-35S and the Su-30SM. In 2017, Borisov stated that the PAK FA would most likely enter service in 2018 and be part of the new State Armament Programme from 2018 to 2027 (GPV-2027). On 30 June 2018, an order for 12 aircraft was agreed, while deliveries to the Russian Armed Forces was pushed back again to 2019 with the first aircraft planned to join fighter regiments at the Lipetsk Air Center. At the same time, Borisov praised the Su-35S, stating that it was comparable to the Su-57 except for the stealth features while being more affordable.
Due to the substantially higher cost of the Su-57 compared to the Su-35S and Su-30SM, the design was placed on hold for mass production until the need arises. On 22 August 2018, during the International Military-Technical Forum «ARMY-2018», the Defence Ministry and Sukhoi signed the first contract for delivery of two serial Su-57 fighters scheduled for 2019 and 2020 respectively. In January 2019, the Ministry of Defence announced they hoped to conclude a second contract for 13 more aircraft in 2020.
However, on 15 May 2019, the acquisition plan drastically changed when Russian President Vladimir Putin announced that 76 aircraft would be purchased and delivered to the Aerospace Forces by 2028. This came after the negotiations were able to lower the price of the Su-57 and equipment by 20%. The contract for the 76 aircraft was formally signed on 27 June 2019 at the International Military-Technical Forum «ARMY-2019». The same month, General Director of Tactical Missiles Corporation (KRTV) Boris Obnosov reported, a contract for serial production of ammunition for Su-57 fighters was signed, and is being inducted. Serial production of the aircraft began in July 2019, with the first production aircraft scheduled to be delivered by the end of the year; following the crash of the first production aircraft, the Russian Aerospace Forces[N 2] took delivery of its first Su-57 in December 2020. By May 2022, four more aircraft were delivered, and production has progressed slower than planned.
In 2004, Sukhoi anticipated that the Su-57 could become the basis for a family of combat aircraft for the Russian Aerospace Forces, similar to the Su-27 family. Under the program name Megalopolis (Russian: Мегаполис, lit. 'Megalopolis'), the company is developing a new variant, designated Su-57M, that augments the base Su-57 design with improved mission systems, reliability and maintenance enhancements, incorporation of electromechanical drives, and the new NPO Saturn izdeliye 30 engines. The formal contract was signed in 2018, although preliminary work had begun earlier. In 2020, flight test of the improved variant was planned to begin in 2022, with serial production in the mid-2020s. The second flying T-50 prototype was used to test the new izdeliye 30 engine starting in 2017; the third prototype was configured for teaming tests with the Okhotnik UCAV in 2018. Additionally, work is underway to make a variant of the aircraft that can operate on aircraft carriers.
Sukhoi has also used technology from the Su-57 to produce a mockup of a more affordable lightweight single-engine aircraft, designated as the LTS (Russian: ЛТС, short for: Лёгкий тактический самолёт, lit. 'Light Tactical Aircraft'). At the 2021 Moscow Air Show (MAKS-2021), Sukhoi revealed its LTS mockup, named Checkmate, which shares many systems with the Su-57, including radar, main weapons bay, vertical stabilizers, and wings.
As of 2022[update], continued Su-57 development could be delayed due to international sanctions on Russia's defence industries, and Russia could not import semiconductors and high-tech machining equipment from the European Union. The potential export sales also stalled because Russia cannot trade using U.S. dollars.
The Su-57 is a fifth-generation multirole fighter aircraft and the first operational stealth aircraft for the Russian armed forces. In addition to stealth, the fighter emphasizes supermaneuverability in all aircraft axes, capacious internal payload bays for multirole versatility, and advanced sensor systems such as active phased-array radar as well as the integration of these systems to achieve high levels of automation. In the Su-57's design, Sukhoi cited the Lockheed Martin F-22 as the baseline for a supermaneuverable stealth fighter, but addressed what the bureau considered to be the limitations, such as the inability to use thrust vectoring to induce roll and yaw moments, a lack of space for weapons bays between the engines resulting in insufficient payload, and complications for stall recovery if thrust vectoring fails.
The aircraft has a wide blended wing body fuselage with two widely spaced engines and has all-moving horizontal and vertical stabilisers, with the vertical stabilisers canted for stealth; the trapezoid wings have leading edge flaps, ailerons, and flaperons. The aircraft incorporates thrust vectoring and large leading edge root extensions that shift the aerodynamic center forward, increasing static instability and maneuverability. These extensions have adjustable leading–edge vortex controllers (LEVCONs) designed to control the generated vortices and can provide trim and improve high angle of attack behaviour, including a quick stall recovery if the thrust vectoring system fails. To air-brake, the ailerons deflect up while the flaperons deflect down and the vertical stabilisers toe inward to increase drag. Although the majority of the structural materials are alloys with 40.5–44.5% aluminum alloys and 18.6% titanium alloys, the aircraft makes extensive use of composites, with the material comprising 22–26% of the structural weight and approximately 70% of the outer surface.
Designed from the outset as a multirole aircraft, the Su-57 has substantial internal payload capacity that allows the carriage of large air-to-surface ordnance. Weapons are housed in two tandem main weapons bays in the large ventral volume between the widely spaced engine nacelles and smaller side bays with bulged triangular-section fairings near the wing root. Internal weapons carriage eliminates drag from external stores and enables higher performance compared to external carriage, as well as preserving the stealth shaping.
The high degree of static instability (or relaxed stability), advanced KSU-50 flight control system, and canted thrust vectoring nozzles make the Su-57 departure-resistant and highly maneuverable in both pitch and yaw, enabling the aircraft to perform very high angles of attack maneuvers such as the Pugachev's Cobra and the bell maneuver, along with doing flat rotations with little altitude loss. The aerodynamics and engines enable it to achieve speeds of Mach 2 and fly supersonic without afterburners (supercruise) giving a significant kinematic advantage and extends the effective range of missiles and bombs over previous generations of aircraft.[N 9] Combined with a high fuel load, the fighter has a supersonic range of over 1,500 km (930 mi), more than twice that of the Su-27. An extendable refueling probe is available to further increase its range.
The first aircraft in Russian military service to emphasize stealth, the Su-57 employs a variety of methods to reduce its radar signature. Similar to other stealth fighters such as the F-22, the aircraft aligns the planform edges to reduce its radar cross-section (RCS); the leading and trailing edges of the wings and control surfaces and the serrated edges of skin panels are carefully angled to reduce the number of directions the radar waves can be reflected. Weapons are carried internally in weapons bays within the airframe and antennas are recessed from the surface of the skin to preserve the aircraft's stealthy shape, while radar absorbent material (RAM) coatings absorb radar emissions and reduce the reflection back to the source. The infrared search-and-track sensor housing is turned backwards when not in use and its rear is also treated with RAM. To mask the significant RCS contribution of the engine face, the walls of the inlet ducts are coated with RAM and the partial serpentine ducts obscure most of the engines’ compressor face and inlet guide-vanes (IGV); the remaining exposed engine face is masked by a slanted blocker grid placed in front of the IGV at a distance of 0.7—1.2 times the diameter of the duct, similar in principle to the method on the Boeing F/A-18E/F. The aircraft canopy is coated with 70–90 nm thick metal oxide layers with enhanced radar wave absorbing to minimize the radar return of the cockpit by 30% and protect the pilot from the impact of ultraviolet and thermal radiation. The production tolerances are significantly tighter than previous Russian fighters in order to improve stealth characteristics.
The combined effect of airframe shape and RAM of the production aircraft is estimated to have reduced the aircraft's RCS to a value thirty times smaller than that of the Su-27. Sukhoi's patent for the T-50 stealth features cites an intention to reduce average RCS to approximately 0.1 to 1 m2, compared to the Su-27's RCS of approximately 10 to 15 m2. The Su-57's design emphasizes frontal stealth, with RCS-reducing features most apparent in the forward hemisphere; the shaping of the aft fuselage is less optimized for radar stealth compared to American stealth designs such as the F-22 and F-35, likely as a result of cost reduction as well as the Russian doctrine of operating the aircraft within the umbrella of friendly integrated air defense systems. As with other stealth fighters, the Su-57's low observability measures are chiefly effective against high-frequency (between 3 and 30 GHz) radars, usually found on other aircraft. The effects of Rayleigh scattering and resonance mean that low-frequency radars, employed by weather radars and early-warning radars are more likely to detect the Su-57 due to its size. Such radars are also large, susceptible to clutter and are less precise.
The Su-57 is powered by a pair of NPO Lyulka-Saturn izdeliye 117, or AL-41F1, augmented turbofans. The engine is a highly improved and uprated variant of the AL-31 and produces 9 tonnes (88.3 kN, 19,840 lbf) of dry thrust, 14.5 tonnes (142.2 kN, 31,970 lbf) of thrust in afterburner, and 15 tonnes (147.1 kN, 33,070 lbf) of thrust in "special" emergency power. The engines have full authority digital engine control (FADEC) and are integrated into the flight control system to facilitate maneuverability and handling. The AL-41F1 is closely related to the Lyulka-Saturn izdeliye 117S engine, or AL-41F1S, used by the Su-35S, with the latter's separate engine control system being the key difference.
The aircraft employs thrust vector control (TVC) where the vectoring nozzles' rotational axes are each canted at an angle, similar to the nozzle arrangement of the Su-35S. The nozzles themselves vector in only one plane; the canting allows roll and yaw moments by vectoring each nozzle differentially, thus enabling the aircraft to produce thrust vectoring moments about all three aircraft axes, pitch, yaw and roll. The engine inlet incorporates variable intake ramps for supersonic efficiency and retractable mesh screens to prevent engine damage from foreign object debris ingestion especially when operating in short, austere runways. In 2014, the Indian Air Force openly expressed concerns over the reliability and performance of the AL-41F1; during the 2011 Moscow Air Show, a Su-57 suffered a compressor stall that forced the aircraft to abort takeoff.
The planned Su-57M will be equipped with a new engine from NPO Saturn in the mid-2020s under the development designation izdeliye 30. The engine is designed with an estimated thrust of 11 tonnes (107.9 kN, 24,300 lbf) dry and 17.5 tonnes (171.7 kN, 38,600 lbf) in afterburner. In addition to improved performance, reliability, and costs compared to the AL-41F1, the new powerplant will also reduce the aircraft's radar and infrared signature with glass-fibre plastic IGVs and a new nozzle with serrated flaps.
The Su-57 has two tandem main internal weapon bays each approximately 4.4 m (14.4 ft) long and 0.9 m (3.0 ft) wide and two side weapon bays with triangular section fairings under the fuselage near the wing root. The main bays have two types of ejection launchers made by Vympel, the UVKU-50L for missiles weighing up to 300 kg (660 lb) and the UVKU-50U for ordnance weighing up to 700 kg (1,500 lb); the side bays use the VPU-50 launch rails.
For air-to-air combat, the Su-57 carries four beyond-visual-range missiles in its two main weapons bays and two short-range missiles in the side bays. The primary medium-range missile is the active radar-homing R-77M (izdeliye 180), an upgraded R-77 variant with AESA seeker, dual-pulse motor, and conventional rear fins. The short-range missile is the infrared-homing ("heat seeking") R-74M2 (izdeliye 760), an upgraded R-74 variant with reduced cross-section for internal carriage. A clean-sheet design short-range missile designated K-MD (izdeliye 300) is being developed to eventually replace the R-74M2. For longer ranged applications, the izdeliye 810 missile, a further development of the R-37M, can be carried with two in each main weapons bay.
For striking surface targets, the aircraft can carry the 250 kg (550 lb) KAB-250 or 500 kg (1,100 lb) KAB-500 precision guided bombs in its main bays. Internal weapons also include the Kh-38M air-to-ground missile, Kh-35U (AS-20 "Kayak") anti-ship missile, Kh-58UShK (AS-11 "Kilter") anti-radiation missile, and Kh-59MK2 cruise missile. For missions that do not require stealth, the Su-57 can carry stores on its six external hardpoints which can use most Russian tactical fighter weapons. New hypersonic missile with characteristics similar to the Kh-47M2 Kinzhal ALBM is also being developed for the Su-57. The missile is to have intra-body accommodation and smaller dimensions to allow it to be carried inside the Su-57's main bays.
The aircraft has a 9A1-4071K (GSh-30-1) 30 mm autocannon with 150 cartridges mounted internally near the right LEVCON root. The weapon has an effective range of 800 m (870 yd) against aerial targets and 1,800 m (2,000 yd) against surface targets.
The Su-57 has a glass cockpit with no analogue gauges; information is displayed on two 38 cm (15 in) main multi-functional LCD displays similar to the arrangement of the Su-35S. Supplementing the primary display is a smaller multi-functional display and digital control panel. The cockpit has a wide-angle (30° by 22°) head-up display (HUD). Primary controls are the joystick and a pair of throttles, with all major functions controlled with hands on throttle and stick (HOTAS). The aircraft uses a two-piece canopy, with the aft section sliding forward and locking into place. The canopy is treated with metallized coatings to reduce the aircraft's radar signature.
The aircraft uses the NPP Zvezda K-36D-5 ejection seat and the SOZhE-50 life support system, which comprises the anti-g and oxygen generating system. The pilot is equipped with ZSh-10B helmet which mounts the NSTsI-50 digital display system, which enhances pilot situational awareness through pupil tracking and allows engagement of targets at high angles off-boresight. The 30 kg (66 lb) oxygen generating system provides the pilot with unlimited oxygen supply. The life support system enables pilots to perform 9-g maneuvers for up to 30 seconds at a time, while the ejection seat and the new PPK-7 flight suit allows safe ejection at altitudes from 0 to 20,000 m (66,000 ft) and instrument airspeeds from 0 to 1,300 km/h (810 mph); the system also includes a survival kit to assist the pilot after ejection.
One of the main technical goals of the PAK FA programme is to achieve total integration of avionics systems, or sensor fusion, increase the pilot's situational awareness and reduce workload. Integration of the Su-57's onboard systems is controlled by an IUS (Russian: ИУС, short for: Информационно-управляющая система, lit. 'Information Management System'), with its computer system developed by GRPZ from Ryazan. The main avionics systems are the Sh-121 (Russian: Ш-121) multifunctional integrated radio electronic system (MIRES) and the 101KS "Atoll" (Russian: 101КС "Атолл") electro-optical system. In a departure from prior Sukhoi aircraft, the IUS systems integration was performed by Sukhoi itself rather than RPKB of Ramenskoye. The integrated avionics suite, called IMA BK (Russian: ИМА БК, short for: Интегрированной модульной авионики боевых комплексов, lit. 'Integrated Modular Avionics Combat Systems'), uses fibre optic channels and runs on over 4 million lines of code.
The Sh-121 consists of the N036 Byelka radar system and L402 Himalayas electronic countermeasures (ECM) system. Developed by Tikhomirov NIIP Institute, the N036 consists of the main nose-mounted N036-1-01 X band active electronically scanned array (AESA) radar, or in Russian nomenclature, active phased array radar (Russian: АФАР, romanized: AFAR, short for: Активная фазированная антенная решётка), with 1,514 T/R modules and two side-looking N036B-1-01 X-band AESA radars with 404 T/R modules embedded in the cheeks of the forward fuselage for increased angular coverage. The nose antenna is tilted backwards for stealth. Moreover, the side-looking radar could enable the Su-57 to employ beaming tactics while still able to guide its own missile. The suite also has two N036L-1-01 L band transceivers on the wing's leading edge flaps that are not only used to handle the N036Sh Pokosnik (Reaper) friend-or-foe identification system but also for electronic warfare purposes. Processing of the X- and L-band signals by the N036YeVS and GRPZ Solo-21 computers enable the system's information to be significantly enhanced. The L402 Himalayas ECM suite made by the Kaluga Research Radio Engineering Institute uses both its own arrays and the N036 radar system, with one of its arrays mounted in the dorsal sting between the two engines. Redundant radio telephone communication and encrypted data exchange among various aircraft and also command centers (ground and sea-based and airborne) are provided by the S-111 system, developed by Polyot.
The UOMZ 101KS "Atoll" electro-optical system consisted of the 101KS-V infrared search and track (IRST), 101KS-O directional infrared counter measures (DIRCM), 101KS-U ultraviolet missile approach warning sensors (MAWS), 101KS-P thermal imager for low altitude flight and landing, and 101KS-N navigation and targeting pod. The IRST turret is mounted on the starboard side in front of the cockpit and can track multiple targets simultaneously. When not in use, the receiver is turned backwards and its rear is treated with RAM to preserve stealth. Additionally, the Su-57 is the first fighter to mount a DIRCM system, with one turret mounted behind the canopy and another mounted under the cockpit. The aircraft is capable of deploying countermeasures such as flares and radar decoys, as well as single-use programmable ECM transmitters. The dispensers for these countermeasures are mounted in the tail boom between the engines.
For in-flight navigation, the Su-57 uses the BINS-SP2M inertial navigation system developed by Concern Radio-Electronic Technologies (KRET). The system can also integrate with GLONASS, and is controlled by the IVS-50 computing system. In 2016, KRET announced it is developing a multifunctional video processing system called "Okhotnik" (Hunter) to increase the Su-57's target detection range as well as to improve automatic detection and tracking of targets. A monitoring system allows real-time assessment of the aircraft's condition and predict the remaining 'life' of the composite parts of the aircraft by transmitting information through optical fibers, with sensitivity to mechanical influences, woven into the structure. This allows a more efficient maintenance and repair process. The Su-57 could also serve as a testbed for advanced AI and man-unmanned teaming technologies intended for use in a future sixth-generation fighter program. The aircraft has also tested autonomous flight without pilot input.
Testing and trials
Even before the first flight of the T-50 prototype, several subsystems were tested on other aircraft for validation and risk reduction; an Su-27M was used to test the AL-41F1 engine on 21 January 2010, while another tested the KSU-50 flight control system. The T-50 prototype conducted its first high speed taxi run on 21 January 2010 and had its maiden flight several days later on 29 January 2010. First supersonic flight occurred on 14 March 2011 at a test range near Komsomolsk-on-Amur.
The Su-57 tests consisted of preliminary trials PI (Russian: ПИ, short for: Предварительные испытания) conducted by Sukhoi at the Gromov Flight Research Institute (LII) (Russian: ЛИИ) at Zhukovsky, as well as two stages of joint state trials GSI (Russian: ГСИ, short for: Государственные совместные испытания) conducted by the Ministry of Defence at the 929th State Flight Test Centre (GLITs) (Russian: ГЛИЦ) at Akhtubinsk. The completion of GSI-1 resulted in the acceptance of the aircraft's airworthiness, and the completion of GSI-2, which tests the mission systems and armaments, clears the Su-57 for operational service. The preliminary trials and state trials occurred with some overlap with each other.
Early flight tests revealed that the initial T-50 design had problems with structural strength and fatigue; when the first two prototypes were showcased publicly in MAKS 2011, the airframes cracked despite flying with a restrictive 5–g limit, which necessitated grounding and structural reinforcing for over a year as well as a “second stage” structural redesign. Of the ten flying and three non-flying T-50 prototypes, the three non-flying prototypes tested static flight loads, one each for "first stage" and "second stage" structures, and avionics integration. The first two flying prototypes tested flight characteristics and basic mechanical systems, and thus had no mission systems. Testing of mission systems such as the radar and electronic warfare suite began from the third prototype onwards, with each subsequent aircraft having slight variations in the arrangement of avionics and sensor systems. The final pre-production aircraft were equipped with full mission systems and tested the overall integrated avionics.
By February 2014, the first phase of preliminary trials, PI-1, had concluded;[N 10] in the same month, the 929th GLITs received its first T-50 at Akhtubinsk for further testing and GSI state trials. However, severe issues were discovered during PI-1; in addition to the structural issues, the aircraft suffered from engine problems, including the AL-41F1 compressor stall during the MAKS 2011 airshow. In June 2014, the fifth prototype was severely damaged by an in-flight fire and written off, and an incomplete "first stage" airframe was finished using parts salvaged from the fifth prototype.[N 8] Both preliminary and state trials were delayed by the fire and the structural redesign; the second phase of preliminary trials, PI-2, ran from 2014 to 2019 and mainly used structurally reinforced "first stage" aircraft while GSI-1 was halted until 2016 in order to wait for the updated "second stage" airframes. Armament trials were also delayed, with external weapon trials starting in May 2014 and internal trials starting in March 2016. GSI-1 was finished on 8 February 2018 with formal signing in May 2018. After more than 3,500 flights, GSI-2 was planned to be completed by 2019, but this was pushed to 2020, partly because of the crash of the first production aircraft in December 2019.
As the Su-57 is gradually being inducted into Russian military service, Sukhoi is testing upgrades for the improved Su-57M variant. First flight of the izdeliye 30 engine occurred on 5 December 2017 with the second prototype (T-50-2, bort no. 052). Prototypes were also used for unmanned aerial vehicle (UAV) teaming tests with the Okhotnik UCAV, with a video of flight tests released by the Ministry of Defence on 27 September 2019. On 28 June 2020, TASS, with reference to anonymous sources within the military-industrial complex, reported that a 'swarm' teaming experiment had been conducted with a group of Su-35s and an Su-57 acting as a command and control aircraft. The networked information exchange significantly increases the efficiency of combat missions. Reportedly, the experiment was conducted in "real combat conditions."
Syrian combat evaluation
On 21 February 2018, two Su-57s performed their first international flight as they were spotted landing at the Russian Khmeimim air base in Syria. The aircraft were deployed along with four Sukhoi Su-35 fighters, four Sukhoi Su-25s, and one Beriev A-50 AEW&C aircraft. Three days later two more Su-57s were reported to have arrived in Syria. The deployment was criticised by some experts as overly risky, especially after reports of drone attacks at Khmeimim air base, as well as having limited value due to the short duration of only several days. As the deployment overlapped with Russia's Defender of the Fatherland Day, the purpose may have been to support the president's state-of-the-nation speech. Additionally, deployment of the aircraft in a combat theatre may serve to enhance the aircraft's marketing. On 1 March 2018, the Russian Defence Minister Sergey Shoygu confirmed that the two Su-57s indeed spent two days in Syria and successfully completed a trials program, including combat trials during which parameters of weapons work were monitored. On 25 May 2018, the Defence Ministry disclosed that during the February 2018 deployment to Syria, a Su-57 fired a cruise missile in combat, likely a Kh-59MK2. On 18 November 2018, the Defence Ministry posted an extended video of the fighters' flights, and announced that Su-57 performed 10 flights during its deployment to Syria. However, the video did not specify when the test flights took place.
On 18 December 2019, the Chief of the Russian General Staff, Valery Gerasimov said that Russian Defence Ministry has once again tested the Su-57 in Syria, and all tasks have been successfully fulfilled.
Entry into service
On 25 December 2020, the Russian Defence Ministry announced the introduction of the first serial multifunctional fifth generation fighter Su-57 which entered service with one of the aviation regiments of the Southern Military District.The first fully operational Su-57 regiment of 24 aircraft is expected to be equipped by 2025.
Russian sources claim that Su-57 fighters were used two or three weeks after the start of the 2022 Russian invasion of Ukraine, striking targets with missiles outside of the zone of activity of Ukrainian air defenses. Other Russian aircraft are also restricted mainly to Russian airspace.
In the early stages of the PAK FA programme, India had planned to be one of the largest foreign customers by procuring the FGFA derivative. It originally planned on buying 166 single-seat and 48 two-seat fighters, but later changed it to 214 single-seat fighters, and later reduced its purchase to 144 fighters by 2012. In April 2018, India pulled out of the FGFA project, which it believed did not meet its requirements for stealth, combat avionics, radars and sensors by that time. Indian Air Force Air Chief Marshal Birender Singh Dhanoa, during an interview with Russian Ministry of Defence's official newspaper Krasnaya Zvezda (Red Star), stated that the Su-57 is currently not being considered for the service, but the combat aircraft can be evaluated once it joins active service with the Russian Air Force. The General Director of the United Aircraft Corporation Yuri Slyusar however denied the previous reports saying "the topic is not closed" and that Russia and India are still discussing the creation of the fifth-generation fighter. However, in October 2019, the Indian Air Force Chief of Air Staff RKS Bhadauria stated that the country will not be importing stealth fighters like the Su-57, and will instead focus on indigenous efforts such as the HAL AMCA.
Sukhoi states that the main export advantage of the PAK FA is its lower cost than current US fifth generation jet fighters. Russia was reported to be offering the PAK FA for South Korea's next generation jet fighter. South Korea's defence procurement agency confirmed that the Sukhoi PAK FA was a candidate for the Republic of Korea Air Force's next-generation fighter (F-X Phase 3) aircraft; however, Sukhoi did not submit a bid by the January 2012 deadline. In 2013, Russia offered Brazil participation and joint production in a next-generation fighter based on the Su-57. Instead of Russian Su-57 and French Rafale, Brazil signed an agreement with the Swedish Saab Group to locally produce 36 Gripen E fighters for the Brazilian Air Force.
In May 2019, as Turkish participation in the F-35 program was in doubt due to Turkey's procurement of the S-400 missile system, CEO of Rostec Sergey Chemezov said that Russia was ready to cooperate with Turkey on the export and local production of the Su-57. On 14 September 2019, an Su-57 took part in the 2019 Technofest festival held in Istanbul. However, on 7 February 2020, President Erdogan announced that the replacement of the F-35 will not be Russian Su-57, but instead will be the Turkish domestic fifth-generation aircraft TF-X fighter.
On 27 December 2019, Algeria reportedly signed a contract for 14 aircraft as part of large military deal that also includes the purchase of Su-34 and Su-35 fighters. The decision was reportedly taken in summer 2019, when Algerian delegation personally inspected the Su-57 at the 2019 MAKS air show. Once Sukhoi fulfill domestic delivery commitment, Algeria set to receive the first Su-57E in 2028.
It has been reported that Vietnam may become a customer of the Su-57. The country is expected to acquire the fighters to replace its aging fleet of 11 Su-27s. On 9 July 2021, Vietnam announced its intention to buy Su-57 aircraft, but it is critical of the aircraft's workmanship.
Russia has offered Su-57E fighters to the United Arab Emirates during IDEX 2021. During the 2019 Dubai Air Show, Chemezov talked about the possibility of "localization" of portions of the Su-57 supply chain within other countries that decide to buy those jets, including "…United Arab Emirates, India or Turkey…", depends on the capabilities of the defense industrial base of the customer in question. However, the UAE has refrained from signing a contract with Russia to avoid CAATSA sanctions from the United States.
Iraqi military leadership including its inspector for the Iraqi Ministry of Defence Imad Al-Zuhairin stated the country's interest in the Su-57.
Su-57 is the first production variant for the Russian Aerospace Forces. Flight testing began with the T-50 prototype in 2010, and serial production began in 2019. A total of three regiments, 76 aircraft, are planned with the first aircraft delivered in December 2020.
Su-57E is the export version of Su-57. On 28 March 2019, The aircraft first promoted to international customers during the 2019 Langkawi International Maritime and Aerospace Exhibition. The aircraft was officially unveiled at the 2019 MAKS International Aviation and Space Salon in Moscow on 28 March 2019. Rosoboronexport is marketing the aircraft as Perspective multirole fighter (PMF).
Su-57M is an upgraded variant of the base Su-57 under the program name Megapolis, and incorporates improved mission systems, reliability and maintenance enhancements, new flight control actuators, and the Saturn izdeliye 30 engines. Flight testing is planned to begin in 2022, and serial production is planned for the mid-2020s.
Sukhoi/HAL FGFA was a planned version of Su-57 for Indian Air Force but India withdrew from the FGFA programme in 2018 before any prototype was built. The FGFA was intended to be the primary export version of the PAK FA and was to differ in 43 ways with improvements to stealth, supercruise, sensors, networking, and combat avionics. There were conflicting reports on the FGFA, with India detailing numerous improvements over the baseline PAK FA, while Mikhail Pogosyan, the head of United Aircraft Corporation, said in 2013 that the PAK FA and the FGFA will use "identical onboard systems and avionics". India has refrained from signing a deal with Russia citing concerns of aircraft's stealth, radar and supercruise capability in 2014 and ultimately withdrew from the programme in 2018.
In 2008, UAC president Alexei Fedorov has said that any decision on applying fifth-generation technologies to produce a smaller fighter (comparable to the F-35) must wait until after the development of the PAK FA is completed.
A naval version of the Su-57 was proposed for the Project 23000E or Shtorm supercarrier. Models of the aircraft carrier project are showing Su-57 on board, with folding wings and stabilators. The Su-57 should be able to use the takeoff ramp as well as the Electromagnetic Aircraft Launch System. The draft of the future state armament program (GVP) for 2024–2033 includes the development of a new carrier-based fighter based on the Su-57, albeit with deep modifications.
The aircraft is used as a testbed for integration with UAVs as well as various subsystems (including weapon, control and navigation systems) being developed for Russia's future sixth-generation combat system, both in manned and unmanned version. In January 2019, it was reported the third flyable Su-57 prototype (bort. no 053) is being used for interaction with the Sukhoi S-70 Okhotnik UCAV, and testing of its avionics systems.
In July 2021, it was officially announced that a two-seater variant of the Su-57 was under development, to be used for training pilots and for ensuring the control of the Sukhoi S-70 Okhotnik UCAV.
- Russian Aerospace Forces
On 10 June 2014, the fifth flying prototype, aircraft T-50-5, was severely damaged by an engine fire after landing. The pilot managed to escape unharmed. The aircraft was subsequently written off, and its salvageable parts were cannibalized to finish the sixth "first stage" prototype, which was then given the fifth prototype's bort number and its designation changed from T-50-6-1 to T-50-5R. However, official accounting still considers the two aircraft to be the "same" one.
On 24 December 2019, the first serial Su-57 (bort number "01 blue") crashed 110–120 km away from the Dzyomgi Airport, Khabarovsk Krai, during the final stage of its factory trials due to a control system malfunction. The pilot ejected and was recovered by helicopter. According to TASS, the test flight took place at an altitude of 8,000 meters when the malfunction occurred, causing the airplane to enter a rapid spiral descent. When all attempts to stabilize the airplane into a horizontal flight using the manual flight control system failed, the pilot ejected at an altitude of 2,000 meters.
- Crew: 1
- Length: 20.1 m (65 ft 11 in)
- Wingspan: 14.1 m (46 ft 3 in)
- Height: 4.6 m (15 ft 1 in)
- Wing area: 78.8 m2 (848 sq ft)
- Empty weight: 18,000 kg (39,683 lb)
- Gross weight: 25,000 kg (55,116 lb) normal takeoff weight, 29,270 kg (64,530 lb) at full load
- Max takeoff weight: 35,000 kg (77,162 lb)
- Fuel capacity: 10,300 kg (22,700 lb)
- Powerplant: 2 × Saturn AL-41F1 afterburning turbofan, 88.3 kN (19,900 lbf) thrust each dry, 142.2 kN (32,000 lbf) with afterburner, 147.1 kN (33,100 lbf) in emergency power
- Maximum speed: Mach 2 (2,135 km/h; 1,327 mph) at altitude
- Mach 1.3 (1,400 km/h; 870 mph) supercruise at altitude
- Range: 3,500 km (2,200 mi, 1,900 nmi) subsonic, 4,500 km from 2 outboard fuel tanks
- Supersonic range: 1,500 km (930 mi, 810 nmi)
- Service ceiling: 20,000 m (66,000 ft)
- g limits: +9.0
- Wing loading: 371 kg/m2 (76 lb/sq ft) normal takeoff weight
- Thrust/weight: 1.16 at normal takeoff weight (0.99 at loaded weight with full fuel)
- Guns: 1 × 30 mm Gryazev-Shipunov GSh-30-1 autocannon
- Hardpoints: 12 hardpoints (6 × internal, 6 × external)
- Sh-121 multifunctional integrated radio electronic system (MIRES)
- 101KS Atoll electro-optical targeting system
Notable appearances in media
Aircraft of comparable role, configuration, and era
- Date of first operational aircraft in military service; first operational Su-57 regiment is to be equipped by 2025.
- Russia established the Russian Aerospace Forces (VKS) as a new branch of its military on 1 August 2015 with the merging of the Russian Air Force (VVS) and the Russian Aerospace Defence Forces (VVKO).
- At the time, there was a planned fleet of one-third MFI and two-thirds LFI.
- In the late 1990s, as the status of MFI declined, conceptual work for a next generation fighter was conducted under the LFS (Russian: ЛФС, short for: Лёгкий фронтовой самолёт, romanized: Lyogkiy Frontovoy Samolyot, lit. 'Light Frontline Aircraft') until efforts shifted to the PAK FA.
- While Sukhoi tested forward-swept wings with the Su-47, Soviet and Russian research indicated that such configuration was mainly beneficial at transonic speeds and loses out to conventionally swept wings at supersonic speeds. The forward-swept wing was not chosen for the T-50.
- Yakovlev would only participate as a subcontractor for the potential short takeoff and vertical landing (STOVL) module in the future.
- The Russian term изделие, translit. izdeliye literally means "manufactured article" or "product".
- The originally planned sixth flying prototype, T-50-6-1, was to be the last "first stage" airframe. After the fifth prototype, T-50-5, was involved in a fire accident, T-50-6-1 was completed using parts salvaged from the written-off T-50-5 and was renamed T-50-5R, carrying the same "055" bort number. While it is essentially a new and distinct airframe, official accounting still considers the two airframes to be the “same”, with the R (Russian: Р) short for: ремонтый, lit. 'repair'. The sixth flying prototype T-50-6-2, the first "second stage" aircraft, was given the "056" bort number.
- The initial maximum speed requirement was Mach 2.35 at high altitude, but this was reduced to Mach 2.15 and then to Mach 2.0 in 2006 order to increase the amount of composites used in the airframe.
- Conclusion of PI-1 in February 2014 saw envelope expansion to Mach 1.7, instrument airspeed of 1,000 km/h (620 mph), ceiling of 14,000 m (46,000 ft), and g-load of 6.5.
- The new fighter's control systems, avionics and cockpit will be designed on the basis of the Su-35BM's systems.
- "Russia draws back veil of secrecy with peek at future fighter". RIA Novosti. 29 January 2010. Archived from the original on 10 May 2013. Retrieved 4 March 2019.
- "Первый серийный истребитель Су-57 поступил в авиаполк Южного военного округа".
- "Совершил первый полет последний Су-57, — источник". News.rambler.ru. Archived from the original on 26 December 2017. Retrieved 3 January 2018.
- "В Новосибирске замечены два новых истребителя Су-57". avia.pro. 28 May 2022.
- "NATO assigns new reporting name for Su-57 5th generation jet fighter". ruaviation.com. 1 November 2019. Retrieved 2 November 2019.
- "Russia's 5th-generation fighter jet named as Su-57". TASS. Archived from the original on 12 August 2017. Retrieved 11 August 2017.
- "Sukhoi Company launches flight tests of PAK FA advanced tactical frontline fighter". Sukhoi.org (Press release). 29 January 2010. Archived from the original on 1 May 2011. Retrieved 26 January 2011.
- Cohen, Ariel (16 January 2009). "Russia bets on new Sukhoi fighter to match F-35". United Press International. Archived from the original on 5 February 2010. Retrieved 11 January 2010.
- Druzhinin, Alexei. "Russian Air Force to buy over 60 fifth-generation fighters". RIA Novosti. Archived from the original on 5 August 2010. Retrieved 26 January 2011.
- Butowski (2021), p. 5
- Gordon 2021, p. 7
- Gordon, Yefim (2002). Sukhoi S-37 and Mikoyan MFI: Russian Fifth-Generation Fighter Technology Demonstrators. Warbird Tech. Vol. 1. Hinckley, UK: Midland Publishing. ISBN 1-85780-120-2.
- Butowski (2021), pp. 21–22
- Gordon 2021, pp. 95–96
- Butowski (2021), pp. 22–24
- Gordon 2021, pp. 96–97
- Butowski, p. 13
- Butowski (2021), p. 25
- "Russia to test PAK-FA in 2007". Information Telegraph Agency of Russia. 8 June 2005.
- "Premier Putin satisfied with Russian fifth-generation fighter tests". RIA Novosti. 20 April 2010. Archived from the original on 10 May 2013. Retrieved 20 April 2010.
- Butowski, Piotr (1 November 2006). "MiG's Fifth Generation Fighter Builds up New Momentum". Russia & CIS Observer. Archived from the original on 14 May 2018. Retrieved 14 May 2018.
- Butowski (2021), p. 26
- Perry, Dominic (10 June 2014). "Fire damages PAK-FA prototype on landing". FlightGlobal. Archived from the original on 14 June 2014. Retrieved 12 June 2014.
- "KnAAPO PAK FA information page". Archived from the original on 8 March 2014. Retrieved 23 June 2014.
- Butowski (2021), p. 16
- Butowski, Piotr (22 June 2004). "Halfway to PAK FA: the latest addition to the Su-27 family seeks to bridge the gap to the fifth generation combat aircraft". Interavia Business & Technology. Aerospace Media Publishing – via HighBeam Research (subscription required). OCLC 71365085. Archived from the original on 24 September 2015. Retrieved 19 April 2013.
- Butowski, Piotr (22 September 2007). "Wraps come off new Russian fighters: Russia's so-called "intermediate-generation" fighters made their debut at MAKS 2007". Interavia Business & Technology. Aerospace Media Publishing – via HighBeam Research (subscription required). OCLC 71365085. Archived from the original on 5 November 2013. Retrieved 19 April 2013.
- Коц, Андрей (8 August 2017). "Эволюция ПАК ФА. Как менялся российский истребитель пятого поколения" (in Russian). RIA Novosti. Archived from the original on 11 August 2017. Retrieved 12 August 2017.
- "Russia to build fifth-generation fighter prototype soon". RIA Novosti. 8 August 2007. Archived from the original on 16 August 2007. Retrieved 8 August 2007.
- "Russia's next-generation warplane to make maiden flight in 2009". RIA Novosti. 21 January 2009. Archived from the original on 18 May 2013. Retrieved 26 January 2009.
- Butowski (2021), p. 54
- "The contract to develop a sketch and technical project of the Russian-Indian 5th -generation fighter was completed". Sukhoi.org (Press release). Archived from the original on 5 October 2013. Retrieved 16 November 2013.
- "India, Russia to ink new military pact". The Times of India. 10 October 2009. Archived from the original on 5 July 2013. Retrieved 11 May 2013.
- "India, Russia to Ink gen-5 fighter pact". Business Standard. Archived from the original on 6 October 2012. Retrieved 19 November 2012.
- "Medvedev Flair Firms Up Indo-Russian Relations". Observer Research Foundation. 29 December 2010. Archived from the original on 9 September 2012. Retrieved 18 May 2012.
- "India withdraws from FGFA project, leaving Russia to go it alone". Jane's 360. 20 April 2018. Archived from the original on 23 May 2018.
- Halpin, Tony (30 January 2010). "Russia unveils its first stealth fighter jet – the Sukhoi T-50". The Times. Archived from the original on 4 June 2011. Retrieved 7 February 2010.
- "Sukhoi PAK FA Updates: First Prototype by August 2009, Special Software for Indian Versions". India Defence. 28 February 2009. Archived from the original on 4 March 2009. Retrieved 13 March 2009.
- Solovyov, Dmitry (20 August 2009). "Interview: Russia's new fighter to fly by yr-end – Sukhoi". Reuters. Archived from the original on 16 January 2010. Retrieved 20 August 2009.
- "Russia to start 5th generation fighter tests in 2010 – deputy PM". RIA Novosti. 8 December 2009. Archived from the original on 13 December 2009. Retrieved 8 December 2009.
- "Начались испытания российского истребителя пятого поколения" [Russian fifth-generation fighter tests have begun]. Lenta.ru. 24 December 2009. Archived from the original on 27 December 2009. Retrieved 26 December 2009.
- "Sukhoi fifth-generation fighter taxiing". BBC Russian Service. 24 December 2009. Archived from the original on 13 January 2010. Retrieved 30 December 2009.
- Reed Business Information Limited. "PICTURES & VIDEO: Sukhoi's PAK FA fighter completes first flight". FlightGlobal. Archived from the original on 16 February 2014. Retrieved 14 November 2014.
- Pandit, Rajat. "1st test of 5-Gen fighter in Russia". The Times of India. Archived from the original on 29 March 2012. Retrieved 26 January 2011.
- "Russia tests 2nd prototype of fifth-generation fighter". RIA Novosti. 2011. Archived from the original on 5 March 2011. Retrieved 3 March 2011.
- "Fifth PAK FA fighter aircraft made its first flight in Komsomolsk-on-Amur". Sukhoi.org (Press release). 28 October 2013. Archived from the original on 11 November 2013. Retrieved 16 November 2013.
- "Т-50 – Альбомы" (in Russian). KnAAPO. Archived from the original on 13 August 2017. Retrieved 12 August 2017.
- Butowski (2021), p. 44
- bmpd (31 July 2017). "Как сообщается, серийный вариант истребителя Т-50 получил официальное наименование Су-57". bmpd. Archived from the original on 25 February 2018. Retrieved 6 December 2018.
- Gordon (2021), pp. 193–197
- Butowski, Piotr. "Putin's Raptorski". Air International, Vol. 93, No 3, September 2017, pp. 24–27. Stamford, UK: Key Publishing.
- Ведмеденко, Илья (7 August 2017). "Новый экземпляр Су-57 совершил свой первый полет, — источник". Naked Science (in Russian). Archived from the original on 7 August 2017. Retrieved 12 August 2017.
- Butowski (2021), p. 45
- Sysoev, Grigoriy (13 February 2012). "Russia to Increase Number of 5G Fighters in Test Flights". RIA Novosti. Archived from the original on 17 April 2012. Retrieved 16 October 2014.
- "PAK FA – Russia Special Report". FlightGlobal. 2 August 2011. Archived from the original on 28 May 2014. Retrieved 10 May 2014.
- "Sukhoi: Development of PAK FA is going on without any failures" Archived 23 October 2014 at the Wayback Machine Russian Aviation, 28 July 2011.
- Butowski (2021), p. 58
- Druzhinin, Alexei. "Russian military to buy 60 fifth-generation fighters after 2016". RIA Novosti. Archived from the original on 5 August 2010. Retrieved 26 January 2011.
- Safronov, Ivan (25 March 2015). "Russian Air Force to buy fewer PAK FA fighter aircraft". Russia & India Report. Archived from the original on 27 July 2015.
- Sweetman, Bill (21 December 2013). "T-50 Update". Aviation Week. Archived from the original on 28 May 2014. Retrieved 24 May 2014.
- Majumdar, Dave (16 February 2017). "Russia's Fearsome PAK-FA Stealth Fighter Will Enter Service in 2018". The National Interest. Archived from the original on 9 April 2017. Retrieved 9 April 2017.
- "Первый контракт на поставку истребителей Су-57 заключат в ближайшее время" (in Russian). Archived from the original on 1 July 2018. Retrieved 30 June 2018.
- Karnozov, Vladimir. "Russia Places Initial Production Order for Stealth Fighter". Aviation International News Online. Archived from the original on 13 July 2018. Retrieved 13 July 2018.
- "ЛИПЕЦКИЙ АВИАЦЕНТР СКОРО ПОЛУЧИТ ИСТРЕБИТЕЛИ ПЯТОГО ПОКОЛЕНИЯ СУ-57". RIA Novosti. 14 July 2018. Archived from the original on 21 July 2018. Retrieved 21 July 2018.
- "Первые истребители Су-57 готовы к отправке в войска". Russia-24. 30 June 2018. Archived from the original on 21 July 2018. Retrieved 21 July 2018.
- Gady, Franz-Stefan. "Russia Will Not Mass-Produce 5th Generation Stealth Fighter Jet". The Diplomat. Archived from the original on 13 July 2018. Retrieved 21 July 2018.
- Lockie, Alex. "Russia admits defeat on its 'stealth' F-35 killer by canceling mass production of the Su-57 fighter jet". Business Insider. Archived from the original on 17 July 2018. Retrieved 21 July 2018.
- "Минобороны и "Сухой" заключили контракт на поставку двух Су-57". TASS. 22 August 2018. Archived from the original on 23 August 2018. Retrieved 23 August 2018.
- "Источник: контракт на поставку 13 Су-57 для ВКС России планируется подписать в 2020 году". TASS. 15 January 2019. Archived from the original on 16 January 2019. Retrieved 17 January 2019.
- "Putin says 76 Su-57 jets to be purchased before 2028". TASS. 15 May 2019. Archived from the original on 17 May 2019. Retrieved 18 May 2019.
- "Минобороны получит 76 истребителей Су-57". TASS. 27 June 2019. Retrieved 28 June 2019.
- "Russian Defense Ministry to get 76 Su-57 fighter jets". TASS. 27 June 2019. Retrieved 28 June 2019.
- "На "Армии-2019" подписаны контракты на боеприпасы для Су-57". TASS. 27 August 2019. Retrieved 17 November 2019.
- "Russia launches serial production of Su-57 fifth-generation fighter jet". TASS. 29 July 2019. Retrieved 25 December 2020.
- "Тяжёлый Ударный Беспилотный Летательный Аппарат "Охотник"" (in Russian). bastion-opk.ru. Retrieved 9 January 2020.
- Butowski (2021), p. 89
- "Небесная электромеханика: Су-57 получит новейшие системы управления". Izvestia (in Russian). 27 April 2020. Retrieved 2 May 2020.
- "Russia tries something different – an 'electric' Su-57 fighter jet". bulgarianmilitary.com. 27 April 2020. Retrieved 2 May 2020.
- "Шойгу заявил, что боевые возможности российской армии за 2020 год возросли на 13%". TASS. 21 December 2020. Retrieved 25 December 2020.
- Donald, David (20 July 2021). "New Sukhoi Fighter Design Unveiled at MAKS". Aviation International News.
- "Sukhoi Unveils Export-Oriented Light Fighter". Aviation Week. 22 July 2021.
- "U.S. Treasury Sanctions Russia's Defense-Industrial Base, the Russian Duma and Its Members, and Sberbank CEO". U.S. Department of the Treasury. Retrieved 29 April 2022.
- Seoul, Yang Jie in Tokyo and Jiyoung Sohn in (19 March 2022). "Chip Sanctions Challenge Russia's Tech Ambitions". The Wall Street Journal. ISSN 0099-9660. Retrieved 29 April 2022.
- "Here's What the New, Tightened SWIFT Sanctions on Russian Banks Actually Do". Time. Retrieved 29 April 2022.
- Karnozov, Vladimir (29 January 2010). "Sukhoi's PAK FA fighter completes first flight". FlightGlobal. Archived from the original on 16 February 2014. Retrieved 1 February 2010.
- RU 2440916 C1, "Самолет интегральной аэродинамической компоновки, Airplane with integral aerodynamic configuration (Sukhoi patent on T-50 configuration)", published 2012-01-27
- Sweetman, Bill. "New moves". Aviation Week and Space Technology, 10 August 2013. p. 43.
- RU 2503584, "Маневренный самолет (Maneuverable aircraft)" Archived 26 June 2015 at the Wayback Machine
- Sweetman, Bill (19 August 2013). "Sukhoi T-50 Shows Flight-Control Innovations". Aviation Week. Archived from the original on 20 October 2013. Retrieved 16 November 2013.
- Gordon 2021, pp. 312
- "Su-57 Felon – Materials". Global Security.
- Lake 2010, pp. 26–33.
- Butowski (2021), p. 67
- "2 new videos show Russian Su-57s fighters landing at the same time and performing flat spins". Business Insider. 27 November 2018. Archived from the original on 30 November 2018. Retrieved 30 November 2018.
- Butowski (2021), p. 27
- Butowski, Piotr. "T-50 Turning and Burning over Moscow". Air International. Vol. 85, no. 4 October 2013. Stamford, UK: Key Publishing. pp. 79–82.
- "Mikhail Pogosyan: T-50 will Provide Reliable Protection Boundaries" Archived 24 October 2014 at the Wayback Machine. AviaPort.ru, 20 May 2013. Retrieved 15 July 2014.
- RU patent RU2502643C2, "Многофункциональный самолет с пониженной радиолокационной заметностью (Multifunctional aircraft with reduced radar signature)", published 27 December 2013
- "PAK FA stealth features patent published". Jane's Information Group. 10 January 2014. Archived from the original on 23 October 2014. Retrieved 21 July 2018.
- RU patent RU2623031C1, "Воздухозаборник самолета (Aircraft air intake)", published 2017-06-21, issued 2017-06-21
- "Russia's 5th-generation fighter jet gets advanced stealth coating". TASS. 11 January 2019. Archived from the original on 15 January 2019. Retrieved 14 January 2019.
- Hunter, Jamie. "Check Out These Images Of Russia's Second Su-57 Felon Fighter Under Construction". The War Zone. Retrieved 18 October 2020.
- Butowski, Piotr. "Russian Supercruiser". Air International, February 2011, p. 34. Stamford, UK: Key Publishing.
- RU 2502643, "Многофункциональный самолет с пониженной радиолокационной заметностью (Multifunctional aircraft with reduced radar signature)"
- Plopsky, Guy and Fabrizio Bozzato. "The F-35 vs. The VHF Threat" Archived 26 December 2014 at the Wayback Machine. The Diplomat, 21 August 2014.
- Ralston, J; Heagy, J; et al. "Environmental/Noise Effects on UHF/VHF UWB SAR" Archived 2 January 2015 at the Wayback Machine. dtic.mil, September 1998. Retrieved 2 January 2015.
- "NPO." Archived 1 February 2010 at the Wayback Machine Saturn Press Release, 29 January 2010. Retrieved 26 January 2011.
- Butowski (2021), p. 73
- Butowski, Piotr (October 2019). "The Final Flanker; Russian Fifth-Gen". Air International. London: Key Publishing. Retrieved 12 April 2020.
- Shukla, Ajai. "Russia can't deliver on Fifth Generation Fighter Aircraft: IAF". Archived 21 October 2014 at the Wayback Machine business-standard.com, 21 January 2014.
- Butowski, Piotr (6 January 2020). "Future Of Su-57 Next-Generation Engine Uncertain". Aviation Week.
- "Russian Air Force to Receive the First Production Su-57 in 2018 – Defense Update". Defense-update.com. 17 December 2017. Archived from the original on 21 December 2017. Retrieved 18 December 2017.
- RU 2614871, "Грузовой отсек самолета (Aircraft cargo hold)", published 24 June 2015, issued 10 January 2017
- Butowski, Piotr. Russia and CIS Observer. 17 June 2007.
- "Vympel plans to develop air-to-air missiles for Russia's PAK FA fighter". Jane's Missiles and Rockets. 19 May 2006
- "PAK FA will complement digital missiles" Archived 22 October 2014 at the Wayback Machine. Machine Resource i-mash.ru (RU), 3 December 2013. Retrieved 4 April 2014.
- Tahar, Abraham Ait (26 May 2018). "The Su-57 is Only as Dangerous as its Best Missile; Why the K-77 Will be a Game Changer for the Russian Air Force". Military Watch Magazine. Retrieved 27 August 2019.
- Barrie, Douglas and Pyadushkin, Maxim. "R-77, R-73 Missile Upgrades Emerge". Aviation Week. 13 August 2009
- "Report: Russia Has Developed Prototype of Air-to-Ground Hypersonic Missile for Su-57". The Diplomat. 25 February 2020. Archived from the original on 5 March 2020. Retrieved 13 March 2020.
- "Russia to Field Air-Launched Missiles for T-50 by 2014". RIA Novosti. 31 January 2012. Archived from the original on 4 February 2012. Retrieved 13 February 2012.
- "Истребитель пятого поколения Су-57 получит на вооружение гиперзвуковую ракету". bmpd.livejournal.com. 7 December 2018. Retrieved 27 December 2018.
- "Российский самолет пятого поколения Т-50 получит улучшенную авиапушку". vpk.name. Archived from the original on 7 April 2015. Retrieved 1 April 2015.
- "Video of live fire tests of the Russian T-50 stealth fighter's 30 mm gun appears online". The Aviationist. 18 September 2016. Archived from the original on 30 November 2018. Retrieved 30 November 2018.
- Butowski (2021), p. 76
- Trimble, Stephen (2 March 2010). "Sukhoi reveals T-50 cockpit layout and static airframe". FlightGlobal. Archived from the original on 15 December 2013. Retrieved 28 March 2014.
- "PAK FA fighter was fitted with advanced oxygen supply system". – Russian Aviation Archived 23 October 2014 at the Wayback Machine, RuAviation.com, 19 July 2013
- "Катапультное кресло К-36Д-5". NPP Zvezda (in Russian).
- "Противоперегрузочный костюм "ППК-7"". NPP Zvezda (in Russian).
- Butowski 2021, pp. 78–82
- "Russia Completes Testing of Su-57 Avionics 'Complex' – Avionics". Avionics. 23 November 2018. Archived from the original on 30 November 2018. Retrieved 30 November 2018.
- "Sukhoi starts testing new IMA BK FMS on Russia's PAK FA fighter". airrecognition.com. Archived from the original on 30 November 2018. Retrieved 30 November 2018.
- Butowski (2021), pp. 78–79
- Rogoway, Tyler (30 April 2018). "No, The Su-57 Isn't 'Junk:' Six Features We like on Russia's New Fighter". The War Zone. Archived from the original on 30 November 2018. Retrieved 30 November 2018.
- "Новейший российский истребитель получил один из ключевых элементов" [The newest Russian fighter got one of the key elements]. RIA Novosti. 24 April 2013. Archived from the original on 28 April 2014. Retrieved 29 April 2014.
- "Certification tests of the communication system for Su-57 will be completed this year - News - Russian Aviation". ruaviation.com. Retrieved 30 January 2019.
- "Communication equipment for Sukhoi-57 jet to be completed in 2017". TASS. Archived from the original on 30 December 2017. Retrieved 18 December 2017.
- "Sukhoi-57's Targetting Pod 101KS-N Spotted". Global Defence Watch. Archived from the original on 3 December 2018.
- Rogoway, Tyler. "Su-30s Acted As Infrared "Heat Traps" For Putin's Arrival in Syria Aboard A Tu-214PU". The War Zone. Archived from the original on 3 December 2018. Retrieved 3 December 2018.
- Butowski (2021), p. 83
- "Sukhoi T-50 Aircraft To Get New Navigation System". defenseworld.net. Retrieved 1 December 2019.
- "КРЭТ разрабатывает новейшую систему обнаружения целей для ПАК ФА". RIA Novosti. 29 July 2016. Archived from the original on 21 February 2019. Retrieved 21 February 2019.
- "KRET develops new Okhotnik target detection system for Russia's PAK FA fighter jet". airrecognition.com. 1 August 2016. Archived from the original on 21 February 2019. Retrieved 21 February 2019.
- "В России разработали "нервную систему" для самолетов будущего". RIA Novosti. 11 July 2017. Archived from the original on 8 December 2017. Retrieved 8 December 2017.
- "FPI presented a model of the 'nervous system' of the future fighter". Weaponews.com. Archived from the original on 8 December 2017. Retrieved 8 December 2017.
- "Источник: Су-57 отрабатывает беспилотный режим в ходе испытаний" (in Russian). RIA Novosti. 16 May 2020. Retrieved 16 May 2020.
- "Russia's Su-57 plane tests onboard systems for 6th-generation fighter jet — source". TASS. Retrieved 29 June 2020.
- Butowski (2021), p. 43
- "Russian air forces started the state testing of T-50 fighter". Russian Aviation. Archived from the original on 2 June 2014. Retrieved 28 May 2014.
- Butowski (2021), pp. 44–46
- Komarov, Alexey (8 March 2010). "Three More Sukhoi T-50 Prototypes To Fly in Next 12 Months". Aviation Week. Retrieved 30 January 2019.
- "Sukhoi Begins Testing Onboard Radar System for T-50 Aircraft". Sukhoi Company, 8 August 2012.
- Karnozov, Vladimir. "Sukhoi T-50 Moves to Radar, In-flight Refueling Tests" Archived 14 September 2014 at the Wayback Machine. Aviation International News, 31 August 2012.
- "Эволюция ПАК ФА. Как менялся российский истребитель пятого поколения". РИА Новости (in Russian). 8 August 2017. Archived from the original on 11 August 2017. Retrieved 30 November 2018.
- Gordon 2021, pp. 245–47
- "Russian Air Force Receives New Stealth Fighter Prototype". RIA Novosti. 21 February 2014. Archived from the original on 22 February 2014. Retrieved 21 February 2014.
- "Т-50-2 fighter aircraft made the flight to Akhtubinsk". Sukhoi.org (Press release). 21 February 2014. Archived from the original on 27 April 2014. Retrieved 5 March 2014.
- "Russia shows off Sukhoi T-50 stealth fighter". BBC News. 17 August 2011. Archived from the original on 5 April 2018.
- "This Is The First Video Of An Su-57 Firing A Missile From Its Side Weapon Bay, Or Is It?". The War Zone. 25 March 2020. Retrieved 26 March 2020.
- Butowski (2021), p. 86
- "Russia's defense ministry to sign contract for 12 Su-57 fighter jets". TASS. 8 February 2018. Archived from the original on 25 February 2018. Retrieved 24 February 2018.
- "Стали известны подробности испытаний Су-57". Rossiyskaya Gazeta. 30 March 2020. Retrieved 30 March 2020.
- "Russia's Su-57 fifth-generation fighter makes first flight with new engine". TASS. Archived from the original on 6 December 2017. Retrieved 6 December 2017.
- "VIDEO: Russia flies first Su-57 fitted with new Product 30 engine". FlightGlobal. 5 December 2017. Archived from the original on 8 December 2017. Retrieved 8 December 2017.
- "Russia's Okhotnik UAV makes first flight with Su-57". janes.com. 27 September 2019. Retrieved 27 September 2019.
- "Russian Su-57 Jet Controls Su-35 Aircraft 'Swarm' in Teaming Experiment". defenseworld.net. Retrieved 29 June 2020.
- "Russian Su-35s and Su-57s tested 'the flock' tactic in real combat conditions". bulgarianmilitary.com. Retrieved 29 June 2020.
- "Источники: Россия провела эксперимент по применению "роя" истребителей" (in Russian). TASS. 28 June 2020. Retrieved 29 June 2020.
- Seidel, Jamie. "Syria: Russian Su-57 stealth fighter spotter landing". News.com.au. Archived from the original on 22 February 2018. Retrieved 22 February 2018.
- СМИ сообщили о прибытии еще двух истребителей Су-57 в Сирию Archived 25 February 2018 at the Wayback Machine RIA Novosti, 24 February 2018.
- Gordon 2021, pp. 280–81
- Butowski (2021), p. 50
- Переброска Су-57 в Сирию несет в себе значительный риск Archived 24 February 2018 at the Wayback Machine vz.ru, 22 February 2018.
- Trevithick, Joseph. "Russia Releases First Official Video of Its Su-57s on Their Absurdly Short Trip To Syria". The War Zone. Archived from the original on 30 November 2018. Retrieved 30 November 2018.
- Новейшие истребители Су-57 прошли боевые испытания в Сирии – Шойгу Archived 4 March 2018 at the Wayback Machine Zvezda, 1 March 2018.
- Su-57 fifth-generation fighter jets successfully tested in Syria Archived 2 March 2018 at the Wayback Machine TASS, 1 March 2018.
- "Alert 5 » Su-57 launched cruise missile while deployed to Syria – Military Aviation News". alert5.com. Archived from the original on 27 May 2018. Retrieved 26 May 2018.
- "Russian Military Unveils Video Footage of New Su-57 Stealth Fighter in Syria". Retrieved 30 November 2018.
- "Russia's 5th-generation fighter jets make 10 flights in Syria" (in Russian). TASS. Archived from the original on 30 November 2018. Retrieved 30 November 2018.
- "Russia 'Tests' Su-57 Stealth Fighter Jet's Onboard Systems, Weapons in Syria". Defense world. Archived from the original on 30 November 2018.
- "Su-57 fighter jet once again tested in Syria — Russian General Staff". TASS. 18 December 2019. Retrieved 20 December 2019.
- Butowski (2021), p. 65
- "Источник в ОПК сообщил о применении Россией Су-57 в спецоперации на Украине". TASS. 20 May 2022.
- "Many Russian warplanes fire missiles from inside Russian airspace". The Times of India. 12 March 2022.
- "IAF to induct 214 variants of fighter aircraft". The Times of India. Archived from the original on 31 January 2019. Retrieved 31 January 2019.
- Mathews, Neelam. "Indian Air Force Chief Outlines Fighter Jet Plans". Aviation International News. Archived from the original on 31 January 2019. Retrieved 31 January 2019.
- "..:: India Strategic ::. Air Force: IAF decides on 144 Fifth Generation Fighters". indiastrategic.in. Archived from the original on 28 September 2013. Retrieved 31 January 2019.
- Gady, Franz-Stefan (23 April 2018). "India Pulls out of Joint Stealth Fighter Project With Russia". The Diplomat. Archived from the original on 26 April 2018.
- "В Индии назвали условия закупки Су-57". РИА Новости (in Russian). 19 July 2019. Retrieved 11 December 2019.
- "Sukhoi Su-57 not on IAF radar, Air Chief Marshal Birender Singh Dhanoa says decision after fighter joins Russian Air Force". zeenews.india.com. Retrieved 11 December 2019.
- "Россия и Индия обсуждают создание истребителя пятого поколения". RIA Novosti. 19 August 2018. Retrieved 6 September 2020.
- "India still with fifth-generation fighter aircraft project: Russian defence aviation major". zeenews.india.com. 20 August 2018. Retrieved 6 September 2020.
- Siddiqui, Huma (5 October 2019). "Make in India: IAF will focus on the indigenous AMCA for its fighter fleet, says Air Chief RKS Bhadauria". The Financial Express. Retrieved 22 March 2020.
- "Russia's fifth-generation fighter to be cheaper than foreign analogues" Archived 3 September 2014 at the Wayback Machine.
- Tae-hoon, Lee. "Russia seeks to sell stealth jets to Korea" Archived 29 September 2011 at the Wayback Machine. Korea Times, 20 July 2011.
- "South Korea confirms Sukhoi T-50's surprise entry into FX fighter contest". janes.com. 22 July 2011. Archived from the original on 16 September 2012. Retrieved 13 May 2022.
- Lee, Tae-Hoon. "Russia pulls out of Korea fighter project" Archived 31 January 2012 at the Wayback Machine. The Korean Times, 29 January 2012. Retrieved 30 January 2012.
- "Russia to Offer Brazil Stake in Future Advanced Fighter Project". RIA Novosti. 14 October 2013. Archived from the original on 14 October 2013. Retrieved 14 October 2013.
- "Russia proposes to Brazil a joint agreement to produce Sukhoi T-50 PAK-FA". 14 October 2013. Archived from the original on 3 November 2013. Retrieved 3 November 2013.
- Shukla, Ajai (30 October 2014). "Brazil chooses Gripen over Rafale". Business Standard India. Retrieved 19 July 2021.
- "F-X2: Brazils Saab Contract for Gripens a Done Deal". Defense Industry Daily. Retrieved 19 July 2021.
- Reim2021-06-03T22:05:00+01:00, Garrett. "Brazilian air force to nearly double Saab Gripen order, cut KC-390 order in half: reports". FlightGlobal. Retrieved 19 July 2021.
- "Russia 'ready to cooperate' to sell Turkey Su-57 fighter jets". Hürriyet Daily News. 3 May 2019. Archived from the original on 4 May 2019. Retrieved 6 May 2019.
- "Russia's Su-57 jet lands in Turkey for Technofest". TASS. 14 September 2019. Retrieved 15 September 2019.
- GDC (7 February 2020). "Turkey rejects Russian Su-57 fighter jet". Global Defense Corp. Retrieved 14 July 2021.
- "L'Algérie serait le premier client export pour le Su-57 et le Su-34". Mena defense. 27 December 2019. Retrieved 31 December 2019.
- "Algeria to get 14 Su-57 fighters from Russia". African Aerospace.
- "Algeria buys 14 stealth fighters from Russia, report says". 24 November 2020.
- "Sukhoi Forecasted 600 Su-57 Sale During Design Phase of the Aircraft". Global Defense Corp. 25 June 2021. Retrieved 20 July 2021.
- "Algeria to Receive Su-57 in 2028". Global Defense Corp. 8 December 2020. Retrieved 20 July 2021.
- "Vietnam To Become 1st Country To Get Russian SU-57 5th Generation Fighter Jets". EurAsian times. 8 January 2019. Retrieved 8 February 2021.
- "Su-57 may not be built with quality workmanship, says Vietnam's MoD". Global Defense Corp. 9 July 2021. Retrieved 14 July 2021.
- Trevithick, Joseph. "Russia Says UAE Could Help Build Su-57s As Gulf Nation Puts F-35 Ambitions On Hold". The War Zone. Retrieved 2 December 2019.
- "Russian Efforts to Sale Su-57E to India and UAE Failed Again". Global Defense Co. 10 March 2021. Retrieved 19 July 2021.
- "Iraqi military leadership interested in russian Su-57 next generation fighter". Military watch magazine. Retrieved 19 July 2021.
- "Su-57E Perspective multirole fighter". Rosoboronexport. Retrieved 22 March 2021.
- "LIMA 2019: Russia set to clear Sukhoi Su-57 for export". 28 March 2019. Archived from the original on 29 March 2019. Retrieved 14 April 2019.
- "MAKS 2019: Russia unveils export variant of Su-57". janes.com. 30 August 2019. Retrieved 31 August 2019.
- "Production of upgraded version of Su-57 fighter is to start in 2025 — source". TASS.
- Diplomat, Franz-Stefan Gady, The. "India and Russia Fail to Resolve Dispute Over Fifth Generation Fighter Jet". The Diplomat. Archived from the original on 27 March 2019. Retrieved 31 January 2019.
- Bogdanov, Konstantin. "Russia’s Changing Aircraft Export Strategy" Archived 23 July 2014 at the Wayback Machine. RIA Novosti, 9 July 2012.
- Mathews, Neelam. "India’s Version of Sukhoi T-50 Delayed by Two Years." Archived 7 July 2014 at the Wayback Machine AIN, 25 May 2012.
- "Russia, India Describe Next-Gen Fighter Plans" Archived 12 October 2014 at the Wayback Machine.
- "It's No Surprise India Finally Ditched Its Stealth Fighter Program With Russia". The War Zone. 23 April 2018. Archived from the original on 26 April 2018.
- "Легкий истребитель 5-го поколения будет создан на базе технологий тяжелого перспективного истребителя (in Russian)". Archived 18 September 2011 at the Wayback Machine arms-tass.su. Retrieved: 26 January 2011.
- "IHS Jane's: в России разработали новый ядерный суперавианосец". RIA Novosti. 20 May 2015. Archived from the original on 22 September 2017. Retrieved 21 September 2017.
- "Владимир Поспелов: десятый "Борей" сдадут до 2030 года". 17 May 2021.
- Druzhinin, Alexei (28 September 2009). "Russian Navy to get fifth generation carrier fighter after 2020". RIA Novosti. Archived from the original on 8 October 2010. Retrieved 26 January 2011.
- "Russia's Su-57 plane tests onboard systems for 6th-generation fighter jet – source". TASS. 16 July 2018. Archived from the original on 17 July 2018. Retrieved 21 February 2018.
- "Источник: бортовые системы истребителя шестого поколения испытывают на Су-57". TASS. 16 July 2018. Archived from the original on 28 July 2018. Retrieved 23 July 2018.
- "Russia may upgrade advanced Su-57 aircraft to 6th-generation fighter jet". TASS. Retrieved 27 August 2019.
- "Источник: системы БПЛА "Охотник" испытывают на Су-57". TASS. 29 January 2019. Archived from the original on 31 January 2019. Retrieved 21 February 2019.
- "Источник: для управления беспилотниками "Охотник" разработают двухместный Су-57".
- "Истребитель Су-57 потерпел первую аварию". Vedomosti (in Russian). 24 December 2019. Retrieved 24 December 2019.
- "Первый среди лучших: чем уникален переданный в ВКС РФ истребитель пятого поколения Су-57". tvzvezda.ru. 29 January 2021.
- "Russian Aerospace Forces received two more Su-57 in late 2021". janes.com. 24 January 2022.
- "Southern Military District to get the first serial Su-57 multirole fighters". 13 June 2019.
- "Истребитель Су-57 разбился в Хабаровском крае". Izvestia (in Russian). 24 December 2019. Retrieved 24 December 2019.
- "Власти Хабаровского края подтвердили информацию о падении Т-50" (in Russian). REN TV. 24 December 2019. Retrieved 24 December 2019.
- "В Хабаровском крае разбился истребитель Су-57" (in Russian). RIA Novosti. 24 December 2019. Retrieved 24 December 2019.
- "Источник: упавший в Хабаровском крае Су-57 самопроизвольно вошел в спираль" (in Russian). TASS. 25 December 2019. Retrieved 25 December 2019.
- "Sukhoi T-50 Shows Flight-Control Innovations". Aviation Week & Space Technology. Archived from the original on 27 March 2014. Retrieved 14 November 2014.
- Butowski (2021), p. 75
- Gordon & Komissarov 2021, Chapter 7
- "Су-35С или Су-57: что важнее для ВКС России? – Армейский вестник". Army-news.ru. Archived from the original on 19 November 2018. Retrieved 12 December 2018.
- "Су-57 вооружат сверхдальней гиперзвуковой ракетой Р-37М". Interfax.ru. 26 September 2018. Archived from the original on 18 December 2018. Retrieved 12 December 2018.
- "Новые боеприпасы значительно расширят боевой потенциал Су-57". Российская газета. Archived from the original on 30 June 2018. Retrieved 12 December 2018.
- "Су-57 теперь летает с новейшим оружием". vesti.ru. Archived from the original on 30 June 2018. Retrieved 12 December 2018.
- "Истребитель Су-57 на испытаниях превзошел лучшие американские аналоги". Российская газета. Archived from the original on 29 December 2018. Retrieved 12 December 2018.
- "T-50 / Project 701 / PAK FA." Archived 27 January 2006 at the Wayback Machine GlobalSecurity.org. Retrieved: 26 January 2011.
- Butowski, Piotr (2021). Su-57 Felon. Stamford, UK: Key Books. ISBN 978-1-913870-44-7.
- Gordon, Yefim; Komissarov, Dmitry (2021). Famous Russian Aircraft: Sukhoi Su-57. Cheshire, United Kingdom: Crecy Publishing. ISBN 9781910809938.
- Lake, Jon. "Sukhoi T-50 - Russia's Raptor?" Combat Aircraft, Vol. 11, No.4, April 2010.
- Sweetman, Bill. "Sukhoi T-50 Shows Flight-Control Innovations". Aviation Week & Space Technology, 19 August 2013. New York City, New York, US: Penton Media, Inc.