This is a good article. Follow the link for more information.

Sukhoi Su-37

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Su-37
Sukhoi Su-37 at Farnborough 1996 airshow.jpg
Role Air superiority fighter technology demonstrator
Manufacturer Komsomolsk-on-Amur Aircraft Production Association
Design group Sukhoi Design Bureau
First flight 2 April 1996
Status Development ceased, aircraft crashed
Number built 1 (conversion from Su-27M)
Developed from Sukhoi Su-35 (Su-27M)

The Sukhoi Su-37 (Russian: Сухой Су-37; NATO reporting name: Flanker-F) is a single-seat twin-engine aircraft designed by the Sukhoi Design Bureau that served as a technology demonstrator. It allowed for the need to enhance pilot control of the Su-27M (later renamed Su-35), which was a further development of the Su-27. The sole aircraft had originally been built as the eleventh Su-27M (T10M-11) by the Komsomolsk-on-Amur Aircraft Production Association before having its thrust-vectoring nozzles installed. In addition, it was modified with updated flight- and weapons-control systems. The aircraft made its maiden flight in April 1996. Throughout the flight-test program, the Su-37 demonstrated its supermanoeuvrability at air shows, performing manoeuvres such as a 360-degree somersault. The aircraft crashed in December 2002 due to structural failure. The Su-37 did not enter production; despite a report in 1998 which claimed that Sukhoi had built a second Su-37 using the twelfth Su-27M airframe,[1] T10M-11 remained the sole prototype. Sukhoi had instead applied the aircraft's systems to the design bureau's other fighter designs.

Design and development[edit]

The Sukhoi Design Bureau started research on thrust vectoring as early as 1983,[2] when the Soviet government tasked the bureau with the separate development of the Su-27M, which was an upgrade of the Su-27.[3] At the insistence of General Director Mikhail Simonov, who had been the chief designer of the Su-27, Sukhoi and the Siberian Aeronautical Research Institute studied axisymmetrical vectoring nozzles. This was in contrast to the prevailing focus on two-dimensional nozzles in the Western press. Lyulka (later Lyulka-Saturn) also began studies of thrust-vectoring engines in 1985.[4] By the late 1980s, Sukhoi were evaluating their research using its flying test beds.[5]

During test flights of the Su-27Ms, which began in 1988, engineers discovered that pilots failed to maintain active control of the aircraft at high angles of attack due to the ineffectiveness of flight control surfaces at low speeds. Engineers therefore installed thrust-vectoring engines to the eleventh Su-27 (factory code T10M-11), which had been built by the Komsomolsk-on-Amur Aircraft Production Association in the country's Far East and was being used as a radar test bed.[6] Following the airframe's completion in early 1995, the aircraft was delivered to the design bureau's experimental plant near Moscow, where engineers started installing the nozzles on the aircraft.[7][N 1] Although Sukhoi had intended the Lyulka-Saturn AL-37FU to power the aircraft, the engine had not yet been flight-cleared. The aircraft was temporarily fitted with the less-powerful AL-31FP engine, which was essentially an AL-31F engine that had the AL-100 vectoring nozzles of the AL-37FU.[7] The aircraft was rolled out in May.[9] Two months later, the temporary engines were replaced with AL-37FUs; its nozzles could only deflect 15 degrees up or down in the pitch axis, together or differentially.[10]

Apart from the addition of thrust-vectoring nozzles, the Su-37 did not outwardly differ much from the canard-equipped Su-27M. Instead, engineers had focused on the aircraft's avionics. Unlike previous Su-27Ms, the Su-37 had a digital (as opposed to analogue) fly-by-wire flight control system, which was directly linked to the thrust-vectoring control system.[11] Together with the aircraft's overall high thrust-to-weight ratio and the engine's full authority digital engine control feature, the integrated propulsion and flight control systems added manoeuvrability at high angles of attack and low speeds.[12] The aircraft's weapons-control system had also been improved, as it included an N011M Bars (literally "Panther") pulse-Doppler phased-array radar that provided the aircraft with simultaneous air-to-air and air-to-ground capability. The radar was capable of tracking twenty aerial targets and directing missiles toward eight of them simultaneously; in comparison, the Su-27M's baseline N011 could only track fifteen aerial targets and engage six of them simultaneously.[13][14] The aircraft retained from the Su-27M the N012 self-defence radar located in the rearward-projecting tail boom.[5]

Considerable improvement had also been made to the cockpit layout. In addition to the head-up display, the Su-37 had four Sextant Avionique multi-function colour liquid crystal displays arranged in a "T" configuration; they had better backlight protection than the Su-27M's monochrome cathode ray tube displays. The displays presented to the pilot information about navigation, systems status, and weapons selection. The pilot sat on an ejection seat that was reclined to 30 degrees to improve g-force tolerance.[5][15]

Painted in a disruptive sand and brown scheme, the aircraft was given the code 711 Blue, later changed to 711 White.[15] Following ground checks at the Gromov Flight Research Institute, the aircraft made its maiden flight on 2 April 1996 from Zhukovsky Airfield outside Moscow, piloted by Yevgeni Frolov. The nozzles were fixed during the first five flights.[14][N 2] Due to the lack of funding from the Russian Air Force, Sukhoi was compelled to finance the project with its own funds; according to Simonov, the company channelled revenue from the exports of the Su-27s to China and Vietnam towards the project.[5][16] The aircraft was publicly unveiled at Zhukovsky later in the year, and was redesignated Su-37.[14]

Operational history[edit]

During the subsequent flight-test programme, the Su-37's supermanoeuvrability as a result of thrust-vectoring controls became apparent. According to Simonov, such a feature would allow pilots to develop new combat manoeuvres and tactics, greatly enhancing its effectiveness in dogfights.[17] Among the new manoeuvres was the Super Cobra, which was a variation of the Pugachev's Cobra and was demonstrated during the aircraft's international debut at the Farnborough Airshow in September 1996. Piloted by Frolov, the aircraft pitched up 180 degrees and maintained the tail-first position momentarily, which would theoretically allow the aircraft to fire a missile at a combat opponent.[14] The Super Cobra evolved into the kulbit (somersault), in which the Su-37 performed a 360-degree loop with an extremely tight turning radius the length of the aircraft.[18] According to test pilot Anatoly Kvochur, thrust vectoring would have given the aircraft a considerable advantage in close-in dogfights.[19] Nonetheless, critics have questioned the practical benefits of such manoeuvres; although they would allow an early missile lock-on, it would come at the expense of a rapid loss of kinetic energy, which would leave the aircraft vulnerable when pilots missed their first shot.[20]

The aircraft was demonstrated at the Paris Air Show in 1997. Although it was only able to perform on the last day of the show, the organisers recognised the Su-37 as the standout performer at the event.[21] The aircraft thereafter participated in the MAKS air show in Moscow, the International Defence Exhibition in Dubai, and the FIDAE air show in Santiago, Chile, as authorities sought to export the aircraft.[22] With the expiration of the engines' service lives, the aircraft later had the AL-37FUs replaced with standard production AL-31F engines that lacked movable nozzles. The loss of thrust vectoring was somewhat compensated for by an update to the fly-by-wire flight control system. The aircraft's foreign avionics were also replaced with indigenous designs. It resumed test flights in October 2000.[23]

The flight-test programme was ended on 19 December 2002, when the aircraft's port horizontal tail broke off during a high-g manoeuvre, leading to its crash at Shatura, near Moscow. The structural failure was caused by repeated exceeding of the aircraft's design load during six years of testing.[24] The pilot Yuri Vashuk ejected safely.[25][26] Despite the entry of the Su-37 into Brazilian and South Korean fighter tenders, the aircraft failed to gain any foreign customers. India in the mid-1990s funded the development of what would result in the Su-30MKI, which is a two-seat fighter design that incorporated the canards, N011M radar and thrust-vectoring technology that were present and evaluated on the Su-37.[27] In addition, through tests of the Su-27M and the Su-37, engineers had determined that thrust vectoring could compensate for the loss of manoeuvrability brought about by the removal of canards, the design of which imposed a weight penalty on the airframe.[28] The modernized Su-35, without canards,[29] made its first flight in February 2008.[30]

Specifications (Su-37)[edit]

Data from Gordon,[31] Novichkov[11]

General characteristics

Performance

Armament

  • Guns: 1× 30 mm GSh-30-1 internal cannon with 150 rounds
  • Hardpoints: 12 hardpoints, consisting of 2 wingtip rails, and 10 wing and fuselage stations with a capacity of 8,000 kg (17,630 lb) of ordnance.

Avionics

See also[edit]

Related development

Aircraft of comparable role, configuration and era

Related lists

References[edit]

Footnotes[edit]

  1. ^ According to Flight International, engineers started installing the nozzles to the aircraft in late 1994.[8]
  2. ^ Quote: "The aircraft, Su-27 number 711, had five flights in April, apparently with the axisymmetric nozzles in a fixed configuration."[16]

Citations[edit]

  1. ^ Gethin 1998, p. 32.
  2. ^ Gordon 2007, p. 144.
  3. ^ Andrews 2003, p. 39.
  4. ^ Gordon 2007, pp. 146–147.
  5. ^ a b c d Novichkov 1996, p. 55.
  6. ^ Gordon 2007, pp. 142, 151.
  7. ^ a b Gordon 2007, p. 151.
  8. ^ Barrie 1994, p. 16.
  9. ^ Aviation Week & Space Technology 1995, p. 35.
  10. ^ Novichkov 1996, pp. 52, 55.
  11. ^ a b Novichkov 1996, p. 52.
  12. ^ Gordon 2007, pp. 151, 154.
  13. ^ Butowski, Piotr (1 November 1999). "Dominance by design: the reign of Russia's 'Flankers' – PART ONE". Jane's Intelligence Review. Coulsdon, UK. 11 (11). ISSN 1350-6226.
  14. ^ a b c d Gordon 2007, p. 158.
  15. ^ a b Gordon 2007, p. 154.
  16. ^ a b Velovich May 1996, p. 16.
  17. ^ Novichkov 1996, p. 50.
  18. ^ Velovich September 1996, p. 41.
  19. ^ Butowski, Piotr (10 July 1996). "Su-37 dogfights will be '10 times as effective'". Jane's Defence Weekly. Horley, UK. ISSN 0265-3818.
  20. ^ Flight International 1996, p 3: "If the pilot does not kill the opposition with his first shot, then his own aircraft's lack of energy will means [sic] he could present an attractive target."
  21. ^ Petrov, Ivan (25 June 1997). Су-37 — истребитель года. Kommersant (in Russian). Archived from the original on 10 October 2017. Retrieved 10 October 2017.
  22. ^ Gordon 2007, pp. 160, 164.
  23. ^ Andrews 2003, p. 58.
  24. ^ Gordon 2007, p. 172.
  25. ^ "Sukhoi demonstrator crashes during testing". Flightglobal. 31 December 2002. Archived from the original on 9 November 2012. Retrieved 25 August 2013.
  26. ^ В Подмосковье разбился истребитель Су-35. Kommersant (in Russian). 19 December 2002. Archived from the original on 5 January 2016. Retrieved 16 October 2017.
  27. ^ Andrews 2003, p. 47.
  28. ^ Barrie 2003, p. 39: "While the canard layout brought advantages in terms of improved maneuverability, it also added structural weight to the airframe. A conventional airframe coupled with thrust vector control, the source said, could now provide the same capability."
  29. ^ Butowski 2004, p. 39: "The problem was solved in a similar way: removal of the canards from the airframe structure. The aircraft maneuverability will not be affected since modern control systems are much more effective than those used previously. The Su-35BM [sic] will be equipped with the control system similar to the quadruple digital fly-by-wire SDU-427 system from the Su-47 Berkut experimental fighter. Additionally, the Su-35BM may also be fitted with thrust vectoring."
  30. ^ Lantratov, Constantine (20 February 2008). Взлетела новая "сушка". Kommersant (in Russian). Retrieved 12 November 2017.
  31. ^ Gordon 2007, p. 453.

Bibliography[edit]

  • "Su-35 Has New Nozzles". Aviation Week & Space Technology. New York: McGraw-Hill. 143 (4): 35. 24 July 1995. ISSN 0005-2175.
  • "Deft Manoeuvres". Flight International (commentary). London, UK: Reed Business Publishing. 150 (4540): 3. 11–17 September 1996. ISSN 0015-3710. Archived from the original on 10 October 2017. Retrieved 5 November 2017.
  • Andrews, Thomas (Spring 2003). "Su-27/30 family: 'Flanker' in the 21st Century". International Air Power Review. 8. Norwalk, Connecticut: AIRtime Publishing. ISBN 978-1-880588-54-3.
  • Barrie, Douglas (16–22 November 1994). "New Su-35 nozzles fitted". Flight International. London, UK: Reed Business Publishing. 146 (4447): 16. ISSN 0015-3710. Archived from the original on 9 October 2017. Retrieved 5 November 2017.
  • ——— (1 September 2003). "Singular Demands". Aviation Week & Space Technology. New York: McGraw-Hill. 159 (9): 39. ISSN 0005-2175.
  • Butowski, Piotr (Summer 2004). "Halfway to PAK FA". Interavia Business & Technology. Geneva: Aerospace Media Publishing (676): 38–41. ISSN 1423-3215.
  • Gethin, Howard (9–15 September 1998). "Sukhoi flies latest Su-37 demonstrator". Flight International. London: Reed Business Information. 154 (4642): 32. ISSN 0015-3710. Archived from the original on 8 November 2012. Retrieved 26 October 2013.
  • Gordon, Yefim (2007). Sukhoi Su-27. Famous Russian Aircraft. Hinckley, UK: Midlands Publishing. ISBN 978-1-85780-247-4.
  • Novichkov, Nicolay (26 August 1996). "Sukhoi Set to Exploit Thrust Vector Control". Aviation Week & Space Technology. New York: McGraw-Hill. 145 (9): 50–52, 55. ISSN 0005-2175.
  • Velovich, Alexander (8–14 May 1996). "Thrust-vectoring Su-35 flies". Flight International. London, UK: Reed Business Publishing. 149 (4522): 16. ISSN 0015-3710. Archived from the original on 12 September 2017. Retrieved 5 November 2017.
  • ——— (18–24 September 1996). "Slow slow, quick quick, slow". Flight International. London, UK: Reed Business Publishing. 150 (4541): 41. ISSN 0015-3710. Archived from the original on 10 October 2017. Retrieved 5 November 2017.

External links[edit]