Saturn AL-31


AL-31 / 41F
Saturn AL-31 FN turbofan engine
Type Turbofan
National origin USSR/Russia
Manufacturer NPO Saturn, UMPO, NPC Saljut
Major applications Sukhoi Su-27
Sukhoi Su-30
Sukhoi Su-35
Shenyang J-11
Chengdu J-10
Chengdu J-20
Sukhoi S-70B Okhotnik-B (UCAV)
Developed from Lyulka/Saturn AL-21F-3A
Developed into Saturn AL-41

The Saturn AL-31 is a family of military turbofan engines, developed by the Lyulka, now NPO Saturn, in the Soviet Union/Russia, originally for the Sukhoi Su-27 air superiority fighter. It produces a thrust of 28,000 lbf (123 kN) with afterburning in the AL-31F, 31,000 lbf (137 kN) in the AL-31FM (AL-35F) and 33,000 lbf (145 kN) in the AL-37FU variants. Currently it powers all Su-27 derivatives and the Chengdu J-10 multirole jet fighter which has been developed under a Russian license by China. The AL-31 is a Heavily Upgraded Version of the Lyulka AL-21


Name Description Builder Year Thrust Thrust vectoring Aircraft Status
AL-31F[1][2][3][4] The basic engine developed to power the Su-27 fighter Salyut, UMPO 1981 27,600 lbf (122.6 kN) No Sukhoi Su-27, Shenyang J-11, Sukhoi Su-30MKK, Sukhoi Su-30 (Salyut) In service/production
AL-31F3 Improved variant for the naval version Su-33 Saturn Lyul'ka 28,200 lbf (125.57 kN) No Sukhoi Su-33 In service/production
AL-31FP Improved variant for the Indian Su-30MKI with thrust vectoring Salyut, HAL 2000 27,600 lbf (122.6 kN) Yes Sukhoi Su-30 MKI, Sukhoi Su-30MKM In service/production
AL-31FN[5] Improved variant for the Chengdu J-10 Salyut 2002 28,000 lbf (124.5 kN) No Chengdu J-10 In service/production
AL-31FN Series 3[6] Improved variant for the Chengdu J-10B Salyut 2013 30,200 lbf (134.3 kN) No Chengdu J-10 In service/production[7]
AL-31F M1[8] Improved version for the Russian Air Force Salyut 2007 30,300 lbf (135 kN) Yes Sukhoi Su-27SM, Sukhoi Su-30, Sukhoi Su-34 In service/production
AL-31F M2[9] Improved version for the Su-34 and Chengdu J-20 Salyut 2012 32,600 lbf (145 kN) No Sukhoi Su-34, Chengdu J-20 In service/production
AL-37FU Advanced derivative for the Su-37 UMPO 32,600 lbf (145 kN) Yes Sukhoi Su-37 Experimental derivative for the Su-37
AL-41F-1S (117S)[10] Advanced derivative for the Su-35 UMPO 2010 31,900 lbf (142 kN) Yes Sukhoi Su-35 In service/production
AL-41F1 (117) Advanced derivative for the Sukhoi Su-57 UMPO 2010 33,000 lbf (147 kN) Yes Sukhoi Su-57 prototype In service/production

The AL-31FP and AL-37FU variants have thrust vectoring. The former is used in the Su-30MKI export version of the Su-30 for India & Sukhoi Su-30MKM for Malaysia . The AL-31FP can deflect its nozzle to a maximum of ±15° at a rate of 30°/sec. The vectoring nozzle is used primarily in the pitch plane. The AL-31FP is built in India by HAL at the Koraput facility under a deep technology transfer agreement.

It can tolerate severely distorted air flow from the intake. In the twin-engine Su-27, left and right engines are interchangeable. The Mean Time Between Overhaul (MTBO) for the AL-31F is 1000 hours with a full-life of 3000 hours.

Salyut supplies AL-31 variants to fighters operated by the People's Republic of China. The J-10 uses the AL-31FN while the J-20 uses the AL-31FM2 as an interim engine until the domestic WS-15 is ready.[11]

According to Saturn's Victor Mihailovich Chepkin, chief designer of the 117 and 117S engines, the Chinese WS-10 was developed with the aid of the AL-31's maintenance technical documentation.,[12] this was recently confirmed by AVIC [13]

AL-41F1S (117S)

Intended to power the Su-35BM, the izdeliye 117S, or AL-41F1S, is derived from the AL-41F1 of the Su-57, with the key difference being the separate engine control system of the AL-41F1S.[14] The engine produces 86.3 kN (19,400 lbf) of thrust dry, 137.3 kN (30,900 lbf) in afterburner, and 142.2 kN (32,000 lbf) in an emergency.[15] The AL-41F1S fan diameter of 932 mm (36.7 in) is 3% greater than the AL-31's 905 mm (35.6 in). This engine has an assigned life of 4,000 hours and an MTBO of 1,000 hours.[16] The first flight of this engine was completed in an Su-35BM on 20 February 2008.[17] On 9 August 2010, Ufa-based company UMPO started supplying 117S engines (AL-41F1S) intended for Su-35S fighters.[18]

AL-41F1 (117)

Intended to power the fifth-generation Sukhoi Su-57 fighter, the izdeliye 117, or AL-41F1, is a highly improved AL-31F derivative, with some application of technology from the Saturn AL-41F. Its development began in 2004 and has increased fan diameter, new high- and low-pressure turbines, provisions for thrust-vectoring nozzles similar to the AL-31FP, and a digital control system (FADEC) integrated into the aircraft's flight controls. According to Sukhoi director Mikhail Pogosyan, the AL-41F1 is a new fifth-generation engine built specifically for the Su-57. Though the specifics remain classified, the engine's thrust was increased by 24.5 kN (5,500 lbf) over the AL-31 while the engine weight growth was reduced by 150 kg (330 lb). The AL-41F1 produces 147 kN (33,000 lbf) of thrust in afterburner and has a dry weight of approximately 1,600 kg (3,500 lb) and thrust-to-weight ratio of 9.3:1.[19][20] Like the AL-31F, the AL-41F1 has 4 low-pressure compressor (fan) and 9 high-pressure compressor stages.[21] Mikhail Pogosyan further mentioned that the AL-41F1 meets the Russian Air Force requirements and will be installed in production Su-57 fighter which will be supplied to the Russian Air Force and prospective foreign clients.[20]

Izdeliye 30 (Item 30)

The AL-41F1 (117S) is an interim engine meant for prototype and initial production batches of the Su-57. The definitive second stage for the aircraft is designated izdeliye 30 and will eventually replace the AL-41F1 after the mid-2020. The izdeliye 30 engine will have increased thrust and fuel efficiency as well as improved reliability and lower costs. Bench testing of the new engine will start in 2014 according to the general designer-director of the NPO Saturn Eugeny Marchuk.[22] Test flights began in 2017 being still underway in 2020. At the time it was expected that serial deliveries of Su-57 fifth-generation fighters fitted out with the new engines could begin in 2022.[23]

Specifications (AL-31F)

Data from Gordon,[24] Rosoboronexport,[25] United Engine Corporation[26]

General characteristics



Specifications AL-41F-1S (117S)

Data from Rosobornexport[27]

General characteristics

  • Type: Two-shaft afterburning turbofan
  • Length: 194.6 in (494.2 cm)
  • Diameter: 36.7 in (93.2 cm) inlet
  • Dry weight: 3,536 lb (1,604 kg)


  • Compressor: Axial, 4 stage fan, 9 stage compressor
  • Combustors: Annular
  • Turbine: 2 single stage turbines


  • Maximum thrust:
    • 19,400 lbf (86.3 kN) dry
    • 30,900 lbf (137.3 kN) with afterburner
    • 32,000 lbf (142.2 kN) emergency thrust
  • Turbine inlet temperature: 2,681 °F; 1,472 °C (1,745 K),
  • Fuel consumption:
    • 15,020 lb/h (6,813 kg/h) dry
    • 55,050 lb/h (24,969 kg/h) with afterburner
  • Specific fuel consumption:
    • 0.790 lb/lbf/h (22.37 g/kN/s) dry
    • 1.819 lb/lbf/h (51.53 g/kN/s) with afterburner
  • Thrust-to-weight ratio: 5.49 (dry), 8.75 with afterburner, 9.04 with emergency thrust

See also

Comparable engines

Related lists


  1. ^ "UMPO page on AL-31F". Retrieved 3 April 2018.
  2. ^ Salyut page on AL-31F
  3. ^ [1]
  4. ^ "AL-31F". Rosoboronexport.
  6. ^ "JOINT-STOCK COMPANY "GAS-TURBINE ENGINEERING RESEARCH AND PRODUCTION CENTER «SALUT" - NEWS - NEWS - FSUE "Gas-Turbine Engineering RPC "Salut" has successfully completed the first phase of engine longevity and performance bench tests in view of future deliveries of a new version of AL-31FN Series 3". Retrieved 3 April 2018.
  7. ^ "JOINT-STOCK COMPANY "GAS-TURBINE ENGINEERING RESEARCH AND PRODUCTION CENTER «SALUT" - NEWS - NEWS - The FSUE "GTE-RPC "Salut"-produced AL-31FN series-3 engine receives code letter "O1"". Retrieved 3 April 2018.
  8. ^ "АО "НПЦ газотурбостроения «САЛЮТ" - Продукция - АВИАЦИОННЫЕ ДВИГАТЕЛИ - АЛ-31Ф серии 42 (М1)". Retrieved 3 April 2018.
  9. ^ "JOINT-STOCK COMPANY "GAS-TURBINE ENGINEERING RESEARCH AND PRODUCTION CENTER «SALUT" - NEWS - NEWS - AL-31F M2 engine contemplated by OKB Sukhogo (Sukhoi Design Bureau)". Retrieved 3 April 2018.
  10. ^ "UMPO press release". Retrieved 3 April 2018.
  11. ^ Rupprecht, Andreas (1 November 2016). "China's new J-20 "Mighty Dragon" stealth fighter officially unveiled and ready to enter active service".
  12. ^ Коробковwrote, Егор; 14:23:00, 2011-08-17 14:23:00 Егор Коробков korobok12 2011-08-17. "О положении дел в Российском авиамоторостроении. Год 2008". Retrieved 3 April 2018.CS1 maint: numeric names: authors list (link)
  13. ^ F_200788. "AVIC report: China's Taihang engine widely deployed in military - People's Daily Online". Retrieved 3 April 2018.
  14. ^ АВДЕЕВ, Юрий (24 March 2010). "«СУ»ДАРЬ РАСПРАВЛЯЕТ КРЫЛЬЯ". Красная звезда. Archived from the original on 23 April 2010.
  15. ^ Hillebrand, Niels. "MILAVIA Aircraft - Sukhoi Su-35 (Su-27BM) "4++ Generation Flanker"". Retrieved 3 April 2018.
  16. ^ "NPO Saturn finishes endurance tests for S-117 Engine meant for Su-35". Archived from the original on 28 March 2008. Retrieved 3 April 2018.
  17. ^ "Новый истребитель Су-35 полностью выполнил программу первого полета". 20 February 2008. Retrieved 3 April 2018.
  18. ^ "Новости - Приволжский федеральный округ -". Retrieved 3 April 2018.
  19. ^ Butowski, Piotr (October 2019). "The Final Flanker; Russian Fifth-Gen". Air International. London: Key Publishing. Retrieved 12 April 2020.
  20. ^ a b PAK-FA is flying with new engine already installed Archived July 27, 2011, at the Wayback Machine
  21. ^ Butowski, Piotr. "Is Russia’s fifth-generation PAK FA fighter programme still on track?". Air International, June 2015, pp. 76–81. Stamford, UK: Key Publishing.
  22. ^ "НПО "Сатурн" создает двигатель поколения 5+ - Еженедельник "Военно-промышленный курьер"". Retrieved 3 April 2018.
  23. ^ "Russia to roll out Su-57 fifth-generation fighter with 2nd-stage engine in 2022". TASS. 2020-12-20.
  24. ^ Gordon, Yefim (2006). Sukhoi Su-27. Specialty Press. p. 91. ISBN 1-5800-7196-1.
  25. ^ "AL-31F". Rosobonexport.
  26. ^ "AL-31F". United Engine Corporation.
  27. ^ "AL-41F-1S". Rosobornexport.

External links

  • Russian Military Analysis - AL-31 F aircraft turbofan engine
  • AL-31F on (cs,en)
  • AL-41F1A (117S) on (cs,en)