The General Electric GE90 is a family of high-bypass turbofan aircraft engines built by GE Aerospace for the Boeing 777, with thrust ratings from 81,000 to 115,000 pounds-force (360 to 510 kilonewtons). It entered service with British Airways in November 1995. It is one of three options for the 777-200, -200ER, and -300 versions, and the exclusive engine of the -200LR, -300ER, and 777F. It was the largest jet engine,[3] until being surpassed in January 2020 by its successor, the 110,000 lbf (490 kN) GE9X, which has a larger fan diameter by 6 inches (15 cm). However, the GE90-115B, the most recent variant of the GE90, is rated for a higher thrust (115,000 lbs) than the GE9X.

GE90
GE90-115B
Type Turbofan
National origin United States
Manufacturer GE Aerospace
First run March 1993[1]
Major applications Boeing 777
Produced 1993-present
Number built 2,800 by July 2020[2]
Developed into General Electric GEnx
Engine Alliance GP7000
General Electric GE9X

Background

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In the early 1980s, GE began to develop an unducted fan (UDF) engine, which was thought to be a more fuel-efficient option to propel short-haul airliners, a compelling proposition after the 1979 oil crisis. NASA gave GE a grant in February 1984 to continue its research, eventually building the experimental GE36. One of the major innovations for the engine were its carbon fiber composite fan blades, which were both lighter and stronger than traditional materials.[4] However, the UDF was less reliable than the turbofans of the era, lower fuel costs made the cost of developing the engine less attractive, and the company was worried the GE36 would cannibalize sales of the highly successful CFM56 engine it had co-developed with Snecma of France.[4]

Development

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The GE90 engine was launched in 1990 to provide a large turbofan engine for the Boeing 777, a wide-body, long-range, twin-engine jet airliner.[5] GE Aviation teamed with Snecma (France, 24%), IHI (Japan) and Avio (Italy) for the program.[6] The GE90 would face stiff competition as Pratt & Whitney and Rolls-Royce would also offer engines for the 777, the PW4000 and Trent 800, respectively.

The major innovation of the GE90 was that it used 22 carbon fiber composite fan blades, technology first developed for the GE36. These blades provided double the strength at one-third the weight of traditional titanium fan blades. The 22 fan blades were a significant reduction from the 38 blades used in GE's prior large turbofan, the CF6, despite the 30-inch (760 mm) greater diameter of the GE90. Having fewer fan blades reduces the engine weight and improves aerodynamic efficiency.

With the stiff competition to equip the first generation 777 models (777-200, 777-200ER, no GE90 orders for the 777-300), GE tried to branch out and use the GE90 for other aircraft. Then-CEO Brian H. Rowe went so far as to offer to pay for the development of the GE90 for the Airbus A330, but Airbus rebuffed the plan, instead choosing to focus on the four-engine A340 for the long-haul market.[7]

In the late 1990s, Boeing began developing the second-generation 777 long-range variants (777-200LR, 777-300ER, 777F). For these aircraft a more powerful engine in the thrust class of 100,000 lbf (440 kN) was required, leading to talks between Boeing and engine manufacturers. General Electric offered to develop the GE90-115B engine,[8] while Rolls-Royce proposed developing the Trent 8104 engine.[9] In 1999, Boeing announced an agreement with General Electric, beating out rival proposals.[8] Under the deal with General Electric, Boeing agreed to only offer GE90 engines on new 777 versions.[8] The GE90-115B had its first run at the GE facility in Peebles, Ohio in November 2001.[10]

Design

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The GE90-115B diameter is 128 in (325 cm) while the 777 fuselage is 244 in (620 cm)

The GE90's 10-stage high-pressure compressor developed a then-industry record pressure ratio of 23:1 and is driven by a 2-stage, air-cooled, HP turbine. A 3-stage low-pressure compressor, situated directly behind the fan, supercharges the core. The fan/LPC is driven by a 6-stage low-pressure turbine.

The higher-thrust variants, GE90-110B1 and -115B, have a different architecture from that of the earlier GE90 versions. General Electric incorporated an advanced larger diameter fan made from composite materials which enhanced thrust at low flight speeds. However, GE also needed to increase core power to improve net thrust at high flight speeds. Consequently, GE elected to increase core capacity, which they achieved by removing one stage from the rear of the HP compressor and adding an additional stage to the LP compressor, which more than compensated for the reduction in HP compressor pressure ratio, resulting in a net increase in core mass flow .[11] The higher-thrust GE90 variants are the first production engines to feature swept rotor blades. The nacelle has a maximum diameter of 166 in (4,200 mm).[12] Each of the 22 fan blades on the GE90-115B have a length of 4 feet (1.2 meters) and a mass of less than 50 pounds (23 kilograms).[13]

Operational history

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As one of the three available engines for the all-new Boeing 777 large twinjet airliner, the GE90 was an all-new $2 billion design in contrast to the offerings from Pratt & Whitney and Rolls-Royce which were modifications of existing engines.[14]

The first General Electric-powered Boeing 777 was delivered to British Airways on November 12, 1995.[15] The aircraft, with two GE90-77Bs, entered service five days later. Initial service was affected by gearbox bearing wear concerns, which caused the airline to temporarily withdraw its 777 fleet from transatlantic service in 1997. British Airways' aircraft returned to full service later that year.[16]

Problems with GE90 development and testing caused delays in Federal Aviation Administration certification. British Airways soon replaced the GE90 with the Rolls-Royce Trent 800 on their 777s. No 777-300s were ordered with the GE90, and ending up this combination was never certified by the FAA. In addition the GE90's increased thrust was not yet required by airlines and it was also the heaviest engine of the three available choices, making it the least popular option on these first generation 777s (777-200, 777-200ER, 777-300, also known collective as the 777 Classics) while the Rolls-Royce engine was the most popular. [14][17]

 
A GE90-115B engine

For Boeing's second-generation 777 long-range versions (later named 777-200LR, 777-300ER, and 777F), greater thrust was needed to meet the aircraft requirements. General Electric and Pratt & Whitney insisted on a winner-take-all contract due to the $500 million investment in engine modifications needed to meet the requirements. GE received sole engine supplier status for the higher-thrust engine variants for the 777-200LR, -300ER, and 777F.[14][17] The improved version entered service with Air France in May 2004.[18]

The higher thrust GE90-110B1 and -115B engines, in combination with the second-generation 777 variants -200LR and -300ER, were primary reasons for 777 sales being greater than those of the rival A330/340 series.[19] Using two engines produces a typical operating cost advantage of around 8–9% for the -300ER over the A340-600.[20] The 777-300ER was also seen as a 747-400 replacement amid rising fuel prices given its 20% fuel burn advantage.[21]

Until passed by its derivative, the GE9X, the GE90 series held the title of the largest engines in aviation history. The fan diameter of the original series being 123 in (310 cm), and the largest variant GE90-115B has a fan diameter of 128 in (330 cm). As a result, the GE90 engine can only be air-freighted using an outsize cargo aircraft such as the Antonov An-124, which restricts shipping options if, due to an emergency diversion, a 777 were stranded needing an engine change. If the fan and fan case are removed the engine may be shipped using a 747 Freighter.[22]

The -94B for the -200ER was retrofitted with some of the first FAA-approved 3D-printed components.[23]

In 2011, its list price was US$27.5 million, and it had an in-flight shutdown rate (IFSD) of one per million engine flight-hours.[3] Until November 2015, it accumulated more than 8 million cycles and 50 million flight hours in 20 years.[24] In July 2020, the fleet of 2,800 engines surpassed 100 million hours, powering over 1,200 aircraft for 70 operators with a dispatch reliability rate of 99.97%.[2] A complete overhaul costs more than $12 million.[25]

Records

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GE90 without cowling
 
The higher-thrust GE90-115B mounted on N747GE, GE's Boeing 747 test aircraft.

The GE90-115B provided enough thrust to fly N747GE, GE's Boeing 747-100 flying testbed with the other three engines at idle, an attribute demonstrated during a flight test.[26][27]

According to the Guinness Book of Records, at 127,900 lbf (569 kN), the engine held the record for the highest thrust achieved by an aircraft engine (the maximum thrust for the engine in service is its rated thrust 115,300 lbf (513 kN)). This thrust record was reached inadvertently as part of a one-hour, triple-red-line engine stress test using a GE90-115B development engine at GE's outdoor test complex near Peebles, Ohio. It eclipsed the engine's previous Guinness world record of 122,965 lbf (546.98 kN).[28] On November 10, 2017, its successor, the GE9X, reached a higher record thrust of 134,300 lbf (597 kN) in Peebles.[29]

The initial GE90 fan shaft design loads were greatly increased for operational torque and the fan blade-off condition. To accommodate the increase in fan-shaft torsional and bending stresses, a steel alloy, GE1014, not previously used in aircraft engines was required. A significantly longer fan shaft spline-coupling was required and maintaining the required high machining accuracy was challenging.[30][31]

In October 2003, a Boeing 777-300ER broke the ETOPS record by being able to fly five and a half hours (330 minutes) with one engine shut down.[32] The aircraft, with GE90-115B engines, flew from Seattle to Taiwan as part of the ETOPS certification program.

On November 10, 2005, the GE90 entered the Guinness World Records for a second time. The GE90-110B1 powered a 777-200LR during the world's longest flight by a commercial airliner, though there were no fare-paying passengers on the flight, only journalists and invited guests. The 777-200LR flew 13,423 mi (21,602 km) in 22 hours, 22 minutes, flying from Hong Kong to London "the long way": over the Pacific, over the continental U.S., then over the Atlantic to London.[33]

Incidents

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On August 11, 2004, a GE90-85B powering a Boeing 777-200ER on British Airways flight 2024 suffered an engine failure on takeoff from George Bush Intercontinental Airport, Houston. The pilots noticed a noise and vibration on takeoff but continued the rotation. At 1500 ft AGL they noticed smoke and haze in the cockpit and cabin crew advised cabin was filling with smoke. They returned to the airport for an immediate emergency landing. Findings were a stage 2 turbine blade had separated at its shank damaging the trailing blades causing the vibration. The debris was contained in the engine casing.[34]

On May 28, 2012, an Air Canada 777-300ER taking off from Toronto en route to Tokyo suffered failure of a GE90-115B at 1,500 feet (460 m) and returned safely. Engine debris was found on the ground.[35][36]

On September 8, 2015, a GE90-85B powering a Boeing 777-236ER on British Airways Flight 2276 suffered an uncontained failure during take-off roll at Las Vegas McCarran Airport, leading to a fire. NTSB and FAA investigations were begun to determine the cause; initial findings were reported in September 2015.[37][38]

On June 27, 2016, a GE90-115B powering a Boeing 777-300ER, on Singapore Airlines Flight 368, received an engine oil warning during flight and returned to Singapore Changi Airport. On landing the malfunctioning right engine caught fire, leading to fire damage to the engine and the wing.[39]

Transfer gearbox failures

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The FAA issued an Airworthiness Directive (AD) on May 16, 2013, and sent it to owners and operators of General Electric GE90-110B1 and GE90-115B turbofan engines. This emergency AD was prompted by reports of two failures of transfer gearbox assemblies (TGBs) which resulted in in-flight shutdowns (IFSDs). Investigation revealed that the failures were caused by TGB radial gear cracking and separation. This through the combined effect of manufacturing process and operating stresses.[40] Further inspections found two additional radial gears with cracks. This condition, if not corrected, could result in additional IFSDs of one or more engines, loss of thrust control, and damage to the airplane. The Airworthiness Directive requires compliance by taking remedial measures within five days of receipt of the AD. All affected modules have been replaced.[41]

Specifications

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A GE90-94B (Boeing 777-200ER), straight fan blades
A GE90-110B1 (Boeing 777-200LR), curved fan blades
GE90 Type Certificate Data Sheet[42]
Variant -76B/-77B/-85B/-90B/-94B -110B1/-113B/-115B
Type Dual rotor, axial flow, high bypass turbofan
Compressor 1 fan, 3-stage LP, 10-stage HP 1 fan, 4-stage LP, 9-stage HP[43]
Turbine 2-stage HP, 6-stage LP
Length[a] 286.9 in (7.29 m) 286.67 in (7.281 m)
Max. width 152.4 in (3.87 m) 148.38 in (3.769 m)
Max. height 155.6 in (3.95 m) 154.56 in (3.926 m)
Fan diameter[44] 123 in (3.1 m) 128 in (3.3 m)
Weight[b] 17,400 lb (7,893 kg) 19,316 lb (8,762 kg)
Takeoff thrust 81,070–97,300 lbf (360.6–432.8 kN) 110,760–115,540 lbf (492.7–513.9 kN)[c]
LP rotor speed 2,261.5 rpm 2,355 rpm
HP rotor speed 9,332 rpm
Bypass ratio[6] 8.4 - 9 9
Pressure ratio[43] 40:1 42:1
Thrust-to-weight ratio 5.59 5.98
Takeoff TSFC 0.278 lb/lbf/h (7.9 g/kN/s)[45]
Cruise TSFC 0.545 lb/lbf/h (15.4 g/kN/s) (-76B)[46] (-85B)[47]
or 0.520 lb/lbf/h (14.7 g/kN/s) (-85B)
[46][48]

Derivatives

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GEnx

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The GEnx engine, that has been developed for the Boeing 787 Dreamliner and 747-8, is derived from a smaller core variant of the GE90, also featuring a fan with swept rotor blades.

GP7000

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GE Aviation set up a cooperative venture with Pratt & Whitney, named Engine Alliance, under which the companies have developed an engine for the Airbus A380, named GP7000, based on an 0.72 flow scale of the GE90-110B/115B core.

GE9X

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In February 2012, GE announced studies on a 10% more efficient derivative, dubbed the GE9X, to power the new Boeing 777-8X/9X aircraft.

LM9000

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The LM9000 is an aeroderivative gas turbine available in two options; the LM9000 without water augmentation outputting 66 MW (89,000 hp) at a 42.4% efficiency before cogeneration, and the LM9000 with water augmentation outputting 75 MW (101,000 hp) at a 42.7% efficiency before cogeneration.[49] The engine's 33:1 pressure ratio comes from a 4-stage low pressure compressor followed by a 9 stage high pressure compressor, driven by a 2 stage high pressure turbine and a 1-stage low pressure turbine, powering a 4-stage free turbine.[50]

See also

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Related development

Comparable engines

Related lists

References

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  1. ^ Fan spinner to nozzle centerbody
  2. ^ Dry, Includes basic engine, basic engine accessories, and optional equipment
  3. ^ world record set at 127,900 lbf (569 kN) in testing 827 feet above sea level[28]

Notes

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  1. ^ Brian J. Cantwell (February 2, 2010). "The GE90 - An Introduction" (PDF). Stanford University. Archived from the original (PDF) on September 30, 2017. Retrieved February 2, 2016.
  2. ^ a b "GE90 engine surpasses 100 million hours" (Press release). GE Aviation. July 24, 2020. Archived from the original on July 28, 2020. Retrieved July 28, 2020.
  3. ^ a b "Record Year For The World's Largest, Most Powerful Jet Engine" (Press release). GE Aviation. January 19, 2012. Archived from the original on January 1, 2019. Retrieved January 1, 2019.
  4. ^ a b Sweetman, Bill (September 2005). "The Short, Happy Life of the Prop-fan". Smithsonian. Archived from the original on August 14, 2017. Retrieved June 16, 2017.
  5. ^ "First Year in Service for GE90 a Huge Success" (Press release). GE Aviation. November 18, 1996. Archived from the original on December 1, 2017. Retrieved November 28, 2017.
  6. ^ a b "commercial aircraft engines -GE90" (PDF). Snecma. Safran. Archived (PDF) from the original on November 7, 2016. Retrieved November 7, 2016.
  7. ^ Scott Hamilton (December 14, 2017). "Top Airbus officials scoffed at Leahy's 50% market share goal". Leeham. Archived from the original on November 29, 2018. Retrieved December 14, 2017.
  8. ^ a b c "A question of choice". Flight International. January 3, 2000. Archived from the original on April 14, 2009. Retrieved March 29, 2009.
  9. ^ "Aero-Engines – Rolls-Royce Trent". Jane's Transport Business News. February 13, 2001. Archived from the original on March 25, 2008. Retrieved March 21, 2009.
  10. ^ "Full GE90 tests get under way". Flight Global. Archived from the original on February 12, 2022. Retrieved May 26, 2020.
  11. ^ "The GE90:ge aviations greatest comeback story". GE Aviation. December 2, 2019. Archived from the original on February 6, 2020. Retrieved February 12, 2020.
  12. ^ Dominic Gates (January 4, 2019). "The biggest jet engines ever seen are set to roar on Boeing's 777X". The Seattle Times. Archived from the original on January 4, 2019. Retrieved January 4, 2019.
  13. ^ The Museum of Modern Art (2007). "Jet engine fan blade (model GE90-115B)". In Roberts, Rebecca (ed.). MoMA highlights since 1980: 250 works from the Museum of Modern Art, New York. The Museum of Modern Art. p. 175. ISBN 978-0-87070-713-1. OCLC 191091211. Retrieved October 18, 2022.
  14. ^ a b c "GE90 secures exclusive position on 777X". Flight Global. July 14, 1999. Archived from the original on August 18, 2016. Retrieved August 1, 2016.
  15. ^ Eden, Paul, ed. (2008). Civil Aircraft Today: The World's Most Successful Commercial Aircraft. London: Amber Books Ltd. p. 115. ISBN 978-1-84509-324-2.
  16. ^ Norris, Guy; Mark Wagner (1999). Modern Boeing Jetliners. Minneapolis, Minnesota: Zenith Imprint. pp. 143–144. ISBN 0-7603-0717-2.
  17. ^ a b "How Ge Locked Up That Boeing Order". Bloomberg. August 9, 1999. Archived from the original on September 12, 2017. Retrieved March 7, 2017.
  18. ^ "GE90-115B: GE's Best-Ever New Jet Engine Entry Into Airline Service" (Press release). GE Aviation. July 17, 2006. Archived from the original on December 26, 2019. Retrieved December 26, 2019.
  19. ^ "Airbus A350 XWB puts pressure on Boeing 777". flightglobal. November 26, 2007. Archived from the original on March 8, 2016. Retrieved June 16, 2017.
  20. ^ Ben Kingsley-Jones; Guy Norris (November 29, 2005). "Enhanced A340 to take on 777". Flight International. Archived from the original on March 7, 2016. Retrieved June 16, 2017.
  21. ^ Jens Flottau (November 14, 2011). "Airbus Bids Adieu to A340, Postpones A350 Delivery". Aviation Week & Space Technology. Archived from the original on May 14, 2016. Retrieved August 12, 2014.
  22. ^ "GE strives to identify Air France engine fault". Flight International. January 3, 2006. Archived from the original on June 13, 2017. Retrieved November 7, 2016.
  23. ^ "The FAA Cleared The First 3D Printed Part To Fly In A Commercial Jet Engine From GE". GE reports. GE Aviation. April 14, 2015. Archived from the original on June 29, 2017. Retrieved April 22, 2015.
  24. ^ "Etihad Airways signs engine agreements with GE for Boeing 777 Freighters" (Press release). GE Aviation. November 10, 2015. Archived from the original on August 7, 2016. Retrieved July 21, 2016.
  25. ^ Scott Hamilton (November 8, 2021). "Pontifications: As customers wait for 787s, some rethink 777-300ERs". Leeham News. Archived from the original on November 10, 2021. Retrieved November 10, 2021.
  26. ^ General Electric Biggest Jet Engine for B-777. History Channel. 2008. Event occurs at 3:00–3:10 min. Archived from the original on December 12, 2021. Retrieved July 11, 2013.
  27. ^ "GE90-115B certification: a look at the flight tests". Le Webmag. Safran. August 8, 2003. Archived from the original on November 1, 2006.
  28. ^ a b "GE90 Sets New World Record For Thrust; Engine Completes FAR 33 Certification Tests" (Press release). GE Aviation. February 5, 2003. Archived from the original on June 14, 2011. Retrieved April 14, 2011.
  29. ^ "GE9X Breaks GUINNESS WORLD RECORDS™ Title for Thrust" (Press release). GE Aviation. July 12, 2019.[permanent dead link]
  30. ^ Development of GE90-115B Turbofan Engine,Horibe et al., IHI Engineering Review,Vol.37 No.February 1, 2004,p.6
  31. ^ "Impressive Progress of GE90-115B Engine Continues" (Press release). GE Aviation. July 24, 2000. Archived from the original on March 6, 2009. Retrieved December 19, 2008.
  32. ^ "Boeing 777-300ER Performs 330-Minute ETOPS Flight" (Press release). Boeing. October 15, 2003. Archived from the original on November 4, 2016. Retrieved November 3, 2016.
  33. ^ "Flight-distance record awaits as big 777 heads to London". Seattle Post-Intelligencer. November 8, 2005. Archived from the original on October 21, 2016. Retrieved November 7, 2016.
  34. ^ url= https://www.ntsb.gov/_layouts/ntsb.aviation/brief2.aspx?ev_id=20041015X01640&ntsbno=DCA04IA066&akey=1 Archived April 28, 2018, at the Wayback Machine
  35. ^ "Maintenance inspection a factor in 2012 Air Canada engine failure during take-off from Lester B. Pearson International Airport". Transportation Safety Board of Canada. December 13, 2013. Archived from the original on October 19, 2015. Retrieved September 11, 2015.
  36. ^ Edmiston, Jake (May 29, 2012). "Air Canada plane debris struck cars after engine failure, safety board confirms". National Post. Archived from the original on February 12, 2022. Retrieved November 7, 2016.
  37. ^ Charles Alcock (September 8, 2015). "Engine Failure Causes Fire on British Airways Boeing 777". Aviation International News. Archived from the original on May 28, 2020. Retrieved September 9, 2015.
  38. ^ "NTSB Issues Update on the British Airways Engine Fire at Las Vegas". NTSB. September 8, 2015. Archived from the original on September 12, 2015. Retrieved August 8, 2015.
  39. ^ "Fire damage apparent on SIA 777 wing". Flight Global. June 27, 2016. Archived from the original on September 20, 2019. Retrieved November 7, 2016.
  40. ^ M Scarfo, Jean-Pierre. "National Transportation Safety Board Aviation Incident Final Report" (PDF). Skybrary. National Transportation Safety Board. Retrieved November 19, 2022.
  41. ^ "Emergency airworthiness directive (AD) 2013-10-52" (PDF). FAA. May 16, 2013. sent to owners and operators of General Electric Company (GE) GE90-110B1 and GE90-115B turbofan engines. Archived from the original (PDF) on November 7, 2016. Retrieved November 7, 2016.
  42. ^ "Type Certificate Data Sheet E00049EN" (PDF). FAA. June 23, 2016. Archived from the original (PDF) on February 9, 2020. Retrieved November 7, 2016.
  43. ^ a b "GE90 Commercial Aircraft Engine". GE Aviation. Archived from the original on March 29, 2016. Retrieved March 28, 2016.
  44. ^ "GE90-115B Fan Completing Blade Testing; On Schedule For First Engine To Test" (Press release). GE Aviation. June 17, 2001. Archived from the original on January 1, 2019. Retrieved January 1, 2019.
  45. ^ "Engine Directory Part 1 - Turbofans". Flight International. November 14, 2000. Archived from the original on February 16, 2019. Retrieved February 16, 2019.
  46. ^ a b Kumar, Parth; Khalid, Adeel (2017). "Blended Wing Body Propulsion System Design". International Journal of Aviation, Aeronautics, and Aerospace. 4 (4): 28. doi:10.15394/ijaaa.2017.1187. ISSN 2374-6793. Archived from the original on June 3, 2021. Retrieved July 10, 2021.
  47. ^ Lloyd R. Jenkinson & al. (July 30, 1999). "Civil Jet Aircraft Design: Engine Data File". Elsevier/Butterworth-Heinemann. Archived from the original on May 6, 2021. Retrieved February 16, 2019.
  48. ^ Sahai, Abhishek Kumar (June 24, 2016). Consideration of Aircraft Noise Annoyance during Conceptual Aircraft Design (PDF) (Thesis). Table 5.2: Comparison of key Gasturb simulated and reference values for the GE90-85B engine. Archived (PDF) from the original on June 2, 2021. Retrieved May 30, 2021.
  49. ^ "LM9000". General Electric. Archived from the original on July 2, 2018. Retrieved July 2, 2018.
  50. ^ "LM9000 - The new prime mover for oil and gas" (PDF). General Electric. 2017. Archived (PDF) from the original on July 2, 2018. Retrieved June 30, 2017.
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