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137-684: The General Electric GE9X is a high-bypass turbofan developed by GE Aerospace exclusively for the Boeing 777X . It first ran on the ground in April 2016 and first flew on March 13, 2018; it powered the 777-9's maiden flight in early 2020. It received its Federal Aviation Administration (FAA) type certificate on September 25, 2020. Derived from the General Electric GE90 with a larger fan, advanced materials like ceramic matrix composites (CMCs), and higher bypass and compression ratios, it

274-434: A carbon-fiber-reinforced polymer (CFRP) wing with a wingspan of 213 or 225 ft; 2,560 or 2,700 in (65 or 68.6 m) with blended winglets , or up to 233 ft 5 in (71.1 m) with raked wingtip would have provided for a 10% larger wing area. The aircraft would have fallen into ICAO aerodrome code F like the 747-8 and A380 but with 22 ft 6 in (6.9 m) folding wingtips would stay within

411-492: A crosswind when raised, alerting the crew when they are not correctly positioned while the mechanism and controls will be further inspected. Those ten special conditions were published on May 18, 2018, covering worst-case scenarios . Transported by sea from Subaru in Nagoya to Everett, the center wing-box is similar in size to the legacy 777 but is more reinforced and heavier, with more titanium . The internal cabin width

548-527: A 10:1 bypass ratio, a 60:1 overall pressure ratio, and 27:1 HP compressor ratio for a 10% fuel burn reduction. In March 2013, Boeing selected the GE9X with a 132 in (335 cm) fan. It is the largest fan made by GE. In the rest of 2013, thrust was bumped to 102,000 and 105,000 lbf (450 and 470 kN) to support the MTOW growing from 769,413 to 775,000 lb (349,000 to 351,534 kg) and increasing

685-460: A 120 ft (37 m) autoclave, and a robot to wind fiber for the wings. The first 777X was planned to be built on the ex-787 "surge" line. The -9 firm-configuration was reached in August 2015 and assembly of the initial aircraft was to begin in 2017 for a December 2019 introduction advanced from the previously scheduled 2020. With a current 777 production rate of 100 per year, 380 on order at

822-580: A 367,000 sq ft (34,100 m ) composites facility in St. Louis to be completed in 2016, to build 777X parts with six autoclaves for the wing and empennage parts, starting in 2017. The 787 'surge' line at the Everett factory would be converted into a 777X early production line by the end of 2015. Boeing built a 1,300,000 sq ft (120,000 m ) building adjacent to the Everett factory, with

959-684: A 777-9 with auxiliary fuel tanks and reduced seating capacity. However, Qantas subsequently preferred the Airbus A350-1000 for this project. The -8 would also fill the niche market for an aircraft capable of flying with a full payload from hubs in the Gulf states to the West Coast of the United States . It could, however, be cancelled if customers find the -9 acceptable for these routes. In August 2023, Boeing announced an increase in

1096-507: A carbon fiber composite fan case, first developed for the GEnx, to further reduce weight. The high pressure (HP) compressor is up to 2% more efficient. As the 129.5 in (329 cm) GE90 fan left little room to improve the bypass ratio, GE looked for additional efficiency by upping the overall pressure ratio from 40 to 60, focusing on boosting the high-pressure core's ratio from 19:1 to 27:1 by using 11 compressor stages instead of 9 or 10, and

1233-434: A corresponding increase in pressure and temperature in the exhaust duct which in turn cause a higher gas speed from the propelling nozzle (and higher KE and wasted fuel). Although the engine would use less fuel to produce a pound of thrust, more fuel is wasted in the faster propelling jet. In other words, the independence of thermal and propulsive efficiencies, as exists with the piston engine/propeller combination which preceded

1370-449: A delivery planned in summer 2020 to Lufthansa. The roll-out of the prototype occurred on March 13, 2019, in a low-key employees-only event overshadowed by the crash of an Ethiopian Airlines 737 MAX 8 on March 10. The GE9X engines installed on the 777X prototype were first run on May 29. However, a compressor anomaly occurred with another engine during pre-delivery tests, and the maiden flight previously planned for no earlier than June 26

1507-663: A different issue with the GE9X paused testing of the 777X. The GE9X increases fuel efficiency by 10% over the GE90. Its 61:1 overall pressure ratio should help provide a 5% lower thrust specific fuel consumption (TSFC) than the XWB-97 with maintenance costs comparable to the GE90-115B. The initial thrust of 105,000 lbf (470 kN) will be followed by 102,000 and 93,000 lbf (450 and 410 kN) derated variants. GE invested more than $ 2 billion for its development. Its nacelle

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1644-419: A discordant nature known as "buzz saw" noise. All modern turbofan engines have acoustic liners in the nacelle to damp their noise. They extend as much as possible to cover the largest surface area. The acoustic performance of the engine can be experimentally evaluated by means of ground tests or in dedicated experimental test rigs. In the aerospace industry, chevrons are the "saw-tooth" patterns on

1781-410: A fixed total applied fuel:air ratio, the total fuel flow for a given fan airflow will be the same, regardless of the dry specific thrust of the engine. However, a high specific thrust turbofan will, by definition, have a higher nozzle pressure ratio, resulting in a higher afterburning net thrust and, therefore, a lower afterburning specific fuel consumption (SFC). However, high specific thrust engines have

1918-565: A fuel burn of more than 10% lower than the GE90-115B and 15% lower than its Trent 800 powering the 777; the RB3025 concept has a composite fan, a core derived from the Trent 1000 , and advanced HP materials. Pratt & Whitney responded with the 100,000 lbf (440 kN) thrust PW1000G geared turbofan architecture. GE Aviation proposed the GE9X with a 128 in (325 cm) diameter fan,

2055-426: A high dry SFC. The situation is reversed for a medium specific thrust afterburning turbofan: i.e., poor afterburning SFC/good dry SFC. The former engine is suitable for a combat aircraft which must remain in afterburning combat for a fairly long period, but has to fight only fairly close to the airfield (e.g. cross border skirmishes). The latter engine is better for an aircraft that has to fly some distance, or loiter for

2192-416: A higher nozzle pressure ratio than the turbojet, but with a lower exhaust temperature to retain net thrust. Since the temperature rise across the whole engine (intake to nozzle) would be lower, the (dry power) fuel flow would also be reduced, resulting in a better specific fuel consumption (SFC). Some low-bypass ratio military turbofans (e.g. F404 , JT8D ) have variable inlet guide vanes to direct air onto

2329-426: A jig for robotic drilling . Boeing launched the 777-9 production on October 23 with the wing spar drilling; its maiden flight was scheduled in the first quarter of 2019, one year before its introduction, perhaps with Emirates. On November 7, 90% of the engineering drawings were released, with the airframe before the systems: 99% of the wing and 98% of the fuselage drawings are released. The detailed design phase

2466-444: A lack of "design maturity". In April 2022, after an "updated assessment of the time required to meet certification requirements", Boeing again delayed 777X deliveries, this time to 2025. In November 2022, it was revealed that the GE9X engine on one of the four test 777-9s had suffered a technical issue on October 6. Boeing subsequently paused the test program while GE investigated the issue. In May 2024, launch customer Lufthansa

2603-590: A long time, before going into combat. However, the pilot can afford to stay in afterburning only for a short period, before aircraft fuel reserves become dangerously low. The first production afterburning turbofan engine was the Pratt & Whitney TF30 , which initially powered the F-111 Aardvark and F-14 Tomcat . Low-bypass military turbofans include the Pratt & Whitney F119 , the Eurojet EJ200 ,

2740-403: A pure-jet of the same thrust, and jet noise is no longer the predominant source. Turbofan engine noise propagates both upstream via the inlet and downstream via the primary nozzle and the by-pass duct. Other noise sources are the fan, compressor and turbine. Modern commercial aircraft employ high-bypass-ratio (HBPR) engines with separate flow, non-mixing, short-duct exhaust systems. Their noise

2877-675: A range of 8,745  nmi (16,196 km; 10,064 mi) while the 777-9 has seating for 426 passengers and a range of over 7,285 nmi (13,492 km; 8,383 mi). The 777X program was proposed in the early 2010s with assembly at the Boeing Everett Factory and the wings built at a new adjacent building. As of September 2024 , there are 503 total orders for the 777X passenger and freighter versions from thirteen identified customers and unnamed buyer(s). The 777-9 first flew on January 25, 2020. Deliveries have been delayed multiple times; as of October 2024, Boeing expects

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3014-465: A routine A Check on the 747 testbed CF6 engines discovered fan-case corrosion and high pressure turbine airfoils on allowable limits. It first flew on March 13 with the previous design of the VSV lever arm. In early May, the first flight test phase of two was completed after 18 flights and 110 hours of run time; the GE9X high-altitude envelope was explored and its cruise performance evaluated. The second phase

3151-424: A second quarter first flight. By late 2019, it should be joined in the flight program by the other four 777-9 prototypes which were undergoing assembly. The first flight-test aircraft was built 20% faster than the static airframe. At the end of November, the electric systems were powered on and the rollout was expected for February 2019. First deliveries are planned for May 2020 while the first production wing spar

3288-477: A special demonstration lab is not as quick as planned. The first 777-9 fuselage assembly started in March 2018. In May 2018, Qatar Airways head Akbar Al Baker thought development was a couple of months late but expects Boeing to catch up, provided no certification issues arise. To avoid disrupting current 777 assembly, a temporary low-rate assembly line was set up for up to 38 airframes before transitioning to

3425-569: A static thrust of 4,320 lb (1,960 kg), and had a bypass ratio of 6:1. The General Electric TF39 became the first production model, designed to power the Lockheed C-5 Galaxy military transport aircraft. The civil General Electric CF6 engine used a derived design. Other high-bypass turbofans are the Pratt & Whitney JT9D , the three-shaft Rolls-Royce RB211 and the CFM International CFM56 ; also

3562-523: A third-generation, twin-annular pre-swirl (TAPS) combustor instead of the previous dual annular combustor. Able to endure hotter temperatures, ceramic matrix composites (CMC) are used in two combustor liners, two nozzles, and the shroud up from the CFM International LEAP stage 2 turbine shroud . CMCs are not used for the first-stage turbine blades, which have to endure extreme heat and centrifugal forces. These are improvements planned for

3699-473: A turbofan engine is the ratio between the mass flow rate of the bypass stream to the mass flow rate entering the core. A bypass ratio of 6, for example, means that 6 times more air passes through the bypass duct than the amount that passes through the combustion chamber. Turbofan engines are usually described in terms of BPR, which together with overall pressure ratio, turbine inlet temperature and fan pressure ratio are important design parameters. In addition BPR

3836-421: A turbojet engine uses all of the engine's output to produce thrust in the form of a hot high-velocity exhaust gas jet, a turbofan's cool low-velocity bypass air yields between 30% and 70% of the total thrust produced by a turbofan system. The thrust ( F N ) generated by a turbofan depends on the effective exhaust velocity of the total exhaust, as with any jet engine, but because two exhaust jets are present

3973-496: A turbojet even though an extra turbine, a gearbox and a propeller are added to the turbojet's low-loss propelling nozzle. The turbofan has additional losses from its greater number of compressor stages/blades, fan and bypass duct. Froude, or propulsive, efficiency can be defined as: η f = 2 1 + V j V a {\displaystyle \eta _{f}={\frac {2}{1+{\frac {V_{j}}{V_{a}}}}}} where: While

4110-704: A turbojet which accelerates a smaller amount more quickly, which is a less efficient way to generate the same thrust (see the efficiency section below). The ratio of the mass-flow of air bypassing the engine core compared to the mass-flow of air passing through the core is referred to as the bypass ratio . Engines with more jet thrust relative to fan thrust are known as low-bypass turbofans , those that have considerably more fan thrust than jet thrust are known as high-bypass . Most commercial aviation jet engines in use are high-bypass, and most modern fighter engines are low-bypass. Afterburners are used on low-bypass turbofans on combat aircraft. The bypass ratio (BPR) of

4247-438: Is 184 in (4,700 mm) wide. Most of the efficiency increase comes from the better propulsion efficiency of the higher-bypass-ratio fan. The bypass ratio is planned for 10:1. The fan is housed in 134 in (340 cm) diameter case. The GE9X has 16 blades , whereas the similarly sized GE90 has 22 and the smaller GEnx has 18. Having fewer fan blades reduces the engine weight, improves aerodynamic efficiency, and allows

General Electric GE9X - Misplaced Pages Continue

4384-507: Is best suited to high supersonic speeds. If it is all transferred to a separate big mass of air with low kinetic energy, the aircraft is best suited to zero speed (hovering). For speeds in between, the gas power is shared between a separate airstream and the gas turbine's own nozzle flow in a proportion which gives the aircraft performance required. The trade off between mass flow and velocity is also seen with propellers and helicopter rotors by comparing disc loading and power loading. For example,

4521-410: Is considerable potential for reducing fuel consumption for the same core cycle by increasing BPR.This is achieved because of the reduction in pounds of thrust per lb/sec of airflow (specific thrust) and the resultant reduction in lost kinetic energy in the jets (increase in propulsive efficiency). If all the gas power from a gas turbine is converted to kinetic energy in a propelling nozzle, the aircraft

4658-439: Is distributed between Charleston, Huntsville, Long Beach, Philadelphia, and St. Louis in the U.S and Moscow, Russia. Its development cost could be over $ 5 billion with at least $ 2 billion for the carbon-composite wing. On September 18, 2013, Lufthansa became its launch customer by selecting 34 Boeing 777-9X airliners, along with 25 Airbus A350-900s to replace its 22 747-400s and 48 A340-300/600s for its long-haul fleet. At

4795-430: Is due to the speed, temperature, and pressure of the exhaust jet, especially during high-thrust conditions, such as those required for takeoff. The primary source of jet noise is the turbulent mixing of shear layers in the engine's exhaust. These shear layers contain instabilities that lead to highly turbulent vortices that generate the pressure fluctuations responsible for sound. To reduce the noise associated with jet flow,

4932-400: Is equipped with automatic riveters , transfer, and painting machines. Boeing's first composite wing spars, stringers, and skin panels are formed in the $ 1 billion Composite Wing Center before assembly on a new horizontal build line. In February 2018, its wing components were ready to go through assembly as Mitsubishi Heavy Industries , the 787 composite wings manufacturer, advised Boeing on

5069-473: Is increased from the previous 777 models' 231 to 235 in (587 to 597 cm) through thinner interior cabin walls and better insulation to allow 18.0 in (46 cm) wide seats in 10-abreast economy. The 777X will feature cabin design details requiring structural changes that were originally introduced on the Boeing 787 Dreamliner : larger windows, higher ceilings, more humidity and lowered cabin altitude to 6,000 ft (1,800 m). Its flight deck

5206-508: Is installed in a 174 in (440 cm) diameter nacelle, with 1.5 ft (0.46 m) of ground clearance. The engine and nacelle weighed 40,000 lb (18 t) with its new pylon and wing strengthening, compared to 17,000 lb (7.7 t) for the CF6-80C2s and its pylon. In February 2018, the GE9X's first flight was delayed by problems discovered in the high-pressure compressor (HPC) variable stator vanes (VSV) lever arms. Also

5343-413: Is quoted for turboprop and unducted fan installations because their high propulsive efficiency gives them the overall efficiency characteristics of very high bypass turbofans. This allows them to be shown together with turbofans on plots which show trends of reducing specific fuel consumption (SFC) with increasing BPR. BPR can also be quoted for lift fan installations where the fan airflow is remote from

5480-429: Is similar to the 787 cockpit with large displays and head-up displays , controls for the folding wingtips, and touchscreens replacing cursor control devices . Windows are dimmable. For the longer 777-9, replacing the engines should improve fuel consumption by 10%, with the longer, carbon-fiber wings adding an estimated 7% improvement. As 4 to 5% of fuel savings is lost from the 12 tons heavier basic structure of

5617-420: Is sufficient core power to drive the fan. A smaller core flow/higher bypass ratio cycle can be achieved by raising the inlet temperature of the high-pressure (HP) turbine rotor. To illustrate one aspect of how a turbofan differs from a turbojet, comparisons can be made at the same airflow (to keep a common intake for example) and the same net thrust (i.e. same specific thrust). A bypass flow can be added only if

General Electric GE9X - Misplaced Pages Continue

5754-418: Is used to manufacture parts that would otherwise be impossible to make using traditional manufacturing processes. In August 2024, a first production bound engine will be delivered, with a new combustor liner design. Related development Comparable engines Related lists High-bypass turbofan The ratio of the mass-flow of air bypassing the engine core to the mass-flow of air passing through

5891-411: Is very fuel intensive. Consequently, afterburning can be used only for short portions of a mission. Unlike in the main engine, where stoichiometric temperatures in the combustor have to be reduced before they reach the turbine, an afterburner at maximum fuelling is designed to produce stoichiometric temperatures at entry to the nozzle, about 2,100 K (3,800 °R; 3,300 °F; 1,800 °C). At

6028-468: The Boeing 737 MAX groundings and the delayed first flight of the 777-9, in 2019 Boeing pushed back design and development of the 777-8 until at least 2021, for first deliveries expected in 2023 or beyond. The delays were not expected to affect Boeing's participation in Qantas' Project Sunrise , for which it has proposed a 777-8 variant. Boeing also proposed an interim solution to Qantas, assumed to comprise

6165-479: The Bristol Olympus , and Pratt & Whitney JT3C engines, increased the overall pressure ratio and thus the thermodynamic efficiency of engines. They also had poor propulsive efficiency, because pure turbojets have a high specific thrust/high velocity exhaust, which is better suited to supersonic flight. The original low-bypass turbofan engines were designed to improve propulsive efficiency by reducing

6302-702: The General Electric F110 , the Klimov RD-33 , and the Saturn AL-31 , all of which feature a mixed exhaust, afterburner and variable area propelling nozzle. To further improve fuel economy and reduce noise, almost all jet airliners and most military transport aircraft (e.g., the C-17 ) are powered by low-specific-thrust/high-bypass-ratio turbofans. These engines evolved from the high-specific-thrust/low-bypass-ratio turbofans used in such aircraft in

6439-608: The flight envelope such as low altitudes; #5 ran an endurance test with rotors deliberately unbalanced to make the engine shake at the vibration limits allowed in service, a requirement for ETOPS certification; #6 did ingestion tests later in 2018; after LP turbine over-temperature tests, #7 did a second icing test phase in Winnipeg, Manitoba ; #8 did the triple redline FAA 150 h endurance test. Eight compliance engines, plus two spares, were required for 777-9 flight testing. A second phase, of 18 flights, began on December 10 to evaluate

6576-497: The long-range , wide-body , twin-engine jetliners in the Boeing 777 family from Boeing Commercial Airplanes . The changes for 777X include General Electric GE9X engines, composite wings with folding wingtips , greater cabin width and seating capacity, and technologies from the Boeing 787 . The 777X was launched in November 2013 with two variants: the 777-8 and the 777-9. The 777-8 provides seating for 395 passengers and has

6713-412: The payload-range , with a possible 108,000 lbf (480 kN) envisioned. Some customers bemoaned the loss of engine competition, like Air Lease Corporation 's CEO Steven Udvar-Hazy who wanted a choice of engines. Airbus points out that handling more than one engine type adds millions of dollars to an airliner cost. Pratt and Whitney said: "Engines are no longer commodities...the optimization of

6850-421: The 1960s. Modern combat aircraft tend to use low-bypass ratio turbofans, and some military transport aircraft use turboprops . Low specific thrust is achieved by replacing the multi-stage fan with a single-stage unit. Unlike some military engines, modern civil turbofans lack stationary inlet guide vanes in front of the fan rotor. The fan is scaled to achieve the desired net thrust. The core (or gas generator) of

6987-462: The 2017–2018 winter at Winnipeg, Manitoba . Simulated high-altitude conditions were used to test the GE9X for ice crystal icing (core icing) which was an issue for the GEnx . This testing improved the understanding of core icing as well as the more familiar rime ice . A design change required for the GEnx was the addition of bypass doors between the booster and high-pressure compressor which open into

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7124-421: The 213 ft 4 in (65.02 m) code E like current 777s. Horizontal stabilizers also were extended. The General Electric GE90 -115B of the earlier 777-200LR and -300ER variants has a 42:1 overall pressure ratio and 23:1 HP compressor ratio. Rolls-Royce Plc proposed its RB3025 concept with a 132 in (335 cm) fan diameter, a 12:1 bypass ratio , and a 62:1 overall pressure ratio, targeting

7261-465: The 777-300ER. Its maximum takeoff weight is targeted for 775,000 lb (351.5 t) like the 777-300ER but Boeing hopes to have at least a 10,000 lb (4.5 t) margin at introduction. Boeing predicts the -8 to be 4% more fuel efficient and cost effective than the A350-1000, while the -9 would be 12% more fuel efficient and 11% more cost effective. Lufthansa, when it ordered both, stated

7398-626: The 777X does not have an equivalent of the Maneuvering Characteristics Augmentation System (MCAS) that is installed on the 737 MAX and that played a role in two crashes. The first test flight took place on January 25, 2020, at 10:09 a.m. from Paine Field in Everett, and ended in Boeing Field in Seattle after 3 hours and 52 minutes. The second 777X first flew on April 30, by which point

7535-420: The 777X first flight until January 2020. On January 25, 2020, the GE9X had its first flight on the 777X, flying for 3 hours and 52 minutes, before landing at Boeing Field. On September 28, GE announced its FAA type certificate, as eight test engines completed 8,000 cycles and 5,000 hours of running. ETOPS approval needed 3,000 ground-test cycles to be completed as a requirement for entry into service. In 2022,

7672-460: The 787 wing but with less sweep , this wing has a higher lift-to-drag ratio , aspect ratio increased from 9:1 to 10:1, area increased from 4,702 to 5,562 sq ft (436.8 to 516.7 m ), and usable fuel capacity increased from 320,863 to 350,410 lb (145,541 to 158,943 kg). To stay within the size category of the current 777 with a less than 213 ft (65 m) wingspan, it features 11 feet (3.5 m) folding wingtips with

7809-495: The Airbus A350-900 and the 777-9X will consume an average of 2.9 L/100 km per passenger. The 777-8 is a shortened derivative of the 777-9, initially specified as 229 ft (69.8 m) long, between the 209 ft 1 in (63.7 m) 777-200 and 242 ft 4 in (73.9 m) 777-300. It would seat typically 395 passengers with a range of 8,745 nmi (16,170 km; 10,050 mi). It would succeed

7946-645: The FAUB robotic system was abandoned after six years of implementation, to use human machinists more. By mid-November, a pair of flight compliant engines were installed on the first 777-9. As part of an investigation by the FAA into the fatal crashes of the Boeing 737 MAX aircraft, emails were released that showed that a problematic supplier of parts for the 737 MAX flight simulators was still being used for 777X simulators, on an even more aggressive schedule. Boeing stated that

8083-472: The November 2013 Dubai Airshow , the -8X for 350 passengers over a 9,300 nmi (17,200 km; 10,700 mi) range and the -9X, seating more than 400 over 8,200 nmi (15,200 km; 9,400 mi) were launched with 259 orders and commitments for US$ 95 billion (~$ 123 billion in 2023) at list prices. This was the largest commercial aircraft launch by dollar value with Emirates ordering 150, Qatar Airways 50, and Etihad Airways 25, in addition to

8220-481: The September 2013 Lufthansa commitment for 34 aircraft. Boeing dropped the variants' "X" suffix, while keeping the 777X program name at the 2015 Dubai Airshow. In June 2017, Lufthansa was considering delaying 777X deliveries and could limit its -9 orders to 20 and order more A350s. Due to its large order, Emirates will become the first operator instead of Lufthansa. In December 2014, Boeing began construction on

8357-464: The aerospace industry has sought to disrupt shear layer turbulence and reduce the overall noise produced. Fan noise may come from the interaction of the fan-blade wakes with the pressure field of the downstream fan-exit stator vanes. It may be minimized by adequate axial spacing between blade trailing edge and stator entrance. At high engine speeds, as at takeoff, shock waves from the supersonic fan tips, because of their unequal nature, produce noise of

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8494-422: The afterburner, raising the temperature of exhaust gases by a significant degree, resulting in a higher exhaust velocity/engine specific thrust. The variable geometry nozzle must open to a larger throat area to accommodate the extra volume and increased flow rate when the afterburner is lit. Afterburning is often designed to give a significant thrust boost for take off, transonic acceleration and combat maneuvers, but

8631-409: The afterburner. Modern turbofans have either a large single-stage fan or a smaller fan with several stages. An early configuration combined a low-pressure turbine and fan in a single rear-mounted unit. The turbofan was invented to improve the fuel consumption of the turbojet. It achieves this by pushing more air, thus increasing the mass and lowering the speed of the propelling jet compared to that of

8768-461: The aircraft nacelle. A core engine was tested in the Evendale, Ohio , altitude test cell to check blade vibrations and engines 003, 004, and 007 were assembled in 2017, and the fourth engine was used for flight testing later in the year from Victorville, California . In 2018 ten compliance engines (including two spare engines) were needed for the four 777-9 flight-test aircraft. Type certification

8905-432: The aircraft. The FAA did not announce how its review and certification of the 777X may be affected. The 777X was already a year behind schedule as service introduction was targeted for 2022, a further delay due to the certification as a derivative could risk key orders. Boeing received the first flight compliant GE9X on October 18 with a second engine due by the end of the month, for a mid-November power up. On November 13,

9042-499: The airflow path to reduce the chance of ice crystals entering the core. Design changes between FETT and second engine to test (SETT) addressed improvements required to meet efficiency goals: the minimum area in the duct between the HP turbine outlet and the LP turbine inlet was altered to set the operating line of the compressor, turbine and fan. The tip clearance at the front of the HP compressor

9179-426: The average stage loading and to maintain LP turbine efficiency. Reducing core flow also increases bypass ratio. Bypass ratios greater than 5:1 are increasingly common; the Pratt & Whitney PW1000G , which entered commercial service in 2016, attains 12.5:1. Further improvements in core thermal efficiency can be achieved by raising the overall pressure ratio of the core. Improvements in blade aerodynamics can reduce

9316-547: The core is referred to as the bypass ratio . The engine produces thrust through a combination of these two portions working together. Engines that use more jet thrust relative to fan thrust are known as low-bypass turbofans ; conversely those that have considerably more fan thrust than jet thrust are known as high-bypass . Most commercial aviation jet engines in use are of the high-bypass type, and most modern fighter engines are low-bypass. Afterburners are used on low-bypass turbofan engines with bypass and core mixing before

9453-545: The end of 2013 and no orders at the February 2014 Singapore Airshow , bridging the gap to the 777X deliveries starting from 2020 is a challenge: to stimulate orders, sales of current 777s can be paired with 777Xs and used 777s can be converted to freighters to be sold and stimulate sales. In April 2017, the initial one-piece wing spar came onto the assembly jig and was about to enter lay-up in June; first parts assembly for

9590-400: The end of 2017. The initial 777X flight-test engines were shipped in 2018 for an initial 777-9 flight in early 2019. A quarter of the certification testing was done by May 2018: icing, crosswind /inlet distortion, inlet distortion , fan and booster blade vibrations, HP turbine blade vibrations and thermal survey . As it was larger than the GE90, the GE9X could only be installed under

9727-403: The end of January, the turbine case and rear frame strut were damaged during the blade out test and relevant components were redesigned. In early May, the flight test program was completed after 320 hours run time, during which high-altitude cruise fuel burn was established. Engines were modified to a final certifiable configuration standard before the maiden flight of the 777X, delayed beyond

9864-448: The engine and doesn't flow past the engine core. Considering a constant core (i.e. fixed pressure ratio and turbine inlet temperature), core and bypass jet velocities equal and a particular flight condition (i.e. Mach number and altitude) the fuel consumption per lb of thrust (sfc) decreases with increase in BPR. At the same time gross and net thrusts increase, but by different amounts. There

10001-413: The engine and the aircraft becomes more relevant." In 2012, with the Boeing 737 MAX in development and the 787-10 launch in preparation, Boeing decided to slow 777X development to reduce the risk with introduction still forecast for 2019. On May 1, 2013, Boeing's board of directors approved selling the 353-seat 777-8LX to replace the 777-300ER from 2021, after the larger 406-seat -9X. The design work

10138-577: The engine control software and hot-and-high performance and lasted until the first quarter of 2019 before FAA certification the same year. By then water ingestion, crosswind, blade-out, hailstone , bird ingestion and block or endurance testing had been completed. Flight tests were based in Victorville, California , and ranged as far as Seattle , Colorado Springs, Colorado , Fairbanks, Alaska , and Yuma, Arizona . By January 4, 2019, eight test flights and 55 hours of run time had been completed. At

10275-465: The engine design in terms of aerodynamic performance, mechanical system behavior and secondary air system heat management. The GE9X conducted icing tests in Winter 2017. The FETT was used for ground cold weather testing in natural icing conditions such as ground fog ; minor design changes using additive manufacturing were made within one month. Icing certification and evaluation finished during

10412-533: The engine has 65 CMC components, the most of any commercial aircraft engine at the time of its introduction. The compressor is designed with 3D aerodynamics and its first five stages are blisks , combined bladed-disk. The combustor is lean burning for greater efficiency and 30% NOx margin to CAEP/8. The compressor and high pressure turbine are made from powdered metal . The low-pressure turbine airfoils made of titanium aluminide (TiAl) are stronger, lighter, and more durable than nickel -based parts. 3D printing

10549-427: The engine must generate enough power to drive the fan at its rated mass flow and pressure ratio. Improvements in turbine cooling/material technology allow for a higher (HP) turbine rotor inlet temperature, which allows a smaller (and lighter) core, potentially improving the core thermal efficiency. Reducing the core mass flow tends to increase the load on the LP turbine, so this unit may require additional stages to reduce

10686-431: The engine's list price was US$ 41.4M. The first engine was expected to be ground-tested in 2016, with flight testing to begin in 2017 and certification happening in 2018. Because of the delays, the first flight test occurred in March 2018, with certification expected in late 2019. The first engine to test (FETT) completed its first run in April 2016. This engine completed 375 cycles in 335 hours run-time, which validated

10823-524: The exhaust velocity to a value closer to that of the aircraft. The Rolls-Royce Conway , the world's first production turbofan, had a bypass ratio of 0.3, similar to the modern General Electric F404 fighter engine. Civilian turbofan engines of the 1960s, such as the Pratt & Whitney JT8D and the Rolls-Royce Spey , had bypass ratios closer to 1 and were similar to their military equivalents. The first Soviet airliner powered by turbofan engines

10960-416: The expected first delivery of the aircraft had slipped to 2026, following development challenges and workplace strikes at the company. Emirates cast doubt on this forecast, noting that Boeing had no clear timeline for resuming certification flights. The 777X has a longer composite wing with folding wingtips. Due to this, the 777X is the first aircraft to have 'Wingtip Controls' inside the cockpit. Based on

11097-494: The fan nozzle. The amount of energy transferred depends on how much pressure rise the fan is designed to produce (fan pressure ratio). The best energy exchange (lowest fuel consumption) between the two flows, and how the jet velocities compare, depends on how efficiently the transfer takes place which depends on the losses in the fan-turbine and fan. The fan flow has lower exhaust velocity, giving much more thrust per unit energy (lower specific thrust ). Both airstreams contribute to

11234-598: The first aircraft to be delivered in 2026. In 2011, Boeing refined its response to the revamped Airbus A350 XWB with three 777X models, targeting a firm configuration in 2015, flying in late 2017 or 2018, and entering service by 2019. The then-proposed, 407–passenger 777-9X stretched the 777-300ER by four frames to 250 ft 11 in (76.48 m) in length, for a 759,000 lb (344 t) maximum take-off weight (MTOW). It would have been powered by 99,500 lbf (443 kN) engines, targeting per-seat 21% better fuel burn and 16% better operating cost. Early designs of

11371-450: The first fan rotor stage. This improves the fan surge margin (see compressor map ). Since the 1970s, most jet fighter engines have been low/medium bypass turbofans with a mixed exhaust, afterburner and variable area exit nozzle. An afterburner is a combustor located downstream of the turbine blades and directly upstream of the nozzle, which burns fuel from afterburner-specific fuel injectors. When lit, large volumes of fuel are burnt in

11508-413: The first had explored the flight envelope for nearly 100 hours. After the first delivery was pushed back from 2021 to 2022, the third aircraft made its maiden flight on August 3; it is slated for avionics systems, APU, flight loads and propulsion performance tests. In January 2021, Boeing expected to add two more 777-9s to the test program, aiming for certification in 2021. In early 2021, first delivery

11645-711: The first prototype began low-speed taxi tests. On July 24, Boeing announced that the GE9X engine issue would delay the maiden flight until 2020. The company continued to target first deliveries in 2020, though it intends to boost production of current-generation 777 freighters in 2020. GE Aviation in Ohio is recalling four GE9X turbofans from Boeing in Washington state in Antonov An-124 freighters from Volga-Dnepr Airlines , mounted in 26 x 14 x 13 ft (8 x 4 x 4 m), 36,000 lb (16.3 t) stands. On September 5, in

11782-616: The folding wingtip actuation system made by Liebherr Aerospace . The mechanism was demonstrated for Aviation Week at the Boeing Everett Factory in October 2016; the folding movement should be complete in 20 seconds and be locked in place at the end. Specific alerts and procedures are needed to handle a malfunction. As existing regulations do not cover the folding wingtips, the FAA issued special conditions, including proving their load-carrying limits, demonstrating their handling qualities in

11919-605: The foundation for the company's expected future programs: the New Midsize Airplane (NMA) and later the New Small Airplane to replace the 737. In February 2018, Subaru (ex–Fuji Heavy Industries) completed the first aluminum and titanium center wingbox integrated with main landing gear wheel wells at its Handa factory. The factory was completed in April 2016 and started operation in 2017. It has 125,000 square feet (11,600 m ) of floor space and

12056-496: The fuel used to move the aircraft forwards. A turbofan harvests that wasted velocity and uses it to power a ducted fan that blows air in bypass channels around the rest of the turbine. This reduces the speed of the propelling jet while pushing more air, and thus more mass. The other penalty is that combustion is less efficient at lower speeds. Any action to reduce the fuel consumption of the engine by increasing its pressure ratio or turbine temperature to achieve better combustion causes

12193-429: The gross thrust of the engine. The additional air for the bypass stream increases the ram drag in the air intake stream-tube, but there is still a significant increase in net thrust. The overall effective exhaust velocity of the two exhaust jets can be made closer to a normal subsonic aircraft's flight speed and gets closer to the ideal Froude efficiency . A turbofan accelerates a larger mass of air more slowly, compared to

12330-474: The hot nozzle to convert to kinetic energy. Turbofans represent an intermediate stage between turbojets , which derive all their thrust from exhaust gases, and turbo-props which derive minimal thrust from exhaust gases (typically 10% or less). Extracting shaft power and transferring it to a bypass stream introduces extra losses which are more than made up by the improved propulsive efficiency. The turboprop at its best flight speed gives significant fuel savings over

12467-510: The initial -9, a static test airframe , were underway in the purpose-built wing center near Everett, Washington . Four -9s, a fatigue-test airframe, and two -8s were planned for testing. Tests of avionics , power and integrated systems continue in Boeing Field laboratories and were integrated into an "Airplane Zero" in 2017 as 70% detailed design was done by June 2017. The assembly of the first composite wing test example began in Everett in late September 2017 with its top section lowered into

12604-427: The larger airliner, the net fuel efficiency gain is projected to be 12 to 13%. Ten-abreast seating instead of nine with a longer fuselage enable a reduction in fuel burn per seat of 20% compared to the 365-seat 777-300ER. The longer-range, 355-seat 777-8 should have a 13% improvement in fuel consumption with 10 fewer seats than the -300ER. Boeing forecast a 33% better cost per seat than the 747-400 and 13% better than

12741-452: The limit load, the aluminum skin ruptured under the center fuselage, aft of the wing, and the damaged structure extended up the fuselage side to a passenger plug door which blew out − and not an outward-hinged cargo door. In October 2019, the JATR board created to review the Boeing 737 MAX certification noted that the FAA would need to assess more thoroughly how modifications interact with

12878-417: The low pressure (LP) fan and booster to spin faster to better match its speed with the LP turbine. The fan blades feature steel leading edges and fiberglass trailing edges to better absorb bird strikes with more flexibility than carbon fiber. Fourth generation carbon fiber composite materials, comprising the bulk of the fan blades, make them lighter, thinner, stronger, and more efficient. The GE9X also uses

13015-506: The main FAL in the early 2020s. The first -9 roll-out is due in late 2018 and all four -9 prototypes are to join the flight tests by mid-2019, while the two -8 prototypes were to be assembled in 2020 before deliveries. The first wing was completed in May for static tests before the flight test wings. By July 2018, 98% of its engineering had been released. By September, the static test 777X article

13152-417: The mechanical power produced by the turbine. In a bypass design, extra turbines drive a ducted fan that accelerates air rearward from the front of the engine. In a high-bypass design, the ducted fan and nozzle produce most of the thrust. Turbofans are closely related to turboprops in principle because both transfer some of the gas turbine's gas power, using extra machinery, to a bypass stream leaving less for

13289-400: The next iteration of engine technology. The first-stage HP turbine shroud , the first- and second-stage HP turbine nozzles and the inner and outer combustor linings are made from CMC, only static components, operating 500 °F (260 °C) hotter than nickel alloys with some cooling. CMCs have twice the strength at one-third the weight of metal and require 59% less cooling. In total,

13426-483: The number of extra compressor stages required, and variable geometry stators enable high-pressure-ratio compressors to work surge-free at all throttle settings. The first (experimental) high-bypass turbofan engine was the AVCO-Lycoming PLF1A-2, a Honeywell T55 turboshaft-derived engine that was first run in February 1962. The PLF1A-2 had a 40 in diameter (100 cm) geared fan stage, produced

13563-431: The presence of FAA inspectors, a door blew off on the 777X static test airframe during the ultimate load test, which is conducted with the airplane stressed and pressurized beyond normal operating limits. Depending on the outcome of its root cause investigation, Boeing should have time to modify the failed part and repeat the test during the margin from the existing engine-related delays. At 99% of ultimate load, 1.48 times

13700-452: The previously expected June 26 by a stator problem at the front of the 11-stage high-pressure compressor . Before certification, final tests included a full durability block test, replacing the usual "triple redline" test at maximum EGT and both rotor speeds, as modern high-bypass ratio engines cannot achieve all maximum conditions near sea level. The high-pressure compressor stator redesign delayed engine certification into autumn, which delayed

13837-467: The required thrust still maintained by increasing the mass accelerated. A turbofan does this by transferring energy available inside the engine, from the gas generator, to a ducted fan which produces a second, additional mass of accelerated air. The transfer of energy from the core to bypass air results in lower pressure and temperature gas entering the core nozzle (lower exhaust velocity), and fan-produced higher pressure and temperature bypass-air entering

13974-399: The same helicopter weight can be supported by a high power engine and small diameter rotor or, for less fuel, a lower power engine and bigger rotor with lower velocity through the rotor. Bypass usually refers to transferring gas power from a gas turbine to a bypass stream of air to reduce fuel consumption and jet noise. Alternatively, there may be a requirement for an afterburning engine where

14111-494: The slip should not change the engine certification schedule or the first flight of the 777X. The flight-test engines were to be shipped later in 2018, before the year-end roll out and first flight expected in February 2019. During the component development, two temporary engines were to be placed on the first flight-test aircraft. Wing assembly is difficult, with the light but strong carbon-fiber material being less forgiving than traditional aluminum, and aircraft systems integration in

14248-454: The smaller TF34 . More recent large high-bypass turbofans include the Pratt & Whitney PW4000 , the three-shaft Rolls-Royce Trent , the General Electric GE90 / GEnx and the GP7000 , produced jointly by GE and P&W. The Pratt & Whitney JT9D engine was the first high bypass ratio jet engine to power a wide-body airliner. 777-9 The Boeing 777X is the latest series of

14385-509: The smaller 353-seat 777-8X proposed stretching the 777-200ER by ten frames to a length of 228 ft 2 in (69.55 m), with a 694,000 lb (315 t) MTOW and 88,000 lbf (390 kN) turbofans to compete with the A350-900. An 8LX version with the 9X's MTOW would have had a range of 9,480 nmi (17,560 km; 10,910 mi). The current 777-200LR/300ER has a 775,000 lb (352 t) MTOW. The proposals also included

14522-502: The sole requirement for bypass is to provide cooling air. This sets the lower limit for BPR and these engines have been called "leaky" or continuous bleed turbojets (General Electric YJ-101 BPR 0.25) and low BPR turbojets (Pratt & Whitney PW1120). Low BPR (0.2) has also been used to provide surge margin as well as afterburner cooling for the Pratt & Whitney J58 . Propeller engines are most efficient for low speeds, turbojet engines for high speeds, and turbofan engines between

14659-454: The speed of the propelling jet has to be reduced because there is a price to be paid in producing the thrust. The energy required to accelerate the gas inside the engine (increase in kinetic energy) is expended in two ways, by producing a change in momentum ( i.e. a force), and a wake which is an unavoidable consequence of producing thrust by an airbreathing engine (or propeller). The wake velocity, and fuel burned to produce it, can be reduced and

14796-536: The technology and materials available at the time. The first turbofan engine, which was only run on a test bed, was the German Daimler-Benz DB 670 , designated the 109-007 by the German RLM ( Ministry of Aviation ), with a first run date of 27 May 1943, after the testing of the turbomachinery using an electric motor, which had been undertaken on 1 April 1943. Development of the engine

14933-497: The thrust equation can be expanded as: F N = m ˙ e v h e − m ˙ o v o + B P R ( m ˙ c ) v f {\displaystyle F_{N}={\dot {m}}_{e}v_{he}-{\dot {m}}_{o}v_{o}+BPR\,({\dot {m}}_{c})v_{f}} where: The cold duct and core duct's nozzle systems are relatively complex due to

15070-673: The trailing edges of some jet engine nozzles that are used for noise reduction . The shaped edges smooth the mixing of hot air from the engine core and cooler air flowing through the engine fan, which reduces noise-creating turbulence. Chevrons were developed by GE under a NASA contract. Some notable examples of such designs are Boeing 787 and Boeing 747-8  – on the Rolls-Royce Trent 1000 and General Electric GEnx engines. Early turbojet engines were not very fuel-efficient because their overall pressure ratio and turbine inlet temperature were severely limited by

15207-428: The turbine inlet temperature is not too high to compensate for the smaller core flow. Future improvements in turbine cooling/material technology can allow higher turbine inlet temperature, which is necessary because of increased cooling air temperature, resulting from an overall pressure ratio increase. The resulting turbofan, with reasonable efficiencies and duct loss for the added components, would probably operate at

15344-425: The turbojet uses the gas from its thermodynamic cycle as its propelling jet, for aircraft speeds below 500 mph there are two penalties to this design which are addressed by the turbofan. Firstly, energy is wasted as the propelling jet is going much faster rearwards than the aircraft is going forwards, leaving a very fast wake. This wake contains kinetic energy that reflects the fuel used to produce it, rather than

15481-445: The turbojet, is lost. In contrast, Roth considers regaining this independence the single most important feature of the turbofan which allows specific thrust to be chosen independently of the gas generator cycle. The working substance of the thermodynamic cycle is the only mass accelerated to produce thrust in a turbojet which is a serious limitation (high fuel consumption) for aircraft speeds below supersonic. For subsonic flight speeds

15618-453: The turbojet. This is done mechanically by adding a ducted fan rather than using viscous forces. A vacuum ejector is used in conjunction with the fan as first envisaged by inventor Frank Whittle . Whittle envisioned flight speeds of 500 mph in his March 1936 UK patent 471,368 "Improvements relating to the propulsion of aircraft", in which he describes the principles behind the turbofan, although not called as such at that time. While

15755-476: The two flows may combine within the ducts, and share a common nozzle, which can be fitted with afterburner. Most of the air flow through a high-bypass turbofan is lower-velocity bypass flow: even when combined with the much-higher-velocity engine exhaust, the average exhaust velocity is considerably lower than in a pure turbojet. Turbojet engine noise is predominately jet noise from the high exhaust velocity. Therefore, turbofan engines are significantly quieter than

15892-418: The two. Turbofans are the most efficient engines in the range of speeds from about 500 to 1,000 km/h (270 to 540 kn; 310 to 620 mph), the speed at which most commercial aircraft operate. In a turbojet (zero-bypass) engine, the high temperature and high pressure exhaust gas is accelerated when it undergoes expansion through a propelling nozzle and produces all the thrust. The compressor absorbs

16029-560: The ultra-long-range 777-200LR and compete with the Airbus A350-1000 . Production of the -8 was expected to follow the -9 around two years later. It was expected to be the basis of a freighter version which would be available 18 to 24 months after the introduction of the -8. The 777-8 should feature a 13,000 lb (5.9 t) higher MTOW over the 775,000 lb (352 t) of the 777-9, for an improved range from 8,690 to 9,460 nmi (16,090 to 17,520 km). Due to

16166-510: The use of two separate exhaust flows. In high bypass engines, the fan is situated in a short duct near the front of the engine and typically has a convergent cold nozzle, with the tail of the duct forming a low pressure ratio nozzle that under normal conditions will choke creating supersonic flow patterns around the core . The core nozzle is more conventional, but generates less of the thrust, and depending on design choices, such as noise considerations, may conceivably not choke. In low bypass engines

16303-411: The wing assembly. At this time, 93–95% of the design was released: complete for structures and in progress for systems and engine installation before interiors. Fuselage subassemblies started shipping on February 7: aft fuselage panels from Mitsubishi Heavy Industries, center and forward fuselage panels from Kawasaki Heavy Industries and the 11/45 center wingbox from Subaru. In March, fuselage assembly

16440-467: The wing on the Boeing 747-400 with its larger main gear struts and bigger tires and not the previous 747-100 GE testbed. The engine was tilted 5° more than the GE CF6 . Boeing built a specially designed pylon for the testbed. Suspended on a 19 ft (580 cm) strut, the fourth engine of the program began flight testing at the end of 2017. The engine, with a fan diameter of 134 in (340 cm),

16577-701: The world, with an experience base of over 10 million service hours. The CF700 turbofan engine was also used to train Moon-bound astronauts in Project Apollo as the powerplant for the Lunar Landing Research Vehicle . A high-specific-thrust/low-bypass-ratio turbofan normally has a multi-stage fan behind inlet guide vanes, developing a relatively high pressure ratio and, thus, yielding a high (mixed or cold) exhaust velocity. The core airflow needs to be large enough to ensure there

16714-614: Was abandoned with its problems unsolved, as the war situation worsened for Germany. Later in 1943, the British ground tested the Metrovick F.3 turbofan, which used the Metrovick F.2 turbojet as a gas generator with the exhaust discharging into a close-coupled aft-fan module comprising a contra-rotating LP turbine system driving two co-axial contra-rotating fans. Improved materials, and the introduction of twin compressors, such as in

16851-419: Was completed, lacking engines and various systems, ahead of its structural testing on ground. The first join on the static-test aircraft was done in 16 days instead of the planned 20 and lessons learned from the 787 wing-body join led to a single defect instead of the hundreds usual in new models. The final body join of the first flight test aircraft was completed by November, before an early 2019 rollout and

16988-425: Was delayed while the engines are modified to a final certifiable configuration. As of 17 June 2019 , GE expressed confidence that the engine would receive certification during the fall and that the first flight of the 777X would still occur in 2019. The 777X test plan was later revised as several months are required to develop and test fixes to the GE9X, and first flight slipped to October–November. By June,

17125-660: Was derived from the General Electric J85/CJ610 turbojet 2,850 lbf (12,700 N) to power the larger Rockwell Sabreliner 75/80 model aircraft, as well as the Dassault Falcon 20 , with about a 50% increase in thrust to 4,200 lbf (19,000 N). The CF700 was the first small turbofan to be certified by the Federal Aviation Administration (FAA). There were at one time over 400 CF700 aircraft in operation around

17262-480: Was designed to improve fuel efficiency by 10% compared to the GE90. It is rated at 110,000 lbf (490 kN) of thrust, which is 5,000 lbf (20 kN) less than the GE90 highest thrust variant, the GE90-115, rated at 115,000 lbf (510 kN). In February 2012, GE announced studies on a more efficient derivative of the GE90, calling it the GE9X, to power both the -8 and -9 variants of the new Boeing 777X . It

17399-514: Was developed and quietly tested in Anacortes, Washington , 40 miles north of the 777 Everett assembly plant. A major leap in automated production , it drills the tens of thousands of holes in the fuselage more quickly, accurately, and safely. The wings are the first produced by Boeing in composite and not out-sourced like for the 787, and production is largely automated as well. The specifically built billion-dollar factory has excess capacity, laying

17536-486: Was expected to be completed in 2017 as avionics, power and other systems are ready for ground tests. Aircraft Numbers 1 and 6 were planned to be used for ground tests; four 777-9s (No. 2 to 5) were slated for the flight test and certification campaign, with two 777-8s to come later. Final assembly was planned to start in 2018 before roll-out the same year. The 777X production techniques were expected to be major cost-cutters. The Fuselage Automated Upright Build (FAUB) system

17673-501: Was expecting its first deliveries in 2026. As of September 2024, its estimate has been revised to an entry into service by early 2027. In August 2024, routine inspection following a test flight in Hawaii led to Boeing grounding its 777X test fleet. A structural link between the engine and wing was found to be damaged, while cracks were found in the same component on other aircraft in the fleet. On October 11, 2024, Boeing confirmed that

17810-404: Was going to be loaded in early December. To position wings and fuselage sections, automated guided vehicles are replacing overhead cranes and "monuments" - large, permanent tooling fixtures . The primary systems were installed by December and its second GE9X engine were to be hung in early 2019. Engines were installed by early January 2019. The first 777-9 body join happened in February for

17947-558: Was modified as a result of early running experience. SETT testing started on May 16, 2017, at Peebles, Ohio , 13 months after FETT; it was the first engine built to the finalized production standard for certification. During the FAA 150 hr block test, the variable stator vane (VSV) lever arm failed and its redesign led to a 3–month delay. SETT was followed by four more test engines by May 2018. The certification program began in May 2017. Eight additional engines were involved for certification, as well as one for ETOPS certification installed in

18084-563: Was planned for the fourth quarter of 2018. On November 10, 2017, a GE9X engine reached a record thrust of 134,300 lbf (597 kN) in Peebles, a new Guinness World Record breaking the GE90-115B 127,900 lbf (569 kN) record set in 2002. The block test engine ran at its operational limits, at triple red-line conditions: maximum fan speed, maximum core speed, and maximum exhaust gas temperature . Icing tests started in Winnipeg at

18221-490: Was pushed to late 2023. The delay was due to updated type certification requirements and the impact of the COVID-19 pandemic on aviation , costing a $ 6.5 billion charge. On June 27, 2021, The Seattle Times reported on an FAA letter to Boeing dated May 13 delaying type certification until mid to late 2023, pushing deliveries to 2024. The FAA cited a serious test flight incident involving an "uncommanded pitch event" and

18358-489: Was scheduled to begin in the third quarter. By October 2018, half of the certification was completed, and eight development engines were used, mostly in Peebles, Ohio : #1 was stored; a fan blade was deliberately separated from the fan hub of #2 at takeoff thrust for the blade-out test; #3 was used for crosswind ground testing and cyclic and load testing of the thrust reverser cascade assembly; #4 explored boundaries of

18495-587: Was the Tupolev Tu-124 introduced in 1962. It used the Soloviev D-20 . 164 aircraft were produced between 1960 and 1965 for Aeroflot and other Eastern Bloc airlines, with some operating until the early 1990s. The first General Electric turbofan was the aft-fan CJ805-23 , based on the CJ805-3 turbojet. It was followed by the aft-fan General Electric CF700 engine, with a 2.0 bypass ratio. This

18632-473: Was to begin in Everett at a temporary production line between the current 747-8 and 777 assembly lines to avoid disrupting the 777-300ER production. The static airframe and the first flight-test aircraft bodies were to be joined in the second quarter of 2018 and in June–July, respectively. Scheduled for the start of 2018, the GE9X first flight has been delayed by the variable stator vane actuator arms redesign but

18769-568: Was to feature the same 128 in (325 cm) fan diameter as the GE90-115B with thrust decreased by 15,800 lbf (70 kN) to a new rating of 99,500 lbf (443 kN) per engine. The engine for the 777-8X was to be derated to 88,000 lbf (390 kN). In 2013, the fan diameter was increased by 3.5 in (9 cm) to 132 in (335 cm). In 2014, the fan diameter was increased another 1.5 in (4 cm) to 133.5 in (339 cm), slightly increasing thrust from 102,000 to 105,000 lbf (450 to 470 kN). In 2016,

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