Airbus A350

The Airbus A350 XWB is a family of long-range, twin-engine wide-body jet airliners developed by European aircraft manufacturer Airbus. The A350 is the first Airbus aircraft with both fuselage and wing structures made primarily of carbon-fibre-reinforced polymer. Its variants seat 280 to 366 passengers in typical three-class seating layouts. The A350 is positioned to succeed the A340, and compete with the Boeing 787 and 777.

The A350 was originally conceived in 2004, pairing the A330's fuselage with new aerodynamics features and engines. In 2006, Airbus redesigned the aircraft in response to criticism from several major prospective customers and renamed it the A350 XWB (extra wide body). Development costs are estimated at €11 billion (US$15 billion or £9.5 billion). , Airbus had received 821 orders for A350s from 46 customers worldwide. The prototype A350 first flew on 14 June 2013 from Toulouse, France. Type certification from the European Aviation Safety Agency was received in September 2014 and certification from the Federal Aviation Administration two months later. On 15 January 2015, the A350 entered service with Qatar Airways, the type's launch customer.

Early designs
Airbus initially rejected Boeing's claim that the Boeing 787 Dreamliner would be a serious threat to the Airbus A330, stating that the 787 was just a reaction to the A330, and that no response was needed. When airlines pushed Airbus to provide a competitor, Airbus initially proposed the A330-200Lite, a derivative of the A330 featuring improved aerodynamics and engines similar to those on the 787. The company planned to announce this version at the 2004 Farnborough Airshow, but did not proceed.

On 16 September 2004, then-Airbus president and CEO Noël Forgeard confirmed the consideration of a new project during a private meeting with prospective customers. Forgeard did not give a project name, and he did not state whether it would be an entirely new design or a modification of an existing product. The airlines were not satisfied, and Airbus committed €4 billion to a new airliner design. The original version of the A350 superficially resembled the A330 due to its common fuselage cross-section and assembly. A new wing, engines and a horizontal stabiliser were to be coupled with new composite materials and production methods applied to the fuselage to make the A350 an almost all-new aircraft. On 10 December 2004, the boards of EADS and BAE Systems, then the shareholders of Airbus, gave Airbus an "authorisation to offer (ATO)", and formally named it the A350.

On 13 June 2005 at the Paris Air Show, Middle Eastern carrier Qatar Airways announced that they had placed an order for 60 A350s. In September 2006 the airline signed a memorandum of understanding with General Electric to launch the GEnx-1A-72 for the aircraft. Emirates sought a more improved design and decided against ordering the initial version of the A350.

On 6 October 2005, the programme's industrial launch was announced with an estimated development cost of around €3.5 billion. The A350 was initially planned to be a 250- to 300-seat twin-engine wide-body aircraft derived from the existing A330's design. Under this plan, the A350 would have modified wings and new engines, while sharing the A330's fuselage cross-section. As a result of a controversial design, the fuselage was to consist primarily of aluminium-lithium, rather than the carbon-fiber-reinforced polymer (CFRP) fuselage on the 787. It was to see entry in two versions: the A350-800 capable of flying 8800 nmi with typical passenger capacity of 253 in three-class configuration and the 300-seat (3-class) A350-900 with 7500 nmi range. It was designed to be a direct competitor to the 787-9, and 777-200ER.

The A350 was publicly criticised by two of Airbus' largest customers, International Lease Finance Corporation (ILFC) and GE Capital Aviation Services (GECAS). On 28 March 2006, ILFC President Steven F. Udvar-Házy urged Airbus to pursue a clean-sheet design, or risk losing market share to Boeing, branding Airbus's strategy as "a Band-aid reaction to the 787", a sentiment echoed by GECAS president Henry Hubschman. In April 2006, while reviewing bids for the 787 and A350, CEO of Singapore Airlines (SIA) Chew Choon Seng, commented that: "Having gone through the trouble of designing a new wing, tail, cockpit... [Airbus] should have gone the whole hog and designed a new fuselage." Airbus responded by stating they were considering A350 improvements to satisfy customer demands, Airbus's then-CEO Gustav Humbert stated that: "Our strategy isn't driven by the needs of the next one or two campaigns, but rather by a long-term view of the market and our ability to deliver on our promises." As major airlines such as Qantas and Singapore Airlines selected the 787 over the A350, Humbert tasked an engineering team to produce new alternative designs; one such proposal, known internally as "1d", formed the basis of the A350 redesign.

Redesign and launch
On 14 July 2006, during the Farnborough Airshow, the redesigned aircraft was designated A350 XWB (Xtra-Wide-Body). There was some previous speculation that the revised aircraft would be called the Airbus A370 or A280, with Airbus going as far as accidentally publishing an advertisement referring to the model as the "A280" on the Financial Times's website. Within four days, Singapore Airlines agreed to order 20 A350XWBs with options for another 20 A350XWBs.

The proposed A350 was a new design, including a wider fuselage cross-section, allowing seating arrangements ranging from an eight-abreast low-density premium economy layout to a ten-abreast high-density seating configuration for a maximum seating capacity of 440–475 depending on variant. The A330 and previous iterations of the A350 would only be able to accommodate a maximum of eight seats per row. The 787 can accommodate eight to nine seats per row, while the 777 typically accommodates nine seats per row, with some airlines using a ten-abreast seating layout. The A350 cabin is 12.7 cm wider at the eye level of a seated passenger than the competing 787, and 28 cm narrower than the competing Boeing 777. (See Wide-body aircraft for a comparison of cabin widths and seating.) All A350 passenger models will have a range of at least 8000 nmi. The redesigned composite fuselage provides higher cabin pressure and humidity, and lower maintenance costs.

On 1 December 2006, the Airbus board of directors approved the industrial launch of the A350-800, -900, and -1000 variants. The delayed launch decision was a result of delays of the Airbus A380 and discussions on how to fund development. EADS CEO Thomas Enders stated that the A350 programme was not a certainty, citing EADS/Airbus's stretched resources. However, it was decided programme costs are to be borne mainly from cash-flow. First delivery for the A350-900 was scheduled for mid-2013, with the -800 and -1000 following on 12 and 24 months later, respectively. New technical details of the A350 XWB were revealed at a press conference in December 2006. John Leahy indicated existing A350 contracts were being re-negotiated due to price increases compared to the original A350s contracted. On 4 January 2007, Pegasus Aviation Finance Company placed the first firm order for the A350 XWB with an order for two aircraft.

The design change imposed a two-year delay into the original timetable and increased development costs from US$5.3 billion (€5.5B) to approximately US$10 billion (€9.7B). The total development cost for the A350 was estimated at US$15 billion by Reuters (€12 billion or £10 billion). The original mid-2013 delivery date of the A350 changed, as a longer than anticipated development forced Airbus to delay the final assembly and first flight of the aircraft to the third quarter of 2012 and second quarter of 2013 respectively. As a result, the flight test schedule was compressed from the original 15 months to 12 months. A350 programme chief Didier Evrard stressed that delays only affect the A350-900 while the -800 and -1000 schedules remain unchanged.

Design phase


Airbus suggested Boeing's use of composite materials for the 787 fuselage was premature, and that the new A350 XWB was to feature large carbon fibre panels for the main fuselage skin. After facing criticism for maintenance costs, Airbus confirmed in early September 2007 the adoption of composite fuselage frames for the aircraft structure. The composite frames would feature aluminium strips to ensure the electrical continuity of the fuselage (for dissipating lightning strikes). Airbus will use a full mock up fuselage to develop the wiring, a different approach from the A380, on which the wiring was all done on computers.

In 2006, Airbus confirmed development of a full bleed air system on the A350, as opposed to the 787's bleedless configuration. Rolls-Royce agreed with Airbus to supply a new variant of the Trent turbofan engine for the A350 XWB, named Trent XWB. In 2010, after low-speed wind tunnel tests, Airbus finalized the static thrust at sea level for all three proposed variants to the 330 - 420 kN range.

General Electric (GE) stated it would not offer the GP7000 engine on the aircraft, and that previous contracts for the GEnx on the original A350 did not apply to the XWB. Engine Alliance partner Pratt & Whitney seemed to be at odds with GE on this, having publicly stating that it was looking at an advanced derivative of the GP7000. In April 2007, Airbus former chief executive Louis Gallois held direct talks with GE management over developing a GEnx variant for the A350 XWB. In June 2007, Airbus's chief operating officer John Leahy indicated that the A350 XWB would not feature the GEnx engine, saying that Airbus wanted GE to offer a more efficient version for the airliner. Since then, the largest GE engines operators, which include Emirates, US Airways, Hawaiian Airlines and ILFC have selected the Trent XWB for their A350 orders. In May 2009, GE said that if it were to reach a deal with Airbus to offer the current 787-optimised GEnx for the A350, it would only power the -800 and -900 variants. GE believed it can offer a product that outperforms the Trent 1000 and Trent XWB, but was reluctant to support an aircraft competing directly with its GE90-115B-powered 777 variants.

In January 2008, French-based Thales Group won a US$2.9 billion (€2 billion) 20-year contract to supply avionics and navigation equipment for the A350 XWB, beating Honeywell and Rockwell Collins. US-based Rockwell Collins and Moog Inc were chosen to supply the horizontal stabiliser actuator and primary flight control actuation, respectively. The flight management system incorporated several new safety features. Regarding cabin ergonomics and entertainment, in 2006 Airbus signed a firm contract with BMW for development of an interior concept for the original A350. On 4 February 2010, Airbus signed a contract with Panasonic Avionics Corporation to deliver in-flight entertainment and communication (IFEC) systems for the Airbus A350 XWB.

Production


In 2008, Airbus planned to introduce new techniques and procedures to cut assembly time in half. The A350 XWB production programme sees extensive international collaboration and investments in new facilities: Airbus constructed 10 new factories in Western Europe and the US, with extensions carried out on 3 further sites.

Among the new buildings was a £570 million (US$760 million or €745 million) composite facility in Broughton, Wales, which would be responsible for the wings. In June 2009, the National Assembly for Wales announced provision of a £28 million grant to provide a training centre, production jobs and money toward the new production centre.

Airbus manufactured the first structural component in December 2009. Production of the first fuselage barrel began in late 2010 at its production plant in Illescas, Spain. Construction of the first A350-900 centre wingbox was set to start in August 2010.

The new composite rudder plant in China opened in early 2011. The forward fuselage of the first A350 was delivered to the factory on 29 December 2011. Final assembly of the first A350 static test model was started on 5 April 2012. Final assembly of the first prototype A350 was completed in December 2012.

The production rate should rise from three aircraft per month in early 2015 to five at the end of 2015, and should ramp to ten aircraft per month by 2018. 17 planes should be delivered in 2015, and the initial dispatch reliability is 98%.

Testing and certification


The first Trent engine test was made on 14 June 2010. The Trent XWB's flight test programme began use on the A380 development aircraft in early 2011, ahead of engine certification in late 2011. On 2 June 2013, the Trent XWB engines were powered up on the A350 for the first time. Airbus confirmed that the flight test programme would last 12 months and use five test aircraft.

The A350's maiden flight took place on 14 June 2013 from the Toulouse–Blagnac Airport. Airbus's chief test pilot said, "it just seemed really happy in the air...all the things we were testing had no major issues at all."

A350 XWB, F-WWCF, msn. 2, underwent two-and-a-half weeks of climatic tests in the unique McKinley Climatic Laboratory at Eglin Air Force Base, Florida, in May 2014, and was subjected to multiple climatic and humidity settings from a high of 45 °C to as low as -40 °C.

The A350 received type certification from the European Aviation Safety Agency (EASA) on 30 September 2014. On 15 October 2014, EASA approved the A350-900 for ETOPS 370, allowing it to fly more than six hours on one engine and making it the first airliner to be approved for "ETOPS Beyond 180 minutes" before entry into service. Later that month Airbus received regulatory approval for a Common Type Rating for pilot training between the A350 XWB and A330. On 12 November 2014, the A350 received certification from the US Federal Aviation Administration.

Introduction and early operations


In June 2011, the A350-900 was scheduled to enter service in the first half of 2014, with the -800 to enter service in mid-2016, and the -1000 in 2017. In July 2012, Airbus delayed the -900's introduction by three months to the second half of 2014. The first delivery to launch customer Qatar Airways took place on 22 December 2014. The first commercial flight was made on 15 January 2015 between Doha and Frankfurt.

One year after introduction, the A350 fleet accumulated 3,000 cycles and around 16,000 flight hours. Average daily utilization of the A350 across first customer was 11.4 hours with flights averaging 5.2 hours, under the aircraft's capabilities, and reflect both short flights within the schedules of Qatar Airways and Vietnam Airlines, as well as flight-crew proficiency training that is typical of early utilization and is accomplished on short-haul flights. Finnair is operating the A350 at very high rate: 15 flight hours per day for Beijing, 18 hours for Shanghai, more than 20 hours for Bangkok and may accelerate its retirement of Airbus A340 aircraft as a result.

Teething problems in service have so far included three areas: The onboard Maintenance, Repair, Overhaul (MRO) network needed software improvements; Airbus issued service bulletins regarding onboard equipment and removed galley inserts (coffee makers, toaster ovens) because of leaks; and has had to address spurious overheating warnings in the bleed air system by retrofitting an original connector with a gold-plated connector. Airbus targets a 98.5% dependability by the end of 2016 and to match the mature A330 reliability by early 2019.

By the end of May 2016, the in-service fleet flew 55,200 hours over 9,400 cycles at 97.8% operational reliability on three months. The longest operated sector was Qatar Airways' Adelaide-Doha at 13.8 h for 6,120 nmi, 45% of flights were under 3,000 nmi, 16% over 5,000 nmi and 39% in between. The average flight was 6.8 h, the longest average was TAM Airlines with 9.6 h and the shortest was Cathay Pacific's 2.1h to build experience on the type. Aircraft seat configuration range from 253 seats for Singapore Airlines to 348 seats with TAM, with a 30 to 46 seat business class and a 211 to 318 seat economy class, often including a premium economy.

The first A350-1000 was assembled in 2016, for a first flight on 24 November and entry into service expected in mid-2017.

In January 2017, two years after introduction, 62 aircraft are in service with 10 airlines; they accumulated 25,000 flights over 154,000 hours with an average daily utilisation of 12.5 hours, and transported six million passengers with a 98.7% operational reliability.

Overview
In September 2007, Airbus rolled out new design advances to a gathering of 100 representatives from existing and potential XWB customers. The A350 XWB is based on the technologies developed for Airbus A380 and includes a similar cockpit and fly-by-wire systems layout.

Airbus expects 10% lower airframe maintenance compared with the original A350 design and 14% lower empty seat weight than the Boeing 777. Design freeze for the A350-900 was achieved in December 2008.

Materials
The A350 XWB airframe will be made out of 53% composites: carbon fibre reinforced plastic for the outer and centre wing box (covers, stringers, spars), fuselage (skin, frame, keel beam, and rear fuselage) and the empennage (horizontal and vertical tailplanes); 19% aluminium and Al-Li for ribs, floor beams and gear bays; 14% titanium for landing gears, pylons and attachments; 6% steel and 8% miscellaneous. The A350's competitor, the Boeing 787 is 50% composites, 20% aluminium, 15% titanium, 10% steel, and 5% other.

Fuselage


The new XWB fuselage has a constant width from door 1 to door 4, unlike previous Airbus aircraft, to provide maximum usable volume. The double-lobe (ovoid) fuselage cross-section has a maximum outer diameter of 5.97 m, compared to 5.64 m for the A330/A340. The cabin's internal diameter will be 5.61 m wide at armrest level compared with 5.49 m in the Boeing 787 and 5.87 m in the Boeing 777. It allows for an eight-abreast 2–4–2 arrangement in a premium economy layout, with the seats being 49.5 cm wide between 5 cm wide arm rests. Airbus says that the seat width will be 1.3 cm greater than a 787 seat in the equivalent configuration. In the nine-abreast, 3–3–3 standard economy layout, the XWB's seat width will be 45 cm which will be 1.27 cm wider than the equivalent seat layout for the 787, and 3.9 cm wider than the equivalent A330 layout. The current 777 and future derivatives have 1.27 cm greater seat width than the A350 in a nine-abreast configuration. The 10-abreast seating on the A350 is similar to a 9-abreast configuration on the A330, with a seat width of 41.65 cm. Overall, Airbus promises passengers more headroom, larger overhead storage space and wider panoramic windows than current Airbus models.

The XWB's nose section will adopt a configuration derived from the A380 with a forward-mounted nosegear bay and a six-panel flightdeck windscreen. This differs substantially from the four-window arrangement in the original design. The new nose will improve aerodynamics and enable overhead crew rest areas to be installed further forward and eliminate any encroachment in the passenger cabin. The new windscreen has been revised to improve vision by reducing the width of the centre post. The upper shell radius of the nose section has been increased. The nose is likely to be constructed from aluminium but Airbus is currently running trade-off studies considering a one-piece carbon fibre structure. According to Gordon McConnell, A350 Chief Engineer, a carbon fibre structure would need titanium reinforcements for birdstrike protection, thus the aluminium structure is the best cost-wise.

Undercarriage


Airbus adopted a new philosophy for the attachment of the A350s main undercarriage as part of the switch to a composite wing structure. Each main undercarriage leg is attached to the rear wing spar forward and to a gear beam aft, which itself is attached to the wing and the fuselage. To help reduce the loads further into the wing, a double side-stay configuration has been adopted. This solution resembles the design of the Vickers VC10.

Airbus devised a three-pronged main undercarriage design philosophy encompassing both four- and six-wheel bogies to ensure it can keep the pavement loading within limits. The A350-800 and A350-900 will both have four-wheel bogies, although the −800's will be slightly shorter to save weight. Both will fit in the same 4.1 m long bay. The higher weight variant, the A350-1000 (and the A350-900R, which is being proposed to British Airways, as the −900 size but with sufficient fuel capacity to allow nonstop London-Sydney flights) will use a six-wheel bogey, with a 4.7 m undercarriage bay. French-based Messier-Dowty will provide the main undercarriage for the -800 and -900 variants, and UTC Aerospace Systems will supply the −1000 variant. The nose gear will be supplied by Liebherr-Aerospace.

Wing


The A350 features new composite wings with a wingspan that is common to the proposed variants. Its 64.75 m wingspan stays within the ICAO Aerodrome Reference Code E 65m limit, as the A330/A340, as are the Boeing 777. The A350's wing has a 31.9° sweep angle for a Mach 0.85 cruise speed and have a maximum operating speed of Mach 0.89.

It covers a 442 m2 area. This is between the 436.8 m2 wing of the current Boeing 777-200LR/300ER and the 466.8 m2 wing of the in-development Boeing 777X. However, Boeing and Airbus doesn't have the same measurement area. The A350-1000 wing will be 4% larger through a trailing edge extension.

A new trailing-edge high-lift device has been adopted with an advanced dropped-hinge flap similar to that of the Airbus A380, which permits the gap between the trailing edge and the flap to be closed with the spoiler. It is a limited morphing wing with adaptive features for continuously optimising the wing loading to reduce fuel burn : variable camber for longitudinal load control where inboard & outboard flaps deflect together and differential flaps setting for lateral load control where inboard & outboard flaps deflect differentially.

The manufacturer has extensively used computational fluid dynamics and also carried out more than 4,000 hours of low- and high-speed windtunnel testing to refine the aerodynamic design. The final configuration of wing and winglet was achieved for the "Maturity Gate 5" on 17 December 2008. The wingtip device curves upwards over the final 4.4 m.

The wings are produced in the new £400M, 46000 m2 North Factory at Airbus Broughton, employing 650 workers, in a specialist facility constructed with £29M of support from the Welsh Assembly Government.

Cockpit and avionics


The revised design of the A350 XWB's glass cockpit dropped the A380-sized display and adopted 38 cm liquid-crystal display screens. The new six-screen configuration includes two central displays mounted one above the other (the lower one above the thrust levers) and a single (for each pilot) primary flight/navigation display, with an adjacent on-board information system screen. Airbus says the cockpit design allows for future advances in navigation technology to be placed on the displays plus gives flexibility and capacity to upload new software and to combine data from multiple sources and sensors for flight management and aircraft systems control. A head-up display is also present in the cockpit.

The avionics is a further development of the integrated modular avionics (IMA) concept found on the A380. The A350's IMA will manage up to 40 functions (versus 23 functions for the A380) such as undercarriage, fuel, pneumatics, cabin environmental systems, and fire detection. Airbus stated that the benefits includes reduced maintenance and lower weight because as the IMA replaces multiple processors and LRUs with around 50% fewer standard computer modules known as line-replaceable modules. The IMA runs on a 100 Mbit/s network based on the AFDX standard, as employed in the A380, in place of the architecture used on the A330/A340.

Powerplant


The Rolls-Royce Trent XWB feature a 118 in fan disk diameter and the design will be based on the advanced developments of the Airbus A380 Trent 900 and the Boeing 787 Trent 1000. It has two thrust levels to power the A350 variants : a 84000 lbf for the A350-900 and a 97000 lbf for the A350-1000. The higher-thrust version will have some modifications to the fan module—it will be the same diameter but will run slightly faster and have a new fan blade design—and run at increased temperatures allowed by new materials technologies from Rolls-Royce's research.

The Trent XWB may also benefit from the next-generation reduced acoustic mode scattering engine duct system (RAMSES), an acoustic quieting engine nacelle intake and a carry-on design of the Airbus's "zero splice" intake liner developed for the A380. A 'hot and high' rating option for Middle Eastern customers Qatar Airways, Emirates, and Etihad Airways keep its thrust available at higher temperatures and altitudes.

Airbus is aiming to certify the A350 with 350-minute ETOPS capability on entry into service. That could reach 420 min later. Engine thrust-reversers and nacelles will be supplied by US-based UTC Aerospace Systems.

Systems
The A350 XWB features a 1268 kW Honeywell HGT1700 auxiliary power unit, which has 10% greater power density than the previous generation of Honeywell's 331 APU family. Honeywell will also supply the air management system: the bleed air, environmental control, cabin pressure control and supplemental cooling systems. Airbus says that the new design provides a better cabin atmosphere with 20% humidity, a typical cabin altitude at or below 6000 ft and an airflow management system that adapts cabin airflow to passenger load with draught-free air circulation.

The ram air turbine, capable of generating 100 kVA, is supplied by Hamilton Sundstrand and located in the lower surface of the fuselage. In light of the Boeing 787 Dreamliner battery problems, in February 2013 Airbus decided to revert from lithium-ion to the proven nickel-cadmium technology although the flight test programme will continue with the lithium-ion battery systems.

Parker Hannifin supplies the complete fuel package: inerting system, fuel measurement and management systems, mechanical equipment and fuel pumps. The fuel tank inerting system features air-separation modules to generate nitrogen-enriched air to reduce the flammability of fuel vapour in the tanks. Parker also provides hydraulic power generation and distribution system: reservoirs, manifolds, accumulators, thermal control, isolation, software and new engine- and electric motor-driven pump designs. Parker estimates the contracts will generate more than $2 billion in revenues over the life of the programme.

Variants


The three main variants of the A350 were launched in 2006, with entry into service planned for 2013. At the 2011 Paris Air Show, Airbus postponed the entry into service of the A350-1000 by two years to mid-2017. In July 2012, the A350's entry into service was delayed to the second half of 2014, before the -900 began service on 15 January 2015. In October 2012, the -800 was due to enter service in mid-2016, but its development has been cancelled since September 2014. The A350 is also offered as the ACJ350 corporate jet by Airbus Corporate Jets, offering a 10800 nmi range for 25 passengers for the -900 derivative.

A350-900


The 280 tons MTOW A350-900 is the first A350 model and typically seats 325 passengers over a 8100 nmi range. Airbus says that per seat, the Boeing 777-200ER should have a 16% heavier MWE, a 30% higher block fuel consumption and 25% higher cash operating costs than the A350-900. The −900 is designed to compete with the Boeing 777, and 787, while replacing the Airbus A340-300 and A340-500.

The A350−900R extended-range variant was proposed featuring the higher engine thrust, strengthened structure, and landing gear of the 308 tons MTOW -1000 to give a further 800 nmi range. An A350−900F freighter with a 5000 nmi range and a similar payload and volume to the 91.7 t and 440 m³ MD-11F should be studied after the -1000 is done and if there is market demand.

After the Boeing 787-10 launch at the 2013 Paris Air Show, Airbus was discussing with airlines a possible -900 Regional with reduced MTOW to 250 tonnes and 2×75,000 lbf thrust. Etihad Airways was interested in this version optimized for routes of up to 6800 nmi and seating up to 360 passengers in a single class layout.

Philippine Airlines will replace its A340-300 with an A350-900HGW high gross weight version available from 2017 enabling non-stop Manila-New York without payload limitations in both directions, a 7404 nmi flight. The PAL version will have a 278 t MTOW and from 2020 the -900 will be proposed with the ULR 280 t MTOW, up from 268 t for the original weight variant and 260 t, 272 t, and 275 t certification variants, with the large fuel capacity. This will enable a 8,100 nmi range with 325 seats in business, premium, and economy classes.

A350-900ULR
The ultra-long range -900ULR MTOW will be increased to 280 tonnes and its fuel capacity from 141,000 litres to 165,000 litres within existing fuel tanks to enable up to 19-hour flights. The launch customer Singapore Airlines ordered seven aircraft, and will use these for non-stop flights from Singapore to New York and cities on the U.S. West Coast. Seating is reduced from 300 seats in Singapore Airlines standard A350 configuration to seat 170, but the plane could be reconfigured. Singapore Airlines is expected to take delivery of the aircraft in 2018.

At the 2015 Dubai Air Show, Airbus' John Leahy noted the appetite from the gulf carriers for the variant. The MTOW increase is 5 t from the previously certified 275 t variant. As the A350-900 fuel consumption is 5.8 t/hr, it needs an additional 24 tonnes of fuel to fly 19 hours instead of the standard 15 hours, gained through MTOW increase and lower payload allowing larger fuel capacity.

ACJ350
Airbus' corporate jet version of the A350, the ACJ350, is derived from the A350-900ULR. As a result of the increased fuel capacity from the -900ULR, the ACJ350 has a maximum range of 20000 km.

A350 Regional
In 2013, there were reports about an A350-900 variant for short haul market with MTOW reduced to around 250 t (from the standard 268 t) and engine thrust reduced to around 70000-75000 lb (from the standard 85000 lb). The variant, A350-900 Regional, was said to be optimized for routes up to 6800 nmi. Etihad Airways and Singapore Airlines were said to be ordering the A350 Regional. However, since 2013 there has been no further information or announcement about this variant.

A350-1000
The nearly 74-metre-long A350-1000 is the largest variant of the A350 family and is to seat 366 passengers in a typical three-class layout over 8000 nmi. With a 9-abreast configuration, it is designed to replace the Airbus A340-600 and compete with the Boeing 777-300ER and Boeing 777X. Airbus estimates a 366-seat -1000 should have a 35t lighter operating empty weight than a 398-seat 777X-9, a 15% lower trip cost and 7% lower seat cost with a 400 nm greater range. Compared to a 360-seats 777-300ER, Airbus claims a 25% fuel burn per seat advantage for a 369-seat A350-1000.

The 7 m extension seats 40 more with 40% more premium area. The A350-1000 has an 11-frame stretch over the −900 and will feature a slightly larger wing than the −800/900 models; a trailing-edge extension increasing its area by 4%. This will extend the high-lift devices and the ailerons, making the chord bigger by around 400 mm, optimising flap lift performance as well as cruise performance. The main landing gear is a 6-wheel bogie instead of a 4-wheel one, put in a one frame longer bay, and the Rolls-Royce Trent XWB engine thrust is augmented to 97,000 lbf. These and other engineering upgrades are necessary so that the −1000 model does not suffer a reduction in range.

Assembly of the first fuselage major components started in September 2015. In February 2016, final assembly started at the A350 Final Assembly Line in Toulouse; three flight test aircraft are being built and entry into service is scheduled for mid-2017. The first aircraft completed its body join on 15 April 2016. Its maiden flight took place on 24 November 2016. Its flight-test programme will be done in 1,600 hours: 600 hours on the first aircraft, MSN59, for the flight envelope, systems and powerplant checks; 500 hours on MSN71 for cold and warm campaigns, landing gear checks and high-altitude tests; and 500 hours on MSN65 for route proving and ETOPS assessment, with an interior layout for cabin development and certification. The first aircraft delivery is expected in October 2017 to Qatar Airways.

In 2011, Airbus redesigned the A350-1000 with higher weights and a more powerful engine variant for more range for transpacific operations to boost its appeal to Cathay Pacific, Singapore Airlines - which committed to 20 777-9 - and United Airlines - who could turn to 777-300ERs to replace its 747-400s ; but Emirates Airlines was disappointed with the changes and cancelled its order for 50 A350-900s and 20 A350-1000s instead of converting the whole order to the larger variant.

A350-800
The A350-800 was designed to seat 280 passengers in a three-class configuration with a 9-abreast seating, and have a range of 15200 km with an MTOW of 259 t and 337 kN thrust engines.

In January 2010 Airbus opted to develop the -800 as a shrink of the baseline -900, avoid a specific development and increasing its payload by 3 t or its range by 250 nmi but leading to a fuel burn penalty by "a couple of percent" according to John Leahy. The previously planned optimisation to the structure and landing gear was not beneficial enough against better commonality and maximum takeoff weight increase by 11t from 248t. The −800's fuselage is 10 frames shorter (six forward and four aft of wing) than the −900 aircraft. It was designed to supplement the Airbus A330-200 long-range twin. Airbus planned to decrease structural weight in the -800 as development continued, which should have been around airframe 20.

While its backlog reached 182 in mid-2008, it diminished since 2010 as customers switched to the larger -900. After launching the A330neo at the 2014 Farnborough air show, Airbus dropped the A350-800, with its CEO Fabrice Brégier saying "I believe all of our customers will either convert to the A350-900 or the A330neo". He later confirmed at a September 2014 press conference that development of the A350-800 had been "cancelled." There were 16 orders left for the -800 since Yemenia switched to the -900 and Hawaiian Airlines moved to the A330neo in December 2014: 8 for Aeroflot and 8 for Asiana Airlines, both also having orders for the -900. In January 2017, Aeroflot and Airbus announced the cancellation of its -800 order, leaving Asiana Airlines as the only customer for the variant.

Further stretch
Airbus is exploring the possibility of a further stretch offering 45 more seats. A 4 m stretch would stay within the exit limit of four door pairs, and a modest MTOW increase from 308 t to 319 t would need only 3% more thrust, within the Rolls-Royce Trent XWB-97 capabilities, and would allow a 7600 nmi range to compete with the Boeing 777-9 capabilities.

This variant is to be a replacement for the Boeing 747-400, tentatively dubbed the A350-8000, -2000 or -1100. Within the June 2016 Airbus Innovation Days, chief commercial officer John Leahy was concerned about the size of a 400-seat market besides the Boeing 747-8 and the Boeing 777X-9 and chief executive Fabrice Brégier feared such an aircraft could cannibalise demand for the -1000.

The potential 258 feet airplane is competing against an hypothetical 777-10X for Singapore Airlines.

Operators


There were 70 A350 aircraft in service with 11 operators.

Data at 28 February 2017