Tuesday, December 22, 2009

Airbus A 350

The Airbus A350 is a long-range, mid-size, wide-body family of airliners currently under development by European manufacturing group Airbus. The A350 will be the first Airbus with both fuselage and wing structures made primarily of carbon fiber-reinforced plastic.[2] The A350 is designed to compete with the Boeing 777 and the Boeing 787. Airbus claims that it will be more fuel-efficient, with up to 8% lower operating cost than the Boeing 787.[2][3] It is scheduled to enter into airline service in 2013. The launch customer for the Airbus A350 is Qatar Airways, which ordered the -900 variant.


Early designs

When Boeing announced its 787 Dreamliner project, it claimed the lower operating costs of this airplane would make it a serious threat to the Airbus A330. In public announcements, Airbus initially rejected this claim, stating that the 787 was itself just a reaction to the A330, and that no response was needed to the 787.

The airlines pushed Airbus to provide a competitor, as Boeing had committed the 787 to have 20% lower fuel consumption than the Boeing 767. At first, Airbus proposed a simple derivative of the A330, unofficially dubbed the 'A330-200Lite', with

improved aerodynamics and engines similar to those on the 787. The airlines were not satisfied, and Airbus committed €4 billion to a new design to be called the A350. 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 stabilizer 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 16 September 2004, then-Airbus president and CEO Noël Forgeard confirmed that a new project was under consideration, but did not give a proje

ct name, and would not state whether it would be an entirely new design or a modification of an existing product. Forgeard indicated that Airbus would finalise its concept by the end of 2004, begin consulting with airlines in early 2005, and aim to launch the new development programme at the end of that year. 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.[5]

On 6 October 2005, full industrial launch of the program was announced with an estimated development cost of around € 3.5 billion. This version of

the A350 was planned to be a 250– to 300-seat twin-engine wide-body aircraft derived from the design of the existing A330. Under this plan, the A350 would have modified wings and new engines, while sharing the same fuselage cross-section as its predecessor. As a result of a controversial design, the fuselage was to consist primarily of Al-Li, rather than the CFRP fuselage on the 787. It was to see entry into service in 2010 in two versions: the A350-800 capable of flying 8,800 nmi (16,300 km) with typical

passenger capacity of 253 in 3-class configuration and the 300-seat (3-class) A350-900 with 7,500 nmi (13,900 km) range. It was designed to be a direct competitor to the 787-9, and 777-200ER.

Almost immediately, Airbus faced criticism on the A350 project by the heads of two of its largest customers, ILFC and GECAS. On 28 March 2006, in the presence of hundreds of top airline executives, Steven F. Udvar-Hazy, of ILFC lambasted Airbus' strategy in bringing to market what they saw as "a Band-aid reaction to the 787," a sentiment that was echoed by GECAS president Henry Hubschman. Udvar-Hazy called on Airbus to bring a clean-sheet design to the table, or risk losing most of the market to Boeing.[6][7]

Several days later, similar comments were made by Chew Choon Seng, CEO of Singapore Airlines. Chew stated, "having gone to the trouble of designing a new wing, tail, cockpit" and adding advanced new materials, Airbus "should have gone the whole hog and designed a new fuselage."[8] At the time, Singapore was reviewing bids for the 787 and A350.

Airbus responded by stating it was considering improvements for the A350 to satisfy customer demands.[9] At the same time, Airbus then-CEO Gustav Humbert suggested that there would be no quick fixes, stating, "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."[10]

On 14 June 2006, Singapore Airlines announced it had selected the 787 over the A350, ordering 20 787-9s.[11] Emirates Airline decided against making an order for the initial version of the A350 because of weaknesses in the design,[12] but has sin

ce made a large order for A350s


As a result of these criticisms, in mid-2006 Airbus undertook a major review of the A350 concept. The proposed new A350 with a larger fuselage cross-section has become more of a competitor to the larger Boeing 777 as well as some models of the Boeing 787. The A350 fuselage can accommodate 10 passengers per row in a high-density configuration.[14] The A330 and previous iterations of the A350 would only be able to accommodate 8 passengers per row in normal configurations. The 787 can accommodate 8 or 9 pass

engers per row, while the 777 can accommodate 9 passengers per row (a few airlines seat 10 passengers abreast in some of their 777s). From the point of view of a seated passenger, the A350 cabin is 13 cm (5.1 in) wider at eye level than the competing Boeing 787, and 28 cm (11 in) narrower than the Boeing 777, its other competitor. (See wide-body aircraft for a comparison of cabin widths and seating). All A350 passenger models will have a range of at least 8,000 nmi (15,000 km).

There was some speculation that the revised aircraft would be called the Airbus A370 or A280, with Airbus going as far as accidentally publishing an adve

rt referring to the aircraft as the "A280" on the Financial Times website. However, on 17 July 2006, at the Farnborough Airshow, Airbus announced that the redesigned aircraft would be called A350 XWB (Xtra-Wide-Body).

Airbus achieved its first sale of the redesigned A350 four days after its unveiling when Singapore Airlines announced an order for 20 A350 XWBs with options of a further 20. Its CEO, Chew Choon Seng, said in a statement, that "it is heartening that Airbus has listened to customer airlines and has come up with a totally new design for t

he A350."[15]

Late in 2006, a decision on formal launch was delayed as a result of delays of the Airbus A380[16] and wrangles about how the development would be funded. EADS CEO Thomas Enders stated that the A350 program was not a certainty, citing EADS/Airbus' stretched resources.[17][18] On 1 December 2006 the EADS board agreed the industrial launch of the sixth iteration of the A350 [19] with costs mainly borne out of cash-flow. First delivery for the -900 is scheduled for mid-2013, with the -800 and

-1000 following on, respectively, 12 and 24 months later.[20] At a press conference 4 December 2006 a few new technical details of the A350 XWB design were revealed, but no new customers were identified and John Leahy indicated existing A350 contracts were under re-negotiation due to increases in prices compared to the original A350s contracted.

On 4 January 2007, Airbus announced that Pegas

us Aviation Finance Company had placed the first firm order for the A350 XWB with an order for two aircraft, though the variants were unspecified at the time.[21]

The Airbus board of directors approved the industrial launch of the A350-800, -900 and -1000 in December 2006. The XWB will impose a couple of years of delay into the original timetable and almost double development costs from $5.3 billion to approximately $10 billion.[22][23]


In September 2007, Airbus rolled out new design ad

vances to a gathering of 100 representatives from existing and potential XWB customers. The A350 XWB will be built on the technologies developed for Airbus A380 and will have a similar cockpit and fly-by-wire systems layout.[24] The A350XWB will be made out of 53% composites, 19% Al/Al-Li, 14% titanium, 6% steel and 8% miscellaneous.[25] This compares to the Boeing 787, which consists of 50% composites, 20% aluminium, 15% titanium, 10% steel and 5% the balance.[26] October 2008 was the Airbus internal goal to freeze the design and Airbus expects 10% lower airframe maintenance cost and 14% lower empty seat weight than competing aircraft.[2]

Airbus claims that the new design provides a better cabin atmosphere with 20% humidity level during flight and typical cabin altitude at or below 6,000 ft (1,800 m), pressurization at 6,000 ft (1,800 m) and flow management system that adapts cabin airflow to passenger load with draft-free air circulation.[2] Airbus is aiming to certificate the A350 with 350min ETOPS capability upon service entry


The new XWB fuselage will have 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 will have a maximum outer diameter of 5.97 m (19.6 ft), compared to 5.64 m (18.5 ft) for the A330/A340. The cabin's internal diameter will be 5.61 m (18.4 ft) wide at armrest level compared with 5.49 m (18.0 ft) of the 787[28] and 5.86 m (

19.2 ft) of the 777).

In the eight-abreast 2-4-2 arrangement, which is a premium economy layout, the seats will be 49.5 cm (19.5 in) wide between 5 cm (2.0 in) wide arm rests. Airbus claims that the seat width will be 1.3 cm (0.5 in) greater than the seat on the 787 in the equivalent configuration. In the 9-abreast, 3-3-3 standard layout, the XWB's seat width will be 45 cm (18 in) which will be 1.3 cm (0.5 in) wider than the proposed equivalent seat layout for the Boeing 787.[2][28] A 10-abreast high density is also available.[14]

Although Airbus previously suggested Boeing's use of composite materials for the 787 fuselage was premature, and that the original A350s would be made from aluminium-lithium, the new A350 XWB will feature large carbon fibre panels for the main fuselage skin. After facing criticism for maintenance costs,[29] Airbus confirmed in early September 2007 the adoption of composite fuselage frames for the aircraft structure.[30][31] The composite frames will feature aluminium strips to ensure the electrical continuity of the fuselage (for dissipating lightning strikes).[32] However, the fuselage crossbeams remain metallic, but Airbus is running trade-off studies to evaluate switching them to composite.[citation needed]

Airbus had signed a firm contract with BMW for development

of an interior concept for the original A350.[33]


The A350 will feature new all-composite wings that will be common to all three proposed variants.[34] With an area of 443 m2 (4,770 sq ft)[35] it will be

the largest wing ever produced for a single-deck widebody aircraft. The geometric wingspan of 64.8 m (213 ft)[35] is 4.5 m (15 ft) greater than that of the A330. This is the same span as the long-range Boeing 777-200LR/777-300ER, which has slightly less area. The new wing will have 31.9-degree sweep[35] (1.9 degrees more than the A330) helping to increase typical cruise speed to Mach 0.85 and maximum operating speed to Mach 0.89.

A new trailing-edge high-lift system has been adopted with an advanced dropped-hinge flap (similar to that of the A380), which permits the gap between the trailing edge and the flap to be closed with the spoiler.[36] The manufacturer has extensively used com

putational fluid dynamics and also carried out more than 4,000h hours of low- and high-speed windtunnel testing to refine the aerodynamic design[37], achieving the final configuration of wing and winglet on the "Maturity Gate 5" on 17 December 2008.[38]

Airbus is planning a £570 million (US$760 million) investment to up

grade composite capability at its Broughton site in the United Kingdom, in preparation for its role as final assembly location for the A350 XWB wing.[39] In June 2009, the Welsh Assembly announced provision of a £28million grant to provide a training centre, production jobs and money towards the new production centre.[40]


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.

[41] 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 center post. The upper shell radius of the nose section has been increased. The nose bears a striking resemblance to the nose of the BAe 146.

The nose is likely to be constructed from aluminium but Ai

rbus is currently running trade-off studies considering 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.[42]


The revised design of the cockpit dropped the A380-sized dis

play and adopted 15 in (38 cm) LCD displays. The new six-screen configuration will have two central displays mounted one above other (the lower one above the thrust levers) and a single (for each pilot) primary flight/navigation display with an on-board information system screen adjacent to it.[43] Airbus claims the new cockpit will allow advances in navigation technology to be placed on the displays in the future plus flexibility and capacity to upload new software and to combine data from multiple sources and sensors for flight management and aircraft systems control.[44] The A350 XWB will also feature a head-up display.

The avionics will be a further development of the inte

grated 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 landing gear, fuel, brakes, pneumatics, oxygen system, cabin pressurisation system, and fire detection.[44] Airbus claims benefits such as reduced maintenance and less weight because 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 avionics full-duplex (AFDX) standard, already employed in the A380 instead of the Arinc 429 syste

m on the A330/A340.

In January 2008, French-based Thales Group won the US$2.9 billion 20-year contract to supply avionics and navigation equipment for the A350 XWB. Thales competed against Honeywell and Rockwell Collins for the flight deck supply contract.[45] However, US-based Rockwell Collins and Moog Inc were chosen to supply the horizontal stabiliser actuator and primary flight control actuation, respectively.


Airbus has confirmed that it will retain a full bleed ai

r system on the engines,[46][47] rather than the bleedless configuration used on the Boeing 787. Rolls-Royce has agreed with Airbus to supply a new variant of the Trent engine for the A350 XWB, currently called the Trent XWB. After the low-speed windtunnel test, Airbus has frozen the static thrust at sea level for all three proposed variants in the 74,000–92,000 lbf (330–410 kN) range.

GE has stated it will 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.[48] Fellow Engine Alliance partner Pratt & Whitney seems to be at odds with GE on t

his, publicly stating that it is looking at an advanced derivative of the GP7000.[49] In April 2007, Airbus former chief executive Louis Gallois held face-to-face talks with senior General Electric management over developing a new variant of the GEnx engine for the A350 XWB.[50]

In June 2007, Rolls-Royce announced that it had signed its biggest ever contract with Qatar Airways for the Trent XWB to power 80 A350 XWBs on order from Airbus worth $5.6 billion at list prices,[51] and in June 2007, Airbus' Chief Operating Officer John Leahy indicated that the A350 XWB will not feature the GEnx engine, claiming that Airbus wants GE to offer a more efficient version for the new Airbus airliner.[52] Sin

ce then, largest GE engines operators Emirates Airline, US-based US Airways, Hawaiian Airlines and ILFC have selected the RR Trent XWB for their future fleet of A350.

The Trent XWB will feature a 3-meter (118 inch) fan diameter and the design will be based on the advanced developments of the Trent 900 (Airbus A380) and Trent 1000 (Boeing 787). The Trent XWB may also benefit from the next-generation reduced acoustic mode scattering engine duct system (RAMSES), which is a noise-dampening engine nacelle intake and a carry-on design of the Airbus's "zero splice" intake liner developed for the A380.[53] Engine thrust-reversers and nacelles will be supplied by US-based Goodrich


Auxiliary power unit and air management system

The A350 XWB will feature a 1,700 shp (1,300 kW) HGT1700 auxiliary power unit by Honeywell, which has 10% greater power density than the previous generation of Honeywell's 331 APU family. Honeywell will also supply the air m

anagement system: the bleed air, environmental control, cabin pressure control and supplemental cooling systems.[54] The ram-air turbine will be in the lower surface of the fuselage, and the generator requirement is 100 kVA compared to 150 kVA for the A380. The selection of US-based Honeywell to supply this system is part of Airbus' strategy to contract complete work packages to a smaller number of major suppliers who are becoming system integrators on the programme.[55]

Fuel and hydraulic systems

US-based Parker Hannifin has been selected to supply

the complete fuel package: inerting system, fuel measurement and management systems, mechanical equipment and fuel pumps. The fuel tank inerting system will feature air-separation modules to generate nitrogen-enriched air that will be used to reduce the flammability of fuel vapour in the tanks.

Parker will also provide 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 co

ntracts will generate more than US$2 billion in revenues over the life of the programme.[56]

Landing gear

Airbus adopted a new philosophy for the attachment of the A350’s main landing gear as part of the switch to a composite wing structure. Each main landing gear 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.[57]

Airbus devised a three-pronged main landing gear 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 (13 ft) long bay. The proposed higher weight variant, the A350-1000 (and the A350-900R, which is being proposed to British Airways, with -900 size but with sufficient fuel capacity to allow nonstop London-Sydney flights) will use a six-wheel bogey, with a 4.7 m (15 ft) landing gear bay.[58] French-based Messier-Dowty will provide the main landing gear. The nose gear will be supplied by Li



There are three variants of the A350 and all launched in 2006. The A350-900 is scheduled to enter service in 2013. The A350-800 is scheduled to e

nter service in 2014. The A350-1000 is scheduled to enter service in 2015.[60] All variants will be offered as corporate jets by wholly-owned subsidiary Airbus Executive and Private Aviation.


The A350-800 will seat 270 passengers in a 3-class cabin 9-abreast layout and will have a range of 8,300 nmi (15,400 km).[35] It is designed to compete with the Boeing 787-9 and to directly replace the Airbus A330-200.


The A350-900 is the first model scheduled to enter service (EIS) in 2013 and seats 314 passengers in a 3-class cabin 9-abreast layout. It will have a range of 8,100 nmi (15,000 km). Airbus claim that the A350-900 will have a decrease of 16% MWE per seat, a 30% decrease in block fuel per seat and 25% better cash operating cost against the Boeing 777-200ER. The -900R and -900F variants also have been proposed but not yet launched. These will feature the higher engine thrust, strengthened structure and landing gear of the -1000. The -900 is designed to compete with the Boeing 777-200ER and r

eplace the A340-300.


The A350-1000 is scheduled to enter service in 2015. It is the largest variant of the A350 family and will seat 350 passengers in a 3-class cabin 9

-abreast layout. It will have range of 8,000 nmi (14,800 km). It is designed to compete with the Boeing 777-300ER and replace the A340-600.

Ini Cockpit Airbus A350

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