Airbus has finalised some significant design decisions on the exterior look and structural make-up of its A350 XWB in recent months, but the cockpit has also undergone a major rethink with the decision to abandon any links with the A380 in favour of an all-new configuration that rivals the Boeing 787.
Until now, Airbus had planned to equip the XWB had with a cockpit based on that of the A380. "After discussions with customers, we've decided to go away from the A380-sized cockpit displays and adopt larger displays," says A350 XWB chief engineer Gordon McConnell.
The XWB flightdeck has now six identical rectangular horizontal screens measuring 15in (38cm) diagonally across. The new configuration has two central displays mounted one above the other (the lower one on the centre console in front of the thrust levers), and a single primary flight/navigation display in front of each pilot with an on-board information system screen adjacent to it.
By comparison, the A380's flightdeck incorporates an eight-screen layout on the main instrument panel (rectangular upright displays) plus two larger rectangular on-board information screens each mounted at each side of the main panel.
McConnell says that there were two main drivers behind the decision to revamp the cockpit: "The ability to share some of this airport and navigation information on the centre display is seen as advantage for the pilots because it means they can be looking at the same display together."
A350 XWB specification A350-800 A350-900 A350-1000
Maximum take-off weight (t) 245 265 295
Maximum landing weight (t) 182.5 202.5 225.5
Maximum zero fuel weight (t) 171 189.5 211
Fuel capacity (l) 129,000 138,000 156,000
Powerplant 2 x 74,000lb 2 x 83,000lb 2 x 92,000lb
Trent XWB-74 Trent XWB-83 Trent XWB-92
Two-class seating (breakdown) 276 (36/240) 315 (48/267) 369 (54/315)
Cabin diameter (m) * 5.97 5.97 5.97
Service entry Mid-2014 Mid-2013 Late 2015
* - Maximum outer diameter Source: Airbus
Secondly, it gives Airbus "some future proofing" he says. "It allows us to put some more advances in navigation technology on to the displays in the future."
The revised flightdeck retains traditional Airbus switching and features such as the non-back-driven thrust levers (when autothrust is engaged) and the A380's curser-control device and "QWERTY" pedestal-mounted keypad. However, the larger screens are similar to the Rockwell Collins displays that equip the 787's flightdeck.
Airbus declines to comment on who is competing to provide the A350's flightdeck avionics, but Flight International understands that the incumbent A380 supplier Thales is vying with Rockwell for the deal. A decision is expected soon.
The A350 nose section's new revised outer shape incorporates a flightcrew escape hatch for the first time on an Airbus aircraft, as the side windows are fixed and not openable.
McConnell says with the revisions made to the nose fuselage, the concept is now well advanced and is unlikely to undergo any more major changes. "We've changed the shape of the upper radius and upper shell of the fuselage for aerodynamic reasons. We've refined the windscreen and worked to minimise the centre post to improve the pilots' visibility."
The whole cockpit canopy section has aluminium alloy skin panels, which McConnell says offers "the best solution in terms of the overall balance between weight/cost/manufacturing process etc".
Airbus has frozen the static thrust levels for the three A350 variants for entry-into-service at ratings lower than previously expected. The thrust levels provided to Rolls-Royce for its Trent XWB engine are 74,000lb (329kN), 83,000lb and 92,000lb for the A350-800, -900 and -1000, respectively. These are 1,000 to 4,000lb lower than previous estimates, says McConnell. "After windtunnel and development work on low-speed performance, we've improved our level of prediction and believe we have better performance than anticipated at the start of the programme."
With the A350's double-lobe cabin cross-section finalised (at around 5.97m (235in) outer diameter), Airbus has built a portable cabin mock-up which it recently displayed at September's customer focus group meeting in Bordeaux. Equipped with fairly basic furnishings and eight- and nine-abreast economy seating, the mock-up is designed to enable customers to make direct comparisons with the 787, rather than to articulate concepts as previous Airbus mock-ups have, says Robert Lange, head of aircraft interiors marketing. "It is designed to allow customers to come along with the tape measures and understand exactly what they can fit in the XWB's cabin.
Read our recent in-depth report on the new twinjet at www.flightglobal.com/a350xwb
Source: Flight International