Updating of Airbus's assumptions about cabin layout and typical internal equippage is behind an apparent recalculation of A350 baseline range and seating specifications contained in the airframer's publicity.
While the basic seat count on its foundation aircraft, the A350-900, remains largely unchanged at 315, the airframer is listing a shorter range figure of 7,750nm – down by 350nm on the previous 8,100nm.
Similarly the 350-seat figure for the A350-1000 has been revised upwards to 369 but the listed range is now 8,000nm rather than 8,400nm.
Airbus had been using the higher range figures, which also appeared on its website data about the aircraft, in press material including that accompanying the recent Japan Airlines order for the -900 and -1000.
But while the change appears recent, the airframer has been using amended specifications for some time, and the amendments are unconnected to flight-test performance data.
Airbus explains that it updated its assumptions on the way airlines are configuring their aircraft - notably with two-class cabins rather than three - as well as seat pitches and weights, in-flight entertainment, catering items and other equipment.
It says that these assumptions, which had remained unchanged for years, no longer reflected typical airline operations. "It's probably a good idea to show something closer to the real world," it says.
“Now we have customers with real layouts under way, we’ve adapted to what they’re doing with the [aircraft]."
While the update provided for more passengers in baseline accommodations it also took account of additional non-structural weight.
Accommodation on the A350-800, the smallest variant, is given as 276 seats, an extra six, while its range is listed as 8,250nm compared with the earlier figure of 8,500nm.