Boeing has increased the maximum takeoff weight (MTOW) of its 747-8 Intercontinental and 747-8 freighter after its flight loads survey revealed additional structural margin available to customers.
According to its latest airport planning document, Boeing has increased the aircraft's MTOW to 448t (987,000lb), an increase of 6t (13,000lb) from 442t (975,000lb).
Early freighter deliveries, said Boeing, have been certified at 442t MTOW and, after April, deliveries will reflect the expanded 448t MTOW. A service bulletin to operators expected at the same time will approve the 442t MTOW aircraft for operation at 448t, the airframer said.
Boeing completed 747-8F and Intercontinental certification flight testing in August and October, respectively.
While Boeing said the move is not aimed specifically at regaining payload and range capability after a growth in structural weight during development, the programme has faced cancellations due to a performance shortfall of early freighters.
Atlas Air Worldwide Holdings cancelled three 747-8F aircraft in September 2011 after "lengthy delays and performance considerations."
Additionally, Boeing's December 2011 update to its 747-8 and -8F airport planning document included references to the aircraft's operating empty weight (OEW) and max structural payload.
The document listed the maximum structural payload for the passenger configured model as 82.1t (181,000lb) and the pre-service bulletin for the 747-8F at 134t (295,200lb), which increased after April's update to 139t (306,000lb).
Further, the OEW of the freighter model was set to transition from 191.3t to 190.9t (421,800lb to 421,000lb), a reduction of 363kgs (800lb), while the passenger model was listed at 213t (470,000lb).
The figures were later listed as "TBD" or to be determined and Boeing said the removal was due to a further review of its catalog weights and ranges for the 747-8 family.
Boeing delivered a total of nine 747-8F aircraft in 2011, and is readying to deliver its first 747-8 to a completion centre for outfitting for a VIP customer in February, followed by airline launch customer Lufthansa in March, said programme sources.