PAUL LEWIS / WASHINGTON DC & GUY NORRIS / LOS ANGELES
Boeing claims higher take-off weight gives derivative 920km more range than A340-500
Boeing has restarted development of the 777-200LR and increased the design's maximum take-off weight (MTOW) to provide more range in a bid to challenge the Airbus A340-500, with eyes on a possible Singapore Airlines (SIA) requirement.
Work on the 777-200LR was suspended in October 2001 because of market uncertainty, by which time around 10% of the design drawings had been released.
Development of the more popular 777-300ER stretch derivative has continued and as a result of design commonality has produced another 20-30% of the drawings for the -200LR, according to Lars Andersen, Boeing 777 long-range programme manager.
Boeing has extended the -200LR's maximum range from the previously billed 16,330km (8,830nm), to 16,970km as a result of "airlines pushing for more capability", says Boeing, which now claims a 920km range advantage over the A340-500. The MTOW of the aircraft has been raised from 340,500kg (750,000lb) to 347,760kg with no structural changes, giving airlines the option to trade fuel for additional payload over shorter distances.
The 7,260kg gross weight increase, which is within current structural performance and engine thrust limits, is achieved by using the "12% to 14% travel of the cg [centre of gravity] location. At the same operating weight, you can load it in a specific way in terms of passengers, cargo and fuel and can take-off at 766,000lb," says Andersen.
Among the more demanding year-round routes identified by Boeing are Singapore-Los Angeles, Hong Kong-New York, and Sydney-Dallas. SIA ordered the A340-500 when the then-proposed 777-X was a shorter-range aircraft and there were concerns about extended-range twin-engine operations (ETOPS).
The revised -200LR effectively brings the aircraft within SIA's original specifications for a 206-seat aircraft with a still-air range of 16,280km, plus fuel reserves. Boeing adds that the -200LR will be cleared for 207min ETOPS on entry into service in January 2006 providing better route flexibility across the Pacific than the current 180min.
Boeing has been trying for some time to overturn SIA's order for five A340-500s, the first of which is due to enter service in October. Boeing is again believed to be pushing the aircraft, as SIA looks at the 777-300ER and A340-600 as a 747-400 replacement.
Launch operator Pakistan Airlines has ordered two -200LRs and EVA three, with proposals for 11 more aircraft being pursued.
Source: Flight International
