Guy Norris/LOS ANGELES
BOEING'S PLANS to launch an ultra-long range version of the 777 for service entry by May 1999 are expected to be delayed by airline uncertainty over the derivative choice, and the emergence of new offerings from Airbus and McDonnell Douglas (MDC).
Boeing announced plans in June 1995 to launch the 17,725km (8,500nm) range, short-bodied 777-100X by the end of September on the back of airline requirements, primarily from American Airlines and Singapore Airlines (SIA). Interim studies of a 15,100km-range heavyweight version of the standard -200 model, the -200X, have now apparently divided interest in the study, with SIA favouring the smaller -100X, and American supporting the larger -200X.
Adding to the uncertainty is the appearance of new competition in the ultra-long-range market, with Airbus unveiling plans for a 310-passenger A340-500, and MDC actively working on a 305-passenger MD-XXLR. All have proposed entry-into-service dates of 2000/ 2001, which is well within the Boeing timescale.
Additionally, Boeing now believes that the -100X/-200X offerings are so diverse that they could serve different requirements. "I'd characterise it almost as two different marketplaces," comments 777-300 programme manager, Jeff Peace. "It's all the way from very long Pacific routes with 200 passengers to a design for more traditional 747-400 ranges at volume limit with the belly full."
Peace says that the maximum take-off weight (MTOW) limit of just under 300,000kg on the -100X is "not firm", and the -200X is still based around the 287,000kg limit of the -200IGW (increased gross weight). The May 1999 target is unlikely. "I would expect it could be later than that," he says.
Development of a possible heavier stretched -300, meanwhile, is not expected to help the case for the -200X. "The different body length changes the behavioural characteristics, although there are some synergies on the wing. But basically, they're two different design efforts," says Peace.
Boeing says that a high-gross-weight -300 with an MTOW of around 313,000kg has been part of "what-if" studies on the extended family, but says that no decisions have yet been made.
"The current aircraft would not be capable [of that weight] and we have no plans currently to increase the -300 capability," says John Monroe, 777-300 senior manager, programme management office. The aircraft structure is being designed for a maximum MTOW of just under 300,000kg.
Source: Flight International
