Boeing is formally proposing a revised, extended-range 747-400 design to several Asia-Pacific carriers as part of renewed efforts to launch the 747X family. The marketing campaign forms a critical part of Boeing's strategy to thwart Airbus Industrie's A3XX launch efforts in Asia.

The 747-400 derivative has been proposed to Cathay Pacific, Singapore Airlines (SIA) and Qantas. It is similar to the version proposed to the Australian carrier in 1998, which had a 413,140kg (910,000lb) maximum take-off weight (MTOW). The latest version, however, takes advantage of technological advances. Changes include the trailing edge wedge, blended winglets and 777-style cabin architecture and flightdeck.

The offer to SIA is understood to be for six aircraft, plus 10 options, with a similar number for Cathay Pacific. Qantas, which originally wanted to convert three late delivery aircraft to the original -400X offer, is thought to be interested in the heavy version for three remaining aircraft on option.

Boeing declines to confirm that firm offers have been made, but says its next -400X proposals "will capitalise on the -400, but with a new interior, flightdeck upgrades and other enhancements". The company adds that its strategic focus is returning to the 747X. "With the 777X launched, the 747 will be higher up on the chain".

The heavy 747 derivative, although grouped with the more extensive wing root insert and stretched 747X proposals, is likely to be called the 747-400ER and could be available in 2002.

In detail, it is expected to retain much of the original -400 increased gross weight (IGW) study. The derivative will offer an increased payload of almost 7,000kg, or alternatively, between 750km (400nm) and 800km extra range, giving the airlines the opportunity to develop new non-stop routes such as New York -Hong Kong, Los Angeles to Melbourne or New York Newark to Taipei. Extra fuel is carried in up to two auxiliary tanks, each holding 12,050 litres (3,180USgal), and located forward of the wing box where potable water is now stored.

General Electric and Pratt & Whitney are each offering 62,000lb-thrust (276kN) versions of the CF6-80C2 and PW4000 respectively, while Rolls-Royce is believed to be considering a 60,600lb-thrust RB211-524HT with a 5% throttle push in climb.

The heavier aircraft will incorporate the strengthened -400F outboard wing, as well as reinforcement throughout the aft part of the chord to take the trailing edge wedge and blended winglet.

Source: Flight International