Andrzej Jeziorski/HAMBURG

LUFTHANSA operations chief executive Klaus Nittinger has criticised recent changes in Boeing's design proposals for its 747-500/600X.

"The aircraft has changed so drastically [since November] that it has moved far away from what we would like to see," says Nittinger. Lufthansa was enthusiastic about the initial proposal for the -600X, which was to have a high degree of commonality with the 747-400s already in the airline's fleet. Current design no longer offers this advantage, says Nittinger.

He adds that the change has now opened the field for competing proposals, such as that for the Airbus A3XX.

The aircraft Boeing was proposing in 1995 was to have about 25% more capacity than that of the -400, with the same type rating, cruise speed, and as much system commonality as possible. The landing gear was to be a reinforced version of the -400 undercarriage.

The range requirement was that the aircraft should be capable of being operated between Europe and Singapore, and a target was set that seat-kilometre costs should be at least 10% lower than in the -400.

The aircraft was sized to fit inside an 80m (260ft) square box, and would have been powered by existing engines, while still being no noisier than the 747-400.

This noise requirement restricted the maximum take-off weight of the aircraft, according to Nittinger.

Instead, the current design has a new cockpit with fly-by-wire technology, new engines - either the Rolls-Royce Trent 900 or the General Electric - Pratt & Whitney Engine Alliance power plant - and new landing gear. The type-rating commonality has been lost, and the new technology has driven the cost of the aircraft up. Boeing was therefore, forced to increase the seating capacity, to keep seat-kilometre costs down.

The -600X version now has a $230 million price tag (compared with the expected $200 million), which has caused many potential customers to waver.

The increased seating capacity means that the aircraft now has an 85m-long fuselage, exceeding the original size target.

"People really have to study this very carefully," says Nittinger, explaining that preliminary studies indicate that an aircraft of this size, could reduce throughput at busy airports such as Heathrow, because of its parking space requirement, as well as the need for special taxi procedures and increased separation, from following aircraft in the approach.

Nittinger says that he has told Boeing that its design approach, favouring 777 operators, could end up losing the company customers. "Even those who were pushing for a bigger solution would still have bought [a smaller aircraft with] greater commonality with the -400," he says.

Lufthansa must now consider whether it still wants a larger aircraft, or whether it will order additional 747-400s.

The airline could still order about six aircraft in the 747-600X or A3XX class, for its busiest routes to Bangkok and New York.

In response to the criticism, Boeing says: "We hope to work through Lufthansa's concerns, much like we are working through the concerns raised by other customers and are trying to work with all of them to configure an aircraft that will best meet the needs of each airline."

Source: Flight International