Boeing plans for revolutionary high-speed airliner in doubt

Boeing yesterday cast doubt on whether it would go ahead with plans to build a revolutionary new commercial airliner capable of travelling at just below the speed of sound and flying non-stop from London to Sydney in three-quarters of the current time.

The Sonic Cruiser was unveiled to an astonished aviation industry just over a year ago in an attempt by the Seattle-based aircraft manufacturer to upstage the launch of the Airbus A380 super jumbo.

Powered by new engines and built largely with composite materials, the Sonic Cruiser would seat 200 to 250 passengers and would be capable of reaching Sydney in 17 hours and New York in six hours. Boeing has spent the last year testing out its design with a dozen of the world's leading airlines, including British Airways and Virgin Atlantic.

But a senior Boeing executive disclosed yesterday that there was no agreement among customers about what sort of aircraft was wanted and he hinted that the US manufacturer could scale back its plans radically.

He also revealed that the Sonic Cruiser team in the US was now working on a range of alternative aircraft which could include an updated version of a conventional 250-seat jet to replace the ageing 767 model.

Toby Bright, executive vice-president of Boeing for commercial airplane sales, said: "We won't do this aeroplane unless it makes sense for us and sense for our customers. We have been working hard with customers all year, listening to them and asking what aircraft works for you but there is not a consensus yet of what is wanted."

He added: "We are always working on other products and we have had the Sonic Cruiser team looking at an array of possibilities." Should Boeing scrap or scale back plans for the Sonic Cruiser, it would be a major victory for Airbus which has consistently argued that the future market is for super jumbos operating between hub airports such as Heathrow, Tokyo and New York. The A380 will carry 555 passengers in a three-class configuration but could be adapted to hold as many as 650 passengers.

Critics of the Sonic Cruiser have also argued that its increased fuel burn and noise would make it environmentally unacceptable. But Boeing maintains the aircraft would be as fuel efficient per passenger mile as existing jets and quieter than the current 747.

Nevertheless, Mr Bright admitted that since Boeing had unveiled the Sonic Cruiser in March last year, the airline industry had been hit by the biggest downturn in its history following 11 September. This had diverted the attention of many airlines from ordering new planes, let alone thinking about the need for a near-supersonic jet.

But he said that interest had now begun to recover and Boeing hoped to give a clearer indication about the future of the Sonic Cruiser this autumn. The original Boeing plan was to bring the new jet into service in late 2007 or early 2008.

Industry observers believe that what Boeing is likely to do now is proceed with the development of a more conventional aircraft which incorporates some of the technologies that would have gone into the Sonic Cruiser.

Boeing has resolutely refused to put a price tag on the aircraft or provide indications of the size of the potential market or the overall development costs. But it continues to argue that demand for the super jumbo-sized jets will be fewer than 400 compared with the Airbus estimate of 1,300 to 1,400.

Boeing's latest long-range market forecast will be published next month in advance of the Farnborough air show at which it is tipped to announce an order for more than 100 737 aircraft from the no-frills airline easyJet.