Boeing says successful high- and low-speed windtunnel tests have proved the Sonic Cruiser concept.
Dan Mooney, Boeing vice-president product development, says for competitive reasons the company had been reluctant to provide too much detail on how it could be confident about the transonic airliner's performance.
"Recent advances in technologies, such as computational fluid dynamics, have allowed us to do the iterations on the aircraft's aerodynamic configuration," he adds. "We can understand better the interaction of the elements of the design, such as engine nacelles and fins, and how to make the aircraft fly at Mach 0.98 without drag problems."
Mooney says: "Drag rise up to the Mach 0.98 cruise speed is very flat; and the aircraft's behaviour when it exceeds Mach 1 is remarkably stable." These were Boeing's two concerns with the concept before the windtunnel tests. The design is being refined, and Mooney says published images of the aircraft might deliberately not show the exact configuration.Informal talks continue with various airlines, including alliances such as Oneworld. Boeing hopes to be in a position in 12 months to move the project to "some sort of offerable status", although it would not be a launch in the traditional sense as it would be too early to make firm performance guarantees.
Mooney says the airline advisory group could become a formal "working together" team at about the same time to guide development of the aircraft. The Sonic Cruiser is due for service entry in 2008.
Source: Flight International
