Moments and Milestones: Boeing Unveils “Sonic Cruiser”

Farther, faster, and quieter—as opposed to bigger—are the capabilities that the Boeing Company says it is seeking in the next generation of airliners.

Amid speculation as to where the company is going with product development, President Alan Mulally recently announced that his design team is focusing on a “sonic cruiser” that could operate above 40,000 feet at Mach .95 or greater over a range of 10,350 miles.

On the surface, such claims are outside the range for existing technology, given the aerodynamic problems an aircraft encounters as it approaches Mach speeds. The fully loaded Concorde, for example, can routinely operate at Mach .95, but only over ranges of roughly 3,200 miles. Vice President for Business Strategy and Development Michael Bair says Boeing is gearing up to address the technical issues inherent in the new design and sees “a very high probability” that the program will go forward. The company estimates that the aircraft could enter service between 2006 and 2008.

The new airplane would be a radical departure from Boeing’s “derivatives” philosophy—stretching or otherwise redesigning its 747, 767, and 777 products. In particular, the company says it is backing off from concentration on a 747X aircraft that could compete in the market for high-capacity transports (500 to 600 passengers). Instead, the sonic cruiser would target an altogether different category, seating 225 passengers, although some airlines are asking Boeing to consider a version carrying 250 to 300 passengers.

The sonic cruiser has canards and double-delta wings supporting twin engines. Responding to observations that the aircraft is suggestive of stealth technology, Boeing acknowledges that the design borrows from military craft—the XB-70 comes to mind.

The speed of the transport would cut transatlantic flight times by at least two hours, and trans-Pacific flights three hours, reducing operating costs and creating more revenue opportunities for operators. The airlines are likely to place the aircraft in service to city pairs that make the best use of its speed, and some routes currently unserved could open up as a result of the new math.

By building a quieter long-range airplane, Boeing also hopes to give carriers a way to get around curfews and to schedule routes for speed. Carriers flying long distances face the dilemma of scheduling takeoffs and landings within noise restrictions at widely separated points. What is acceptable upon takeoff may be wholly unacceptable upon landing. The low-noise profile of the new airplane would partly derive from a high climb rate and a high thrust-to-weight ratio.

—Stuart Nixon