A patent drawing filed by Boeing in early 2001 put the baseline aircraft's dimensions at approximately 250 feet (76 m) in length, with a wingspan of 164.9 feet (50.3 m).[9] With a delta wing and canards arrangement, and flying just short of the speed of sound at Mach 0.95-0.98 (about 650 mph (1,050 km/h) at altitude), the Sonic Cruiser promised 15-20% faster speed than conventional airliners without the noise pollution caused by the sonic boom from supersonic travel. As an example, a flight using the Sonic Cruiser from London to Singapore was expected to be two hours shorter than one using a conventional airliner.[2] In addition, the landing and takeoff noise was expected to meet Stage 4 requirements.[18] The aircraft was designed to fly at altitudes in excess of 40,000 ft (12,000 m) to avoid existing air traffic,[2] with a range between 6,000 and 10,000 nautical miles (11,000 and 19,000 km).[8] Boeing estimated the Sonic Cruiser's fuel efficiency would be comparable to best performing twin-engine wide body airliners in 2002 on a per-passenger basis.[8][19]