Boeing [NYSE:BA] has built a 20-foot (6-meters) long composite fuselage section to test candidate materials and manufacturing techniques for the Sonic Cruiser. Other materials and techniques also are being considered. Shown here, the section is readied for Boeing's large anechoic chamber to test the acoustic characteristics. Other tests will determine durability and maintainability. Although the test section has a 14-foot (4.3-meters) cross-section, the Sonic Cruiser's final dimensions have not been set. Fuselage cross-section is considered one of the crucial decisions in a new design and generally is made late in the design cycle after substantial customer input.