The success of the initial flight demonstrations of the Advanced Composite Cargo Aircraft (ACCA) prompted the U.S. Air Force late last year to officially designate the ACCA as the X-55A. In June 2009, the Air Force Research Laboratory and Lockheed Martin completed the first flight demonstration of the X-55A, establishing basic handling qualities and monitoring structural performance and response to load maneuvering—assessments relying on a network of approximately 600 sensors (strain gauges and accelerometers) integrated within the airframe. Subsequent flights occurred in July and August and were geared toward expanding the maneuvering envelope and recording external aerodynamic flow visualization. As a critical-technology experiment, the ACCA program demonstrated the feasibility of designing and manufacturing large, bonded, unitized structures featuring low-temperature, out-of-autoclave curing. To read more about its development, visit www.sae.org/mags/aem/2907.