Boeing's second X-48B air vehicle has been modified into the X-48C for research for NASA's Environmentally Responsible Aviation, or ERA, project.
Modifications include removal of the aircraft's winglets and the addition of twin vertical tails. Two larger fanjet engines will replace the original three micro-turbojets, and an extended deck area was added underneath and extending aft of the new engines. The modifications are intended to explore their potential for reducing noise from the X-48C configuration, and planned future flight tests will primarily contribute noise-shielding data to NASA's ERA project database.
The C-model arrived at NASA's Dryden Flight Research Center in October 2009 following testing in NASA Langley Research Center's full-scale wind tunnel for aircraft stability and control checkout following the modifications.