Greg Gatlin, NASA aerospace research, inspects the truss-braced wing during testing in the Unitary Plan Wind Tunnel complex at NASA’s Ames Research Center.
NASA and Boeing are designing a longer, thinner, and lighter wing that requires a brace, or truss, to provide it with extra support. The lower-drag wing will reduce both fuel burn and carbon emissions by at least 50% over current-technology transport aircraft, and by 4 to 8% compared to equivalent advanced-technology conventional configurations with unbraced wings.

Engineers are using computer modeling of aerodynamics to iterate the design. They modify the dimensions and shape of the wing and truss to improve areas that may generate undesirable airflow that would increase drag and reduce lift. Then engineers test models in a wind tunnel using multiple experimental techniques to validate the computations and aircraft performance predictions.

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