Smaaart task order: statement of work (SOW.) task title: HWB multi BAY test article analysis and assembly 1.0 introduction/background: NASA created the environmentally responsible aviation (ERA)…

Smaaart task order: statement of work (SOW.) task title: HWB multi BAY test article analysis and assembly 1.0 introduction/background: NASA created the environmentally responsible aviation (ERA) project to explore and document the feasibility, benefits, and technical risk of vehicle concepts and enabling technologies that will reduce the impact of aviation on the environment. Today's current generation of aircraft has benefitted from NASA investments in aeronautical research that have improved fuel efficiencies, lowered noise levels, and lessened harmful emissions. Although substantial progress has been made, much more needs to be done. The nation's air transportation system will expand by a factor of two or three within the next two decades, potentially increasing aviation's contribution to climate change. The ERA project works to reduce the environmental harm that could result from such an expansion. Among the technologies to be explored in the ERA project are the following: unconventional aircraft configurations that have higher lift to drag ratio, reduced drag and reduced community noise; drag reduction through laminar flow; advanced composite structural concepts for weight reduction; low NOX combustors; and propulsion and airframe integration for noise reduction and fuel-burn improvements. The ERA project will focus on environmental issues associated with aircraft, including fuel burn, emissions, and noise. The project will explore and document the feasibility, benefits, and technical risk of vehicle concepts and enabling technologies identified to have the potential to mitigate the impact of aviation on the environment. This research directly supports the national aeronautics research and development policy to develop appropriate environmental protection measures to ensure continued growth in air transportation. The primary structural concept being developed under the ERA program in the airframe technology element is the pultruded rod stitched efficient unitized structure (prseus) design. The prseus design approach is part of the ERA effort to address fuel burn (C02 emissions) by reducing the weight of advanced structures. Reducing fuel burn reduces the need to use resources and reduces pollution to the environment. The approach moves from safe-life to fail-safe design with a lightweight composite structure. Prseus represents a new concept in composite design theory and manufacturing methods. IT is a conscious progression away from conventional laminated and bonded assemblies toward larger one-piece panel designs with seamless transitions and damage-arrest interfaces such as stitch rows and tear straps. IT focuses on a new structural concept that integrates skin, stringers, and frame elements into a single large panel in which all elements are simultaneously cured (or CO-cured) in one high-temperature cure cycle. The resulting structure is a novel solution for addressing the demanding fuselage loading requirements inherent in a pressurized shaped vehicle like the hybrid wing body (HWB) or blended wing body (BWB) concept. The prseus concept builds upon, extends, and tailors these structural technologies in order to meet the demanding challenges associated with vehicles with shapes and load paths different from today s traditional wing and circular fuselage structures. Having demonstrated the unique capability of the hybrid wing body (HWB) pultruded rod stitched efficient unitized structure (prseus) structural concept to economically produce large integrated structural panels, the primary airframe design challenge now becomes the validation of the structural performance in the combined loading environment of the HWB pressure shell. Under these conditions, skin panels must not only have continuous load paths in both directions (i.e., NX and NY), they must also be effective in transmitting internal pressure loads (i.e., NZ) for the near-flat panel geometry. Demonstration of this cap