Smaaart task order: task title: aerodynamic testing support for investigation of the hybrid wing body N2A-exte configuration in the 14- by 22-foot subsonic tunnel 1.0 introduction/background: NASA…

Smaaart task order: task title: aerodynamic testing support for investigation of the hybrid wing body N2A-exte configuration in the 14- by 22-foot subsonic tunnel 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. One unconventional aircraft configuration, referred to as the hybrid wing body (HWB), has been shown to have the potential to significantly reduce fuel burn while simultaneously reducing noise levels on the ground. The combination of upper surface engine placement in conjunction with the large HWB planform enable an effective engine noise shielding configuration. National research announcement (NRA) contract NNL07AA54C, entitled: acoustic prediction methodology and test validation for an efficient low-noise hybrid wing body subsonic transport, was awarded to the boeing company in 2007 with work being initiated on october 1 of that year. This 3-year NRA contract was conducted to: (1) develop a hybrid wing body (HWB) subsonic transport configuration capable of meeting the NASA subsonic fixed wing (SFW) reduced noise and fuel burn goals; (2) develop improved noise prediction methods; (3) design and fabricate a wind tunnel model for testing in the larc 14- by 22-foot subsonic tunnel to validate predictions; and (4) assess the low-speed aerodynamic characteristics of the HWB configuration developed. NRA contract NNL07AA54C is a significant part of the environmentally responsible aviation (ERA) project, and IT directly supports the goals of exploring and documenting the feasibility, benefits, and technical risk of vehicle concepts and enabling technologies that will reduce the impact of aviation on the environment. Due to extended configuration design efforts and extended wind tunnel model design and fabrication efforts within the above mentioned NRA contract, the 3-year time period ran out prior to the wind tunnel model and model support system being available for testing. However, plans are currently in place to conduct the initial wind tunnel investigation within the next few months. This investigation is directed toward an assessment of the low-speed aerodynamic characteristics of the HWB configuration developed. The configuration developed, designated as the HWB-N2A-exte, is deemed to be capable of meeting