Synthetic Vision Enhances Situation Awareness and Rnp Capabilities for Terrain-challenged Approaches

The Synthetic Vision Systems (SVS) Project of Aviation Safety Program is striving to eliminate poor visibility as a causal factor in aircraft accidents as well as enhance operational capabilities of all aircraft through the display of computer generated imagery derived from an onboard database of terrain, obstacle, and airport information. To achieve these objectives, NASA 757 flight test research was conducted at the Eagle-Vail, Colorado airport to evaluate three SVS display types (Head-Up Display, Head-Down Size A, Head-Down Size X) and two terrain texture methods (photo-realistic, generic) in comparison to the simulated Baseline Boeing-757 Electronic Attitude Direction Indicator and Navigation / Terrain Awareness and Warning System displays. These independent variables were evaluated for situation awareness, path error, and workload while making approaches to Runway 25 and 07 and during simulated engine-out Cottonwood 2 and KREMM departures. The results of the experiment showed significantly improved situation awareness, performance, and workload for SVS concepts compared to the Baseline displays and confirmed the retrofit capability of the Head-Up Display and Size A SVS concepts. The research also demonstrated that the pathway and pursuit guidance used within the SVS concepts achieved required navigation performance (RNP) criteria. ∗ AIAA Associate Fellow, Aerospace Technologist † Aerospace Technologist ‡ AIAA Member, Aerospace Technologist § AIAA Member, Aerospace Technologist INTRODUCTION Limited visibility is the single most critical factor affecting both the safety and capacity of worldwide aviation operations. In commercial aviation alone, over 30-percent of all fatal accidents worldwide are categorized as controlled flight into terrain (CFIT), where a mechanically sound and normally functioning airplane is inadvertently flown into the ground, water, or an obstacle. The primary causes of these accidents are principally due to the lack of outside visual reference and lack of situation awareness. The NASA Aviation Safety Program’s Synthetic Vision Systems (SVS) Project is developing technologies with practical applications that will eliminate low visibility conditions as a causal factor to civil aircraft accidents, as well as replicate the operational benefits of flight operations in unlimited ceiling and visibility day conditions, regardless of the actual outside weather or lighting condition. The technologies will emphasize the costeffective use of synthetic/enhanced vision displays, worldwide navigation, terrain, obstruction, and airport databases, and Global Positioning System (GPS)derived navigation to eliminate “visibility-induced” (lack of vis ibility) errors for all aircraft categories (transports, General Aviation, rotorcraft). A major thrust of the SVS Project is to develop and demonstrate affordable, certifiable display configurations which provide intuitive out-the-window terrain and obstacle information, including guidance information for precision navigation and obstacle/obstruction avoidance for Commercial and Business aircraft. The safety benefit of SVS is projected to be the result of an intuitive cockpit display of terrain and obstacles that should help reduce, or even prevent, CFIT, which is the single greatest contributing factor to fatal worldwide airline and general aviation accidents. Other safety benefits include reduced runway incursions and loss-of-control accidents. Operational benefits potentially include more approach and departure options and lower visibility minimums for SVS-equipped aircraft. Because intuitive perspective displays can naturally depict effective precision pathway (tunnel) guidance concepts, SVS may also significantly improve flight path tracking performance and help meet new FAA required navigation performance (RNP) criteria. RNP is a statement of the navigation performance accuracy necessary for operation within a defined airspace. RNP type is a designator according to navigational performance accuracy in the horizontal plane (lateral and longitudinal position fixing). This designator invokes all of the navigation performance requirements AIAA's 3rd Annual Aviation Technology, Integration, and Operations (ATIO) Tech 17 19 November 2003, Denver, Colorado AIAA 2003-6814 This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States. https://ntrs.nasa.gov/search.jsp?R=20040040154 2017-09-13T21:43:43+00:00Z