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This briefing gives insight into the research activities and efforts being executed in order to integrate unmanned aircraft systems into the national airspace system. This briefing is to inform others of the UAS-NAS Projects progress and future directions.
This briefing provides a project overview and gives insight into the 2014 technical accomplishments for the UAS Integration in the NAS Project.
Description and Update of NASA UAS in the NAS Project
This presentation gives insight into the research activities and efforts being executed in order to integrate unmanned aircraft systems into the national airspace system. This briefing is to inform others of the UAS-NAS progress and future directions.
These cards are part of the Series 3 flight test documentation conducted between primary aircraft and intruder aircraft. This research is part of the UAS in the NAS Flight Test Program.
This presentation gives insight into the research activities and efforts being executed in order to integrate unmanned aircraft systems into the national airspace system. This briefing is to inform others of the UAS-NAS FY16 progress and future directions.
This presentation is an overview of the UAS-NAS Project and how flight testing is used to collect data to provide inputs in validating the RTCA MOPS.
This presentation is a high level overview of the flight testing that took place in 2015 for the UAS-NAS project. All topics in the presentation discussed at a high level and no technical details are provided.
This presentation contains the analysis results of NAS-wide fast-time simulations with UAS and VFR traffic for a single day for evaluating the performance of Detect-and-Avoid (DAA) alerting and guidance systems. This purpose of this study was to help refine and validate MOPS alerting and guidance requirements. In this study, we generated plots of all performance metrics that are specified by RTCA SC-228 Minimum Operational Performance Standards (MOPS): 1) to evaluate the sensitivity of alerting parameters on the performance metrics of each DAA alert type: Preventive, Corrective, and Warning alerts and 2) to evaluate the effect of sensor uncertainty on DAA alerting and guidance performance.
NAS (NASA Advanced Supercomputing) Division: Advanced Computing: High-End Computing Capability (HECC) Project; Quantum Artificial Intelligence Lab (QuAIL); NASA Earth Exchange (NEX); Data Analytics Infrastructure for NASA; Cloud Services for Science & Engineering Projects.
Aviation is projected to become an increasingly large contributor to greenhouse gas emissions. Condensation trails (contrails) are visible cloud trails of water vapor made from aircraft engine exhaust. One study estimated that persistent contrails have contributed about 57% of total Effective Radiative Forcing from aviation operations. Airspace management can reduce persistent contrails and related climate change impacts. NAS Digital Twin simulation capability and Autoresolver conflict management service can be utilized to investigate persistent contrail formation avoidance. On three of the four days analyzed, TTBW persistent contrail formation length was about 10 percentage points less than Boeing 737-800 (around 3% vs 13%). On average, altitude change maneuvers in simulation reduced persistent contrail formation length by 69.8% for 0.4% increase in fuel burn and 1.2% increase in flight duration.
The intent of the NAS Exploratory Concepts & Technologies (NExCT) is to catalyze airspace integration of diverse and scalable cooperative extensible traffic management (xTM) operations.
The design and fabrication of telemetry ground data processing equipment using commercial logic cards or modules are discussed. A microelectronics program was initiated to evaluate circuitry, packaging methods, and fabrication approaches necessary to produce a competitively procured logic system. The NAS-PAK logic system covering all phases of implementation is considered.
This investigation was to determine whether a Black Brant VC (BBVC) sounding rocket equipped with the Goddard Space Flight Center (GSFC) rate control system (RCS) would produce g-levels which are satisfactory for space processing. Accelerations measured by the Marshall Space Flight Center (MSFC) low-g accelerometer system (LGAS) were compared with accelerations calculated from measured payload RCS gyro data during a low-g flight of BBVC NAS 21.015 at White Sands Missile Range, N.M., on October 4, 1974. Accelerations of up to 0.0002 g existed at the LGAS accelerometers from 70 through 420 sec (5.8 min), with the exception of a spike at 101 sec of 0.0004 g which occurred when the RCS was activated the second time. Accelerations of 0.0001 g existed from 140 through 400 sec (4.3 min). Accelerations of 0.0002 g along the roll axis up to 150 sec and of 0.0015 g in the lateral plane at about 135 sec are being investigated by GSFC. They may be associated with leaking thruster valves or a leak in one of the heat pipe experiments. The vehicle rate buildup each time after the RCS nulls out are also being investigated by GSFC. This rate caused most of the 0.0001 g acceleration experienced after 150 sec into the flight. Aerodynamic drag produced no significant accelerations after about 80 sec. The principal conclusion was that the BBVC with the GSFC RCS produces g-levels satisfactory for space processing.
A collection of benchmark test kernels that measure supercomputer performance has been developed for the use of the NAS (Numerical Aerodynamic Simulation) program at the NASA Ames Research Center. This benchmark program is described in detail and the specific ground rules are given for running the program as a performance test.
The Computational Structural Mechanics (CSM) Activity at Langley Research Center is developing methods for structural analysis on modern computers. To facilitate that research effort, an applications development environment has been constructed to insulate the researcher from the many computer operating systems of a widely distributed computer network. The CSM Testbed development system was ported to the Numerical Aerodynamic Simulator (NAS) Cray-2, at the Ames Research Center, to provide a high end computational capability. This paper describes the implementation experiences, the resulting capability, and the future directions for the Testbed on supercomputers.
Two methods for solving linear systems of equations on the NAS Cray-2 are described. One is a direct method; the other is an iterative method. Both methods exploit the architecture of the Cray-2, particularly the vectorization, and are aimed at structural analysis applications. To demonstrate and evaluate the methods, they were installed in a finite element structural analysis code denoted the Computational Structural Mechanics (CSM) Testbed. A description of the techniques used to integrate the two solvers into the Testbed is given. Storage schemes, memory requirements, operation counts, and reformatting procedures are discussed. Finally, results from the new methods are compared with results from the initial Testbed sparse Choleski equation solver for three structural analysis problems. The new direct solvers described achieve the highest computational rates of the methods compared. The new iterative methods are not able to achieve as high computation rates as the vectorized direct solvers but are best for well conditioned problems which require fewer iterations to converge to the solution.
The Computational Structural Mechanics (CSM) activity is developing advanced structural analysis and computational methods that exploit high-performance computers. Methods are developed in the framework of the CSM testbed software system and applied to representative complex structural analysis problems from the aerospace industry. An overview of the CSM testbed methods development environment is presented and some numerical methods developed on a CRAY-2 are described. Selected application studies performed on the NAS CRAY-2 are also summarized.