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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
NASA NTRS2013

Acceptability of Flight Deck-Based Interval Management Crew Procedures

The Interval Management for Near-term Operations Validation of Acceptability (IM-NOVA) experiment was conducted at the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) in support of the NASA Next Generation Air Transportation System (NextGen) Airspace Systems Program's Air Traffic Management Technology Demonstration - 1 (ATD-1). ATD-1 is intended to showcase an integrated set of technologies that provide an efficient arrival solution for managing aircraft using NextGen surveillance, navigation, procedures, and automation for both airborne and ground-based systems. The goal of the IM-NOVA experiment was to assess if procedures outlined by the ATD-1 Concept of Operations, when used with a minimum set of Flight deck-based Interval Management (FIM) equipment and a prototype crew interface, were acceptable to and feasible for use by flight crews in a voice communications environment. To investigate an integrated arrival solution using ground-based air traffic control tools and aircraft automatic dependent surveillance broadcast (ADS-B) tools, the LaRC FIM system and the Traffic Management Advisor with Terminal Metering and Controller Managed Spacing tools developed at the NASA Ames Research Center (ARC) were integrated in LaRC's Air Traffic Operations Laboratory. Data were collected from 10 crews of current, qualified 757/767 pilots asked to fly a high-fidelity, fixed based simulator during scenarios conducted within an airspace environment modeled on the Dallas-Fort Worth (DFW) Terminal Radar Approach Control area. The aircraft simulator was equipped with the Airborne Spacing for Terminal Area Routes algorithm and a FIM crew interface consisting of electronic flight bags and ADS-B guidance displays. Researchers used "pseudo-pilot" stations to control 24 simulated aircraft that provided multiple air traffic flows into DFW, and recently retired DFW air traffic controllers served as confederate Center, Feeder, Final, and Tower controllers. Pilot participant feedback indicated that the procedures used by flight crews to receive and execute interval management (IM) clearances in a voice communications environment were logical, easy to follow, did not contain any missing or extraneous steps, and required the use of an acceptable level of workload. The majority of the pilot participants found the IM concept, in addition to the proposed FIM crew procedures, to be acceptable and indicated that the ATD-1 procedures can be successfully executed in a near-term NextGen environment.

Murdock, Jennifer L.↗
NASA NTRS2017

Evaluation of Approval Request 47; Call for Release Procedures for Charlotte Douglas International Airport

NASA is collaborating with the Federal Aviation Administration (FAA) and aviation industry partners to develop and demonstrate new concepts and technologies for Integrated Arrival, Departure, and Surface (IADS) traffic management capabilities under the Airspace Technology Demonstration 2 (ATD-2) project. One of the goals of the IADS capabilities in the ATD-2 project is to increase predictability and throughput of airspace operations by improving Traffic Management Initiative (TMI) compliance. This paper focuses on the Approval Request (APREQ) procedures developed for the ATD-2 project between the Air Traffic Control (ATC) Tower at Charlotte Douglas International Airport and Washington Center. In March 2017, NASA conducted a Human-in-the-Loop (HITL) simulation to evaluate the operational procedures and information requirements for the APREQ procedures in the ATD-2 IADS system between ATC Tower and Center. The findings from the HITL are used to compare ATD-2 APREQ procedures with information about current day APREQ procedures.

Stevens, Lindsay↗
NASA NTRS2017

Experimental Verification of Buffet Calculation Procedure Using Unsteady Pressure-Sensitive Paint

Typically, a limited number of dynamic pressure sensors is employed to determine the unsteady aerodynamic forces on large, slender aerospace structures. This paper describes a robust calculation procedure based on frequency-specific correlation lengths and validation from an experiment conducted on a flat panel coated with fast response pressure-sensitive paint. The first part of the paper describes the procedure used to analyze the pressure sensitive paint images and a calibration method using dynamic pressure transducers. Excellent comparison in spectra, coherence, and phase, measured via pressure-sensitive paint and dynamic pressure sensors, validates the pressure-sensitive paint data. The second part of the paper describes the buffet validation process, the first step of which was to use pressure histories from all pixels to determine the true force fluctuations. In the next step, only a selected number of pixels was chosen as virtual sensors, and a correlation-length-based buffet calculation procedure was applied to determine modeled force fluctuations. By progressively decreasing the number of virtual sensors, it was observed that the present calculation procedure was able to make a close estimate of the true unsteady forces only from eight sensors. It is believed that the present work provides the first validation of a buffet calculation procedure.

Buffet↗
NASA NTRS2018

System and Method for Providing Visualization Aids for Effective Interval Management Procedure Execution

Methods and apparatus are provided for simulating an interval management (IM) procedure for an ownship aircraft and a target aircraft before the start of the performance of the IM procedure. The method comprises receiving an IM clearance message from air traffic control (ATC), parsing the received IM clearance message into parsed information components identifying the complexity of the IM clearance message based on the number of elements in the information components, generating a flight chart depicting the area over which the proposed IM procedure is to traverse using the mapping information wherein the flight chart includes a vertical view and a plan view, and simulating the IM procedure on the generated flight chart before any steps of the IM procedure are performed.

Kashi, Rajanikanth Nagaraj↗
NASA NTRS2019

Exploration of Near-Term Potential Routes and Procedures for Urban Air Mobility

Urban air mobility is gaining interest as the need for On Demand Mobility in today's congested traffic is becoming high in metropolitan areas. Urban Air Mobility (UAM) is envisioned as a concept to transport passengers and cargo safely and efficiently using innovative aircraft in the urban areas. It is expected to improve mobility for the general public, decongest road traffic, reduce transport time and reduce the strain on existing public transport networks. There exist several challenges to Urban Air Mobility (UAM) such as integration of procedures with airspace and the airport, noise levels that are acceptable to the general public, public safety, public acceptance, vehicle certification, and more. Most of the research in the United States and European skies (DLR - German Aerospace Center) related to urban areas has focused on small UAS (Unmanned Aircraft Systems) flights (NASA's UTM (UAS Traffic Management) research) and their integration with the airspace and building safe operations in densely populated areas. Previous studies on UAM have focused on fast time simulations of the routes that are separated via a separation service and network of routes. Similarly, research in Europe has focused on the approach profile for these innovative aircraft, vertiports and battery life among others. UAM as a part of the On-Demand Mobility effort has provided some guidelines for operations as shown below: Does not require additional ATC (Air Traffic Control) infrastructure; Does not impose additional workload on ATC; Does not restrict operations of traditional airspace users; Will meet appropriate safety thresholds and requirements; Will prioritize operational scalability; Will allow flexibility where possible and structure where necessary. This paper explores potential routes and procedures in a Human-In-The-Loop (HITL) experiment that could be applied in the near-term to allow integration of UAM flights into the airspace as well as a large airport. The airspace that was explored was Dallas Fort Worth (DFW) airspace managed by the DFW East Tower in South Flow only. In addition, Dallas Love Field (DAL) and Addison (ADS) airspace were also part of the testbed. The initial set of routes investigated in this study were published helicopter routes in the DFW area. Figure 1 shows class B airspace in DFW area and the origin/destination city pairs where UAM flights flew along with helicopter routes shown in blue. The research focused on exploring procedures for integrating UAM flights into Class Bravo and Class Delta airspace. Three different communication procedures, evaluated with three different levels of UAM traffic, are shown in Table 1. The current day routes were evaluated with current day communication procedures were explored as the first condition. The current day routes were also evaluated in the second condition with reduced communications, which was assumed due to the presence of a Letter Of Agreement (LOA). The purpose of the LOA was to reduce the verbiage associated with pilots getting clearance to Class B airspace from the controllers, pre-assigning beacons codes to the UAM flights, separate routes by assigning altitudes and speeds to flights going in any one direction. Flights were expected to automatically change frequency when exiting Class B airspace, thus transition points for entry and exit points were also specified in the LOA.

Urban Air Mobility↗
NASA NTRSDate not supplied

Initial Assessment of Lost Command and Control Link Procedures

This paper presents an initial assessment of lost command and control (LC2L) procedures for large Uncrewed Aircraft Systems (UAS) in a simulated representative airspace environment using real airspace procedures. The experiment matrix consists of nine different flight routes: four nominal, four following current LC2L procedures, and one that routes the UAS more conservatively through less-busy airspace. For each route, eleven simulated UAS flights – in ten-minute increments – were flown into Fort Worth Alliance Airport following a real Instrument Approach Procedure. The simulated UAS flew amongst real recorded tracks of approximately 4,700 flights on January 18, 2022. The analysis focused primarily on the number of aircraft with which each UAS lost separation and where the losses occurred. This work presents a significant increase in testing capability and provides the foundation for further verification and validation of LC2L procedures using additional analysis metrics.

Uncrewed aircraft↗
NASA NTRSDate not supplied

Initial Assessment of Lost Command and Control Link Procedures

This paper presents an initial assessment of lost command and control (LC2L) procedures for large Uncrewed Aircraft Systems (UAS) in a simulated representative airspace environment using real airspace procedures. The experiment matrix consists of nine different flight routes: four nominal, four following current LC2L procedures, and one that routes the UAS more conservatively through less-busy airspace. For each route, eleven simulated UAS flights – in ten-minute increments – were flown into Fort Worth Alliance Airport following a real Instrument Approach Procedure. The simulated UAS flew amongst real recorded tracks of approximately 4,700 flights on January 18, 2022. The analysis focused primarily on the number of aircraft with which each UAS lost separation and where the losses occurred. This work presents a significant increase in testing capability and provides the foundation for further verification and validation of LC2L procedures using additional analysis metrics.

uncrewed aircraft↗
NASA NTRSDate not supplied

Why Didn't They Just Follow the Procedure?

It is often said that to err is human and that procedures are in place to prevent people from making mistakes. It's true that failures can be traced to human limitation, but what's more important is that all successes, all safe operations are the result of human capabilities. And while it's true that good procedures can help avoid error, it's also the case that procedures have their own limitations. This talk highlights the limits of procedures and the resilience people bring to operations. It discusses ways to change the common narrative that people are the creators of safety rather than only the source of error and failure, and it proposes an approach to the design of procedures that supports the human operator.

operations↗
DOE OSTI2024

Light Water Reactor Sustainability Program: Use of Time Distributions to Predict Operator Procedure Performance in Dynamic Human Reliability Analysis

The Human Unimodel for Nuclear Technology to Enhance Reliability (HUNTER) framework affords software capable of conducting human reliability analysis (HRA) using a dynamic approach built around operating procedures (OPs) from nuclear power plants (NPPs). Previous HUNTER reports document the development of this software tool, the coupling of HUNTER to the simulator code, the collection of operator performance data by using simulators to calibrate HUNTER models, and linking HUNTER to probabilistic risk assessment (PRA) software. The present report largely addresses two topics. The first is a new function in HUNTER called the HUNTER Procedure Performance Predictor (P3). HUNTER P3 uses HUNTER’s built in Monte Carlo tools featuring human performance variability to identify potential error traps in procedures. The second topic is time distribution analysis to generate time inputs for dynamic HRA. The current analysis was performed to investigate time distributions for task primitives, which are the minimum task unit of analysis used in dynamic HRA modeling. Using the time distribution data, the elapsed time for human actions in an extended loss of AC power (ELAP) scenario is then investigated. Time data and prediction are essential for modeling procedure performance.

99 GENERAL AND MISCELLANEOUS↗
NASA NTRS2023

Procedure Automation Rating Matrix

The National Aeronautics and Space Administration (NASA) Advanced Air Mobility (AAM) National Campaign (NC) is researching the means by which future Urban Air Mobility (UAM) aircraft will operate safely in an integrated and scalable airspace architecture. Consistent with this objective, the NASA NC Airspace Procedures team designed a matrix to evaluate UAM instrument flight procedure design, flyability and interoperability of candidate departure, enroute, and approach architectures in live flight or simulation. The Procedure Automation Rating Matrix (PARM) is a multi-dimensional rating scale designed to provide direct feedback from test pilots and operators to airspace procedure designers developing airspace constructs for the integration and scalability of AAM operations in the National Airspace System (NAS). The PARM is assessed using a hierarchical decision tree that guides the operator through a ten-point alpha-numeric rating scale initiated either with or without the use of automation.

National Campaign↗
NASA NTRS2024

eVTOL Vehicle-Agnostic Instrument Flight Procedures Test Plan

NASA Advanced Air Mobility National Campaign is researching the utility of electric vertical takeoff and land (eVTOL) advanced air mobility (AAM) instrument flight procedures. The result will be dynamic and tailored procedures that align to the following modus operandi: maximize safety, optimize efficiency, support passenger comfort and minimize acoustics. This is achieved through dynamic airspace procedure design, which is a modular approach to create an airspace construct that customizes procedures to vehicle design and configuration, operation and environmental conditions. The test plan supports different eVTOL platforms and envisioned operations for flight test or simulation and may be leveraged by AAM aircraft manufacturers and operators for any given aircraft, location and operation.

eVTOL test plan↗
NASA NTRS1972

Real-air data reduction procedures based on flow parameters measured in the test section of supersonic and hypersonic facilities

Data-reduction procedures for determining free stream and post-normal shock kinetic and thermodynamic quantities are derived. These procedures are applicable to imperfect real air flows in thermochemical equilibrium for temperatures to 15 000 K and a range of pressures from 0.25 N/sq m to 1 GN/sq m. Although derived primarily to meet the immediate needs of the 6-inch expansion tube, these procedures are applicable to any supersonic or hypersonic test facility where combinations of three of the following flow parameters are measured in the test section: (1) Stagnation pressure behind normal shock; (2) freestream static pressure; (3) stagnation point heat transfer rate; (4) free stream velocity; (5) stagnation density behind normal shock; and (6) free stream density. Limitations of the nine procedures and uncertainties in calculated flow quantities corresponding to uncertainties in measured input data are discussed. A listing of the computer program is presented, along with a description of the inputs required and a sample of the data printout.

Miller, C. G., III↗
NASA NTRS1971

Boundary condition computational procedures for inviscid, supersonic steady flow field calculations

Results are given of a comparative study of numerical procedures for computing solid wall boundary points in supersonic inviscid flow calculatons. Twenty five different calculation procedures were tested on two sample problems: a simple expansion wave and a simple compression (two-dimensional steady flow). A simple calculation procedure was developed. The merits and shortcomings of the various procedures are discussed, along with complications for three-dimensional and time-dependent flows.

Abbett, M. J.↗
NASA NTRS1973

Round-off errors in cutting plane algorithms based on the revised simplex procedure

This report statistically analyzes computational round-off errors associated with the cutting plane approach to solving linear integer programming problems. Cutting plane methods require that the inverse of a sequence of matrices be computed. The problem basically reduces to one of minimizing round-off errors in the sequence of inverses. Two procedures for minimizing this problem are presented, and their influence on error accumulation is statistically analyzed. One procedure employs a very small tolerance factor to round computed values to zero. The other procedure is a numerical analysis technique for reinverting or improving the approximate inverse of a matrix. The results indicated that round-off accumulation can be effectively minimized by employing a tolerance factor which reflects the number of significant digits carried for each calculation and by applying the reinversion procedure once to each computed inverse. If 18 significant digits plus an exponent are carried for each variable during computations, then a tolerance value of 0.1 x 10 to the minus 12th power is reasonable.

Moore, J. E.↗
NASA NTRS1973

Boundary condition calculation procedures for inviscid supersonic flow fields.

Results are given of a comparative study of numerical procedures for computing solid wall and sharp shock boundary points in supersonic inviscid flow calculations. Thirty different calculation procedures were tested on four sample problems in two dimensional steady flow. A new simple but accurate calculation procedure was developed for solid wall boundary point calculations. The merits and shortcomings of the various procedures are thoroughly discussed.

Abbett, M. J.↗
NASA NTRS1974

Applicability of NASA (ARC) two-segment approach procedures to Boeing Aircraft

An engineering study to determine the feasibility of applying the NASA (ARC) two-segment approach procedures and avionics to the Boeing fleet of commercial jet transports is presented. This feasibility study is concerned with the speed/path control and systems compability aspects of the procedures. Path performance data are provided for representative Boeing 707/727/737/747 passenger models. Thrust margin requirements for speed/path control are analyzed for still air and shearing tailwind conditions. Certification of the two-segment equipment and possible effects on existing airplane certification are discussed. Operational restrictions on use of the procedures with current autothrottles and in icing or reported tailwind conditions are recommended. Using the NASA/UAL 727 procedures as a baseline, maximum upper glide slopes for representative 707/727/737/747 models are defined as a starting point for further study and/or flight evaluation programs.

Allison, R. L.↗
NASA NTRS1973

Development of a computer-aided procedure for the national program of inspection of dams

An effort was undertaken to determine the utility of ERTS-1 MSS data, together with automatic data processing (ADP) techniques, to detect and locate surface water, and transfer the related technology to the Texas Water Rights Commission (TWRC). A test site was selected, ERTS-1 MSS and ancillary data obtained, and existent ADP classification programs applied. During the course of this effort a linear discriminant function was developed. The results were evaluated for potential candidates for a transferable procedure. A computer-aided technique using a linear discriminant function was selected and recommended, for inclusion in an operational system, which met detection and location criteria. Specifically, evaluation of the selected computer-aided procedure for the test site resulted in the detection of 100 percent of areas of surface water 10 acres or greater in areal extent and the geographic location of areas classified as water to a positional accuracy of 1000 feet or closer. The procedure was recommended for inclusion in an operational computer-aided procedure for transfer to TWRC.

Source record↗
NASA NTRS1975

Computational procedure for three-dimensional boundary layers on aircraft and aerospace vehicles

An implicit numerical procedure is developed to solve the full three-dimensional laminar, boundary layer equations over realistic aircraft and spacecraft configurations. This procedure utilizes splined functions in the direction normal to the surface and finite differences in the cross flow direction. Calculation of off-pitch plane attachment and detachment lines can be calculated. The solution procedure permits the incorporation of a wide variety of turbulent models and boundary conditions including; entropy layer procedures, specified surface temperatures or heat flux distributions, surface catalysis, mass addition, and the coupling to both three-dimensional inviscid codes and surface ablation codes. In addition, reasonable computing times are obtained.

Kendall, R. M.↗