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NASA NTRS2000

An Overview of the NASA Aviation Safety Program Propulsion Health Monitoring Element

The NASA Aviation Safety Program (AvSP) has been initiated with aggressive goals to reduce the civil aviation accident rate, To meet these goals, several technology investment areas have been identified including a sub-element in propulsion health monitoring (PHM). Specific AvSP PHM objectives are to develop and validate propulsion system health monitoring technologies designed to prevent engine malfunctions from occurring in flight, and to mitigate detrimental effects in the event an in-flight malfunction does occur. A review of available propulsion system safety information was conducted to help prioritize PHM areas to focus on under the AvSP. It is noted that when a propulsion malfunction is involved in an aviation accident or incident, it is often a contributing factor rather than the sole cause for the event. Challenging aspects of the development and implementation of PHM technology such as cost, weight, robustness, and reliability are discussed. Specific technology plans are overviewed including vibration diagnostics, model-based controls and diagnostics, advanced instrumentation, and general aviation propulsion system health monitoring technology. Propulsion system health monitoring, in addition to engine design, inspection, maintenance, and pilot training and awareness, is intrinsic to enhancing aviation propulsion system safety.

Simon, Donald L.↗

NASA NTRS2000

A Study of Airline Passenger Susceptibility to Atmospheric Turbulence Hazard

A simple, generic, simulation math model of a commercial airliner has been developed to study the susceptibility of unrestrained passengers to large, discrete gust encounters. The math model simulates the longitudinal motion to vertical gusts and includes (1) motion of an unrestrained passenger in the rear cabin, (2) fuselage flexibility, (3) the lag in the downwash from the wing to the tail, and (4) unsteady lift effects. Airplane and passenger response contours are calculated for a matrix of gust amplitudes and gust lengths of a simulated mountain rotor. A comparison of the model-predicted responses to data from three accidents indicates that the accelerations in actual accidents are sometimes much larger than the simulated gust encounters.

Stewart, Eric C.↗

NASA NTRS2000

Estimating The Rate of Technology Adoption for Cockpit Weather Information Systems

In February 1997, President Clinton announced a national goal to reduce the weather related fatal accident rate for aviation by 80% in ten years. To support that goal, NASA established an Aviation Weather Information Distribution and Presentation Project to develop technologies that will provide timely and intuitive information to pilots, dispatchers, and air traffic controllers. This information should enable the detection and avoidance of atmospheric hazards and support an improvement in the fatal accident rate related to weather. A critical issue in the success of NASA's weather information program is the rate at which the market place will adopt this new weather information technology. This paper examines that question by developing estimated adoption curves for weather information systems in five critical aviation segments: commercial, commuter, business, general aviation, and rotorcraft. The paper begins with development of general product descriptions. Using this data, key adopters are surveyed and estimates of adoption rates are obtained. These estimates are regressed to develop adoption curves and equations for weather related information systems. The paper demonstrates the use of adoption rate curves in product development and research planning to improve managerial decision processes and resource allocation.

Kauffmann, Paul↗

NASA NTRS2000

DHC-6 Twin Otter Tailplane Airfoil Section Testing in the Ohio State University 7x10 Wind Tunnel

Ice contaminated tailplane stall (ICTS) has been found to be responsible for 16 accidents with 139 fatalities over the last three decades, and is suspected to have played a role in other accidents and incidents. The need for fundamental research in this area has been recognized at three international conferences sponsored by the FAA since 1991. In order to conduct such research, a joint NASA/FAA Tailplane Icing Program was formed in 1994: the Ohio State University has played an important role in this effort. The program employs icing tunnel testing, dry wind tunnel testing, flight testing, and analysis using a six-degrees-of-freedom computer code tailored to this problem. A central goal is to quantify the effect of tailplane icing on aircraft stability and control to aid in the analysis of flight test procedures to identify aircraft susceptibility to ICTS. This report contains the results ot testing of a full scale 2D model of a tailplane section of NASA's Icing Research Aircraft, with and without ice shapes, in an Ohio State University 7 x 10 Low Speed wind tunnel in 1994. The results have been integrated into a comprehensive database of aerodynamic coefficients and stability and control derivatives that will permit detailed analysis of flight test results with the analytical computer program. The testing encompassed a full range of angles of attack and elevator deflections, as well as two velocities to evaluate Reynolds number effects. Lift, drag, pitching moment, and hinge moment coefficients were obtained. In addition. instrumentation for use during flight testing was verified to be effective, all components showing acceptable fidelity. Comparison of clean and iced airfoil results show the ice shapes causing a significant decrease in the magnitude of CLmax (from -1.3 to -0.64) and associated stall angle (from -18.6 deg to -8.2 deg). Furthermore, the ice shapes caused an increase in hinge moment coefficient of approximately 0.02, the change being markedly abrupt for one of the ice shapes. A noticeable effect of elevator deflection is that magnitude of the stall angle is decreased for negative (upward) elevator deflections. All these result are consistent with observed tailplane phenomena. and constitute an effective set of data for comprehensive analysis of ICTS

Hiltner, Dale↗

NASA NTRS2000

AWE: Aviation Weather Data Visualization Environment

Weather is one of the major causes of aviation accidents. General aviation (GA) flights account for 92% of all the aviation accidents, In spite of all the official and unofficial sources of weather visualization tools available to pilots, there is an urgent need for visualizing several weather related data tailored for general aviation pilots. Our system, Aviation Weather Data Visualization Environment AWE), presents graphical displays of meteorological observations, terminal area forecasts, and winds aloft forecasts onto a cartographic grid specific to the pilot's area of interest. Decisions regarding the graphical display and design are made based on careful consideration of user needs. Integral visual display of these elements of weather reports is designed for the use of GA pilots as a weather briefing and route selection tool. AWE provides linking of the weather information to the flight's path and schedule. The pilot can interact with the system to obtain aviation-specific weather for the entire area or for his specific route to explore what-if scenarios and make "go/no-go" decisions. The system, as evaluated by some pilots at NASA Ames Research Center, was found to be useful.

Spirkovska, Lilly↗

NASA NTRS1995

Modes in Supervisory Control Systems: Structure and Transitions

Mode confusion is becoming a major drawback in operator interaction with systems that allow for multiple levels of automation. This drawback has manifested itself in several mode related accidents and incidents in commercial aviation, military control systems, as well as high technology medical systems. In the domain of commercial aviation, there have been four recent airline accidents, all involving highly automated aircraft, in which mode related problems were present. Mode problems, we argue, stem from three principal factors: (1) mis-identification of the current mode, (2) difficulty in apprehending current mode behavior; and (3) difficulty in predicting the consequences of the next mode transition. This combination of factors may lead to mode confusion and possibly unwanted results. We define in this paper a mode as the system's manner of behavior. Any given system or machine, may have several ways of behaving. A controller, either human or machine, provides the input that triggers the transition from one mode of behavior to another. At any point in time, a machine may be in one mode or another modes are mutually exclusive. Complex systems are typically comprised of several subsystems, or components, each one with its own set of modes. Therefore, the status of the system at any point in time can be described as a vector of all the active modes.

Degani, Asaf↗

NASA NTRS1997

Reduction of Maintenance Error Through Focused Interventions

It is well known that a significant proportion of aviation accidents and incidents are tied to human error. In flight operations, research of operational errors has shown that so-called "pilot error" often involves a variety of human factors issues and not a simple lack of individual technical skills. In aircraft maintenance operations, there is similar concern that maintenance errors which may lead to incidents and accidents are related to a large variety of human factors issues. Although maintenance error data and research are limited, industry initiatives involving human factors training in maintenance have become increasingly accepted as one type of maintenance error intervention. Conscientious efforts have been made in re-inventing the "team" concept for maintenance operations and in tailoring programs to fit the needs of technical operations. Nevertheless, there remains a dual challenge: to develop human factors interventions which are directly supported by reliable human error data, and to integrate human factors concepts into the procedures and practices of everyday technical tasks. In this paper, we describe several varieties of human factors interventions and focus on two specific alternatives which target problems related to procedures and practices; namely, 1) structured on-the-job training and 2) procedure re-design. We hope to demonstrate that the key to leveraging the impact of these solutions comes from focused interventions; that is, interventions which are derived from a clear understanding of specific maintenance errors, their operational context and human factors components.

Kanki, Barbara G.↗

NASA NTRS1998

Cockpit Interruptions and Distractions: Effective Management Requires a Careful Balancing Act

Managing several tasks concurrently is an everyday part of cockpit operations. For the most part, crews handle concurrent task demands efficiently, yet crew preoccupation with one task to the detriment of performing other tasks is one of the more common forms of error in the cockpit. Most pilots are familiar with the December 1972 L1011 crash that occurred when the crew became preoccupied with a landing gear light malfunction and failed to notice that someone had inadvertently bumped off the autopilot. More recently a DC-9 landed gear-up in Houston when the crew, preoccupied with an stabilized approach, failed to recognize that the gear was not down because they had not switched the hydraulic pumps to high. We have recently started a research project to study why crews are vulnerable to these sorts of errors. As part of that project we reviewed NTSB reports of accidents attributed to crew error; we concluded that nearly half of these accidents involved lapses of attention associated with interruptions, distractions, or preoccupation with one task to the exclusion of another task. We have also analyzed 107 ASRS reports involving competing tasks; we present here some of our conclusions from those ASRS reports. These 107 reports involved 21 different types of routine tasks crews neglected at a critical moment while attending to another task. Sixty-nine percent of the neglected tasks involved either failure to monitor the current status or position of the aircraft or failure to monitor the actions of the pilot flying or taxiing. Thirty-four different types of competing activities distracted or preoccupied the pilots. Ninety percent of these competing activities fell into one of four broad categories: communication (e.g., discussion among crew or radio communication), heads-down work (e.g., programming the FMS or reviewing approach plates), responding to abnormals, or searching for VMC traffic. We will discuss examples of each of these four categories and suggest things crews can do to reduce their vulnerability to these and similar situations.

Dismukes, R. K.↗

NASA NTRS2002

Search and Rescue Operations of Aircraft in Africa: Some Compelling Issues

The world aviation community has felt the compelling need for a well-coordinated global programme for search and rescue operations of aircraft ever since commercial aviation was regulated in 1944. Guidelines and plans of action for search and rescue have therefore been considered critical in the event of an aircraft accident. This fact is eminently brought to bear in the continental regions of Africa and South America in particular, where vast expanses of land are still uninhabited or sparsely populated and controlled flight into terrain (CFIT-where an aircraft may crash on land while still under the control of technical crew) is a common occurrence. There are numerous guidelines that have been adopted under the umbrella of the International Civil Aviation Organization which are already in place for the provision of search and rescue operations pertaining to aircraft. However, when an accident occurs in the territory of a State, there are sensitivities involving the State in which the aircraft concerned was registered and issues of sovereignty which have to be considered. Additionally. issues such as the voluntary nature of the search and rescue services offered. confidentiality, timeliness of such operations, fairness and uniformity all play a critical role. This article addresses the issue of search and rescue operations in Africa and examines in some detail where the world aviation community is right now and where it is headed in this important field of human endeavour.

Abeyratne, Ruwantissa I. R.↗

NASA NTRS2002

Decomposition-Based Failure Mode Identification Method for Risk-Free Design of Large Systems

When designing products, it is crucial to assure failure and risk-free operation in the intended operating environment. Failures are typically studied and eliminated as much as possible during the early stages of design. The few failures that go undetected result in unacceptable damage and losses in high-risk applications where public safety is of concern. Published NASA and NTSB accident reports point to a variety of components identified as sources of failures in the reported cases. In previous work, data from these reports were processed and placed in matrix form for all the system components and failure modes encountered, and then manipulated using matrix methods to determine similarities between the different components and failure modes. In this paper, these matrices are represented in the form of a linear combination of failures modes, mathematically formed using Principal Components Analysis (PCA) decomposition. The PCA decomposition results in a low-dimensionality representation of all failure modes and components of interest, represented in a transformed coordinate system. Such a representation opens the way for efficient pattern analysis and prediction of failure modes with highest potential risks on the final product, rather than making decisions based on the large space of component and failure mode data. The mathematics of the proposed method are explained first using a simple example problem. The method is then applied to component failure data gathered from helicopter, accident reports to demonstrate its potential.

Tumer, Irem Y.↗

NASA NTRS2002

The Efficacy of Using Synthetic Vision Terrain-Textured Images to Improve Pilot Situation Awareness

The General Aviation Element of the Aviation Safety Program's Synthetic Vision Systems (SVS) Project is developing technology to eliminate low visibility induced General Aviation (GA) accidents. SVS displays present computer generated 3-dimensional imagery of the surrounding terrain on the Primary Flight Display (PFD) to greatly enhance pilot's situation awareness (SA), reducing or eliminating Controlled Flight into Terrain, as well as Low-Visibility Loss of Control accidents. SVS-conducted research is facilitating development of display concepts that provide the pilot with an unobstructed view of the outside terrain, regardless of weather conditions and time of day. A critical component of SVS displays is the appropriate presentation of terrain to the pilot. An experimental study is being conducted at NASA Langley Research Center (LaRC) to explore and quantify the relationship between the realism of the terrain presentation and resulting enhancements of pilot SA and performance. Composed of complementary simulation and flight test efforts, Terrain Portrayal for Head-Down Displays (TP-HDD) experiments will help researchers evaluate critical terrain portrayal concepts. The experimental effort is to provide data to enable design trades that optimize SVS applications, as well as develop requirements and recommendations to facilitate the certification process. In this part of the experiment a fixed based flight simulator was equipped with various types of Head Down flight displays, ranging from conventional round dials (typical of most GA aircraft) to glass cockpit style PFD's. The variations of the PFD included an assortment of texturing and Digital Elevation Model (DEM) resolution combinations. A test matrix of 10 terrain display configurations (in addition to the baseline displays) were evaluated by 27 pilots of various backgrounds and experience levels. Qualitative (questionnaires) and quantitative (pilot performance and physiological) data were collected during the experimental runs. This paper focuses on the experimental set-up and final physiological results of the TP-HDD simulation experiment. The physiological measures of skin temperature, heart rate, and muscle response, show a decreased engagement (while using the synthetic vision displays as compared to the baseline conventional display) of the sympathetic and somatic nervous system responses which, in turn, indicates a reduced level of mental workload. This decreased level of workload is expected to enable improvement in the pilot's situation and terrain awareness.

Uenking, Michael D.↗

NASA NTRS2002

[High Pressure Gas Tanks]

Four high-pressure gas tanks, the basis of this study, were especially made by a private contractor and tested before being delivered to NASA Kennedy Space Center. In order to insure 100% reliability of each individual tank the staff at KSC decided to again submit the four tanks under more rigorous tests. These tests were conducted during a period from April 10 through May 8 at KSC. This application further validates the predictive safety model for accident prevention and system failure in the testing of four high-pressure gas tanks at Kennedy Space Center, called Continuous Hazard Tracking and Failure Prediction Methodology (CHTFPM). It is apparent from the variety of barriers available for a hazard control that some barriers will be more successful than others in providing protection. In order to complete the Barrier Analysis of the system, a Task Analysis and a Biomechanical Study were performed to establish the relationship between the degree of biomechanical non-conformities and the anomalies found within the system on particular joints of the body. This relationship was possible to obtain by conducting a Regression Analysis to the previously generated data. From the information derived the body segment with the lowest percentage of non-conformities was the neck flexion with 46.7%. Intense analysis of the system was conducted including Preliminary Hazard Analysis (PHA), Failure Mode and Effect Analysis (FMEA), and Barrier Analysis. These analyses resulted in the identification of occurrences of conditions, which may be becoming hazardous in the given system. These conditions, known as dendritics, may become hazards and could result in an accident, system malfunction, or unacceptable risk conditions. A total of 56 possible dendritics were identified. Work sampling was performed to observe the occurrence each dendritic. The out of control points generated from a Weighted c control chart along with a Pareto analysis indicate that the dendritics "Personnel not Wearing Proper Protective and Hose/tubing located in high-traffic area" which account for 59.18% of total dendritic frequency need to be addressed to reduce the chance of a hazard from occurring. However, the occurrences of some dendritics are more important than others. As a result immediate, from a Weighted c perspective, corrective action should be taken to ameliorate the cause of the Class A dendritic "Personnel located under suspended or moving loads" rather than just the most commonly occurring dendritics. In any case the vast majority of data obtained indicates that testing operations possess a relatively high degree of safety.

Quintana, Rolando↗

NASA NTRS2002

Toward a Concept of Operations for Aviation Weather Information Implementation in the Evolving National Airspace System

The capacity of the National Airspace System is being stressed due to the limits of current technologies. Because of this, the FAA and NASA are working to develop new technologies to increase the system's capacity which enhancing safety. Adverse weather has been determined to be a major factor in aircraft accidents and fatalities and the FAA and NASA have developed programs to improve aviation weather information technologies and communications for system users The Aviation Weather Information Element of the Weather Accident Prevention Project of NASA's Aviation Safety Program is currently working to develop these technologies in coordination with the FAA and industry. This paper sets forth a theoretical approach to implement these new technologies while addressing the National Airspace System (NAS) as an evolving system with Weather Information as one of its subSystems. With this approach in place, system users will be able to acquire the type of weather information that is needed based upon the type of decision-making situation and condition that is encountered. The theoretical approach addressed in this paper takes the form of a model for weather information implementation. This model addresses the use of weather information in three decision-making situations, based upon the system user's operational perspective. The model also addresses two decision-making conditions, which are based upon the need for collaboration due to the level of support offered by the weather information provided by each new product or technology. The model is proposed for use in weather information implementation in order to provide a systems approach to the NAS. Enhancements to the NAS collaborative decision-making capabilities are also suggested.

McAdaragh, Raymon M.↗

NASA NTRS2002

Terrain Portrayal for Head-Down Displays Experiment

The General Aviation Element of the Aviation Safety Program's Synthetic Vision Systems (SVS) Project is developing technology to eliminate low visibility induced General Aviation (GA) accidents. SVS displays present computer generated 3-dimensional imagery of the surrounding terrain on the Primary Flight Display (PFD) to greatly enhance pilot's situation awareness (SA), reducing or eliminating Controlled Flight into Terrain, as well as Low-Visibility Loss of Control accidents. SVS-conducted research is facilitating development of display concepts that provide the pilot with an unobstructed view of the outside terrain, regardless of weather conditions and time of day. A critical component of SVS displays is the appropriate presentation of terrain to the pilot. An experimental study has been conducted at NASA Langley Research Center (LaRC) to explore and quantify the relationship between the realism of the terrain presentation and resulting enhancements of pilot SA and pilot performance. Composed of complementary simulation and flight test efforts, Terrain Portrayal for Head-Down Displays (TP-HDD) experiments will help researchers evaluate critical terrain portrayal concepts. The experimental effort is to provide data to enable design trades that optimize SVS applications, as well as develop requirements and recommendations to facilitate the certification process. This paper focuses on the experimental set-up and preliminary qualitative results of the TP-HDD simulation experiment. In this experiment a fixed based flight simulator was equipped with various types of Head Down flight displays, ranging from conventional round dials (typical of most GA aircraft) to glass cockpit style PFD's. The variations of the PFD included an assortment of texturing and Digital Elevation Model (DEM) resolution combinations. A test matrix of 10 terrain display configurations (in addition to the baseline displays) were evaluated by 27 pilots of various backgrounds and experience levels. Qualitative (questionnaires) and quantitative (pilot performance and physiological) data were collected during the experimental runs. Preliminary results indicate that all of the evaluation pilots favored SVS displays over standard gauges, in terms of terrain awareness, SA, and perceived pilot performance. Among the terrain portrayal concepts tested, most pilots preferred the higher-resolution DEM. In addition, with minimal training, low-hour VFR evaluation pilots were able to negotiate a precision approach using SVS displays with a tunnel in the sky guidance concept.

Hughes, Monica F.↗

NASA NTRS2002

Convectively Induced Turbulence Encountered During NASA's Fall-2000 Flight Experiments

Aircraft encounters with atmospheric turbulence are a leading cause of in-flight injuries aboard commercial airliners and cost the airlines millions of dollars each year. Most of these injuries are due to encounters with turbulence in and around convection. In a recent study of 44 turbulence accident reports between 1990 and 1996, 82% of the cases were found to be near or within convective activity (Kaplan et al. 1999). According to NTSB accident reports, pilots' descriptions of these turbulence encounters include 'abrupt', 'in Instrument Meteorological Conditions (IMC)', 'saw nothing on the weather radar', and 'the encounter occurred while deviating around' convective activity. Though the FAA has provided guidelines for aircraft operating in convective environments, turbulence detection capability could decrease the number of injuries by alerting pilots of a potential encounter. The National Aeronautics and Space Administration, through its Aviation Safety Program, is addressing turbulence hazards through research, flight experiments, and data analysis. Primary focus of this program element is the characterization of turbulence and its environment, as well as the development and testing of hazard estimation algorithms for both radar and in situ detection. The ultimate goal is to operationally test sensors that will provide ample warning prior to hazardous turbulence encounters. In order to collect data for support of these activities, NASA-Langley's B-757 research aircraft was directed into regions favorable for convectively induced turbulence (CIT). On these flights, the airborne predictive wind shear (PWS) radar, augmented with algorithms designed for turbulence detection, was operated in real time to test this capability. In this paper, we present the results of two research flights when turbulence was encountered. Described is an overview of the flights, the general radar performance, and details of four encounters with severe turbulence.

Hamilton, David W.↗

NASA NTRS2003

Piloted Evaluation of Modernized Limited Authority Control Laws in the NASA-Ames Vertical Motion Simulator (VMS)

The UH-60 BLACK HAWK was designed in the 1970s, when the US Army primarily operated during the day in good visual conditions. Subsequently, the introduction of night-vision goggles increased the BLACK HAWK'S mission effectiveness, but the accident rate also increased. The increased accident rate is strongly tied to increased pilot workload as a result of a degradation in visual cues. Over twenty years of research in helicopter flight control and handling qualities has shown that these degraded handling qualities can be recovered by modifying the response type of the helicopter in low speed flight. Sikorsky Aircraft Corporation initiated a project under the National Rotorcraft Technology Center (NRTC) to develop modern flight control laws while utilizing the existing partial authority Stability Augmentation System (SAS) of the BLACK HAWK. This effort resulted in a set of Modernized Control Laws (MCLAWS) that incorporate rate command and attitude command response types. Sikorsky and the US Army Aeroflightdynamics Directorate (AFDD) conducted a piloted simulation on the NASA-Ames Vertical h4otion Simulator, to assess potential handling qualities and to reduce the risk of subsequent implementation and flight test of these modern control laws on AFDD's EH-60L helicopter. The simulation showed that Attitude Command Attitude Hold control laws in pitch and roll improve handling qualities in the low speed flight regime. These improvements are consistent across a range of mission task elements and for both good and degraded visual environments. The MCLAWS perform better than the baseline UH-60A control laws in the presence of wind and turbulence. Finally, while the improved handling qualities in the pitch and roll axis allow the pilot to pay more attention to the vertical axis and hence altitude performance also improves, it is clear from pilot comments and altitude excursions that the addition of an Altitude Hold function would further reduce workload and improve overall handling qualities of the aircraft.

Sahasrabudhe, Vineet↗

NASA NTRS2003

NASA Aviation Safety Program Systems Analysis/Program Assessment Metrics Review

The goal of this project is to evaluate the metrics and processes used by NASA's Aviation Safety Program in assessing technologies that contribute to NASA's aviation safety goals. There were three objectives for reaching this goal. First, NASA's main objectives for aviation safety were documented and their consistency was checked against the main objectives of the Aviation Safety Program. Next, the metrics used for technology investment by the Program Assessment function of AvSP were evaluated. Finally, other metrics that could be used by the Program Assessment Team (PAT) were identified and evaluated. This investigation revealed that the objectives are in fact consistent across organizational levels at NASA and with the FAA. Some of the major issues discussed in this study which should be further investigated, are the removal of the Cost and Return-on-Investment metrics, the lack of the metrics to measure the balance of investment and technology, the interdependencies between some of the metric risk driver categories, and the conflict between 'fatal accident rate' and 'accident rate' in the language of the Aviation Safety goal as stated in different sources.

Louis, Garrick E.↗

NASA NTRS2004

Context-Aware Intelligent Assistant Approach to Improving Pilot's Situational Awareness

Faulty decision making due to inaccurate or incomplete awareness of the situation tends to be the prevailing cause of fatal general aviation accidents. Of these accidents, loss of weather situational awareness accounts for the largest number of fatalities. We describe a method for improving weather situational awareness through the support of a contextaware,domain and task knowledgeable, personalized and adaptive assistant. The assistant automatically monitors weather reports for the pilot's route of flight and warns her of detected anomalies. When and how warnings are issued is determined by phase of flight, the pilot s definition of acceptable weather conditions, and the pilot's preferences for automatic notification. In addition to automatic warnings, the pilot is able to verbally query for weather and airport information. By noting the requests she makes during the approach phase of flight, our system learns to provide the information without explicit requests on subsequent flights with similar conditions. We show that our weather assistant decreases the effort required to maintain situational awareness by more than 5.5 times when compared to the conventional method of in-flight weather briefings.

Spirkovska, Lilly↗