Pilot Workload Research Articles

Pilot Performance, Workload, and Situation Awareness During Lunar Landing Mode Transitions

Aircraft and spacecraft pilots frequently change their level of supervisory control between full autopilot and other modes, providing varying levels of manual control. Therefore, multimodal systems must transition “gracefully,” meaning without unsafe decreases in flight performance or unacceptable changes in workload or situation awareness. Thirteen subjects flew a fixed base simulation of the NASA Constellation Program Altair lunar lander that transitioned from full autopilot to one of three flight-director-guided rate-command attitude hold manual control modes. After training, each subject flew 24 approaches, half of which included a landing point redesignation at the time of the mode transition requiring the pilot to null additional guidance errors. Bedford subjective workload and two-choice embedded secondary task response times were used to quantify temporal changes in mental workload. Situation awareness transients were detected by analysis of a tertiary task, verbal callouts of altitude, fuel, and terrain hazards. Graceful transitions were particularly difficult because Altair’s large inertia made the plant dynamics relatively sluggish. Transitions to manual control increased subjective and objective workloads and decreased callout accuracy in proportion to the number of flight control axes being manually commanded.

Cornering Law

We investigated skill development and workload of pilots driving teleoperated unmanned ground vehicles (UGVs) through different apertures and viewpoints using the cornering law. Due to technological and cost restraints, humans are still needed for tasks involving UGVs. Operators of teleoperated UGVs are likely to have less situation awareness and thus are more prone to getting stuck or damaged when negotiating apertures.To our knowledge, the operation of physical UGVs through corners has not been examined. Therefore, a better understanding of cornering a teleoperated UGVs is imperative. In Experiment 1, 20 novice participants repeatedly teleoperated a physical UGV using a third-person overhead view through apertures that varied in width. In Experiment 2, 18 additional novice participants completed a similar task but used a first-person view. Participants' performance increased (i.e., faster cornering times and less collisions) over sessions. The cornering law successfully modeled the effect of different aperture widths on participant performance for both viewing perspectives. In this study, we successfully modeled human performance of teleoperated UGVs using the cornering law. Analogous to Fitts' and steering law, we were able to successfully model and predict cornering performance based on a derived index of cornering difficulty. The cornering law could be used to aid in the development of prototype user interfaces and also to examine the effects of different teleoperation views (first person vs. third person).

기동헬기 생존장비 설계 및 입증

Visual information and aural warning of independent aircraft survivability equipment increase the pilot workload and limit the effective countermeasures. For increase the aircraft survivability, Integrated design of survivability display and aural warning need to consider pilot intuitions. If pilot aware the threat by intuition, evade or escape from the threat using the countermeasures equipment, it will increase the survivability. This paper describe the design and verification of for Utility Helicopter survivability equipment.

Making the Mission Computer Intelligent – A Step Ahead

Increasing the complexity of fighter aircraft like modern cockpit environments, covering highly integrated, and complex automatic functions, pose various demands on the crew and adding a heavy workload. Cognitive systems appear to be a promising approach to overcome these deficiencies in future combat aircraft. Developing human-centered automation and designing advanced technology that will capitalize on the relative strengths of humans and machines, are key to the success. This paper presents the approach of applying the artificial intelligence (AI) techniques in the critical mission computer (MC). The mission computer is the central controller of the entire avionics and acts as the front end to the pilot and all other avionic systems by providing all the sensors information, presenting the pilot-vehicle interface and thereby helping a lot in reducing the heavy workload of the pilot. Hence cognitive processing in the MC will make MC to act as an electronic crew assistant sharing the workload of the pilot and helping him in severe situations. Intricate aircraft systems increase the need for intelligent cooperation between pilots and aircraft which will be fulfilled by making the MC as smart or intelligent MC. Defence Science Journal, 2013, 63(2), pp.174 -180 , DOI:http://dx.doi.org/10.14429/dsj. 63.4260

An experimental technique for evaluating the aerodynamic impact of ship superstructures on helicopter operations

Ship–helicopter operating limits for military frigates and destroyers are often restricted in difficult weather conditions because of excessive pilot workload caused by the ship airwake. Despite the importance of the helicopter as a naval tactical system, there is a scarcity of guidance for naval architects with respect to the aerodynamic impact of ship superstructure designs on helicopter operations. This paper describes an experimental investigation into the potential benefits of some aerodynamic modifications to a model-scale generic ship. A model-scale helicopter with a motored main rotor, mounted on a six-axis force balance, has been used to measure the unsteady forces and moments imposed by the airwake. The helicopter has been held, immersed in the unsteady airwakes of a baseline and modified ship geometries, at important locations through the landing approach path for two oblique starboard wind-over-deck angles. Root-mean-square forces and moments have been derived from the time-histories recorded by the force balance. All the ship modifications were found to significantly reduce root-mean-square forces and moments, compared with the baseline ship geometry. Particularly promising design concepts are a side-flap and a notch modification which both showed consistent improvements of 25–50% in root-mean-square loads, in both wind conditions and through various flight paths.

Measuring the Impact of NextGen Operating Concepts for Separation Assurance on Pilot Situation Awareness and Workload

We determined the effect of NextGen concepts of operation for separation assurance on pilot situation awareness and workload using an online probe technique. We also evaluated the probe technique for sensitivity, diagnosticity, and validity with respect to different NextGen separation assurance operating concepts. These concepts allocated responsibility for conflict detection and resolution to either pilots, air traffic controllers, or an automated, ground-based, conflict detection and resolution agent. Probe queries were developed to fit in 1 of 3 categories: traffic conflicts, aircraft or airspace status, or commands and communications. We determined that pilot situation awareness of conflict information was highest when the pilot was responsible for separation assurance; workload was minimally affected. Moreover, the changes in pilot awareness of task-specific information can be determined using this online probe technique. Evidence for the reliability and validity of our probe technique is also provided.

Night Vision Imaging Systems Development, Integration and Verification in MilitaryFighter Aircraft

This paper describes the research and experimental flight testactivities conducted by the Italian Air Force Official Test Centre (RSV) in collaboration with Alenia S.p.A. and Cranfiled University, in order to confer the Night Vision Imaging Systems (NVIS) capability to the Italian TORNADO IDS (Interdiction and Strike) and ECR (Electronic Combat and Reconnaissance) aircraft. The activities included various Design, Development, Test and Evaluation (DDT&E) activities, including Night Vision Goggles (NVG) integration, cockpit instruments and external lighting modifications, as well as various ground test sessions and a total of eighteen flight test sorties. RSV and Litton Precision Products were responsible of coordinating and conducting the installation activities of the internal and external lights. Particularly, an iterative process was established, allowing an in-site rapid correction of the major deficiencies encountered during the ground and flight test sessions. Both single-ship (day/night) and formation (night) flights were performed, shared between the Test Crews involved in the activities, allowing for a redundant examination of the various test items by all participants. An innovative test matrix was developed and implemented by RSV for assessing the operational suitability and effectiveness of the various modifications implemented. Also important was definition of test criteria for Pilot and Weapon Systems Officer (WSO) workload assessment during the accomplishment of various operational tasks during NVG missions. Furthermore, the specific technical and operational elements required for evaluating the modified helmets were identified, allowing an exhaustive comparative evaluation of the two proposed solutions (i.e., HGU-55P and HGU-55G modified helmets). The results of the activities were very satisfactory. The initial compatibility problems encountered were progressively mitigated by incorporating modifications both in the front and rear cockpits at the various stages of the test campaign. This process allowed a considerable enhancement of the TORNADO NVIS configuration, giving a good medium-high level NVG operational capability to the aircraft. Further developments also include the internal/external lighting for the Italian TORNADO “Mid Life Update” (MLU) and other programs, such as the AM-X aircraft internal/external lights modification/testing and the activities addressing low-altitude NVG operations with fast jets (e.g., TORNADO, AMX, MB-339CD), a major issue being the safe ejection of aircrew with NVG and NVG modified helmets. Two options have been identified for solving this problem: namely the modification of the current Gentex HGU-55 helmets and the design of a new helmet incorporating a reliable NVG connection/disconnection device (i.e., a mechanical system fully integrated in the helmet frame), with embedded automatic disconnection capability in case of ejection. Other relevant issues to be accounted for in these new developments are the helmet dimensions and weight, the NVG usable FOV as a function of eye-relief distance, and helmet centre of gravity (moment arms) with and without NVG (impact on aircrew fatigue during training and real operational missions).

Application of Controller Pilot Data Link Communication in the Training for Air Traffic Controller

The application of Controller Pilot Data Link Communication (CPDLC) in the training for air traffic controller is investigated. CPDLC is a data link application that allows for the direct exchange of text-based messages between a controller and a pilot. It greatly improves communication capabilities compared to traditional voice communication, in terms of reducing communication errors and pilot workload, improving the efficiency of airspace management and providing economic benefits. As traffic volume in the airspace becomes saturated, it is necessary to adopt CPDLC as the primary communication method and air traffic controllers should be trained accordingly. In the presented work, the features of CPDLC are introduced as well as the structure of CPDLC system is illustrated, and a novel framework for training air traffic controller with CPDLC system is proposed. It is seen that air traffic controller can be trained with lower workload, fewer mistakes and more flexibility using CPDLC system.

Simulating the environment at the helicopter-ship dynamic interface: research, development and application

AbstractThis paper presents highlights from research conducted at the University of Liverpool to determine suitable fidelity criteria and guidelines for the modelling and simulation of the helicopter-ship dynamic interface environment. The paper begins by describing the characteristics of the helicopter-ship dynamic interface, explaining the motivation behind the research and reviewing the state-of-the-art in dynamic interface simulation. The development of a dynamic interface research environment based on an existing research simulator operated by the University of Liverpool is then described, before key results from a number of piloted simulation experiments are presented. These experiments were specifically designed to address fidelity sensitivity issues, such as, are unsteady airwake models necessary, or can a steady airwake model induce appropriate levels of pilot workload? What influence does the modelled ship geometry, or choice of atmospheric wind conditions have on the airwake model and on pilot workload? Finally, the paper concludes by briefly describing the relevance of these research findings to current and future industry programmes.

A Robust Method for Universal Beacon Code Assignment

This paper describes a method for assignment of beacon codes for secondary surveillance that eliminates the need for code reassignments. The method, Space-Time Adjacency algorithm, assigns unique codes to flights by exploiting the temporal and spatial opportunities in individual flight plans. In simulations of 2007 National Airspace System traffic using this method no reassignments were required. The method is robust for peak day operations in all seasons in the presence of temporal and spatial variations in flight plans. As a result, controller and pilot workload can be reduced, while increasing safety margins.

Effect of Data Communications on Pilot Situation Awareness, Decision Making, and Workload

Over the next decade, the demand for air transportation and other airspace services is expected to grow significantly. To address this, the Federal Aviation Administration (FAA) is developing the Next Generation Air Transportation System (NextGen), which is a series of transformations designed to increase the capacity, safety, and security of air traffic operations. One major enabling technology being investigated is data communications (data comm), which is an electronic text-based message-transferring system between aircraft and ground stations. The literature on data communications outlines both potential benefits and costs. On the benefits side, subject matter experts and researchers have suggested that the switch to text-based communications will lead to reduced distractions and workload (Hoogeboom, Joosse, Hodgetts, Straussberger, & Schaefer, 2004; Navarro & Sikorski, 1999). In addition, data communication is thought to be more accurate and concise (Kerns, 1991; Prinzo, 2001). On the costs side, pilots have reported their belief that loss of information gained through the party line leads to a loss of situation awareness (Prinzo & Campbell, 2008; Hodgetts et al., 2005). Pilots seem particularly concerned with the loss of party line information related to weather, traffic, and holding situations (Pritchett & Hansman, 1997; Pritchett, Midkiff, & Hansman, 1995) and with the loss of information during the busier phases of flight near the airport (Pritchett et al., 1995). However, Boehm-Davis, Gee, Baker, and Medina-Mora (2010) found that while some information presented over the party line is important to pilots’ situation awareness, it may be possible to mitigate the loss of the party line by providing supplemental information with data comm. The purpose of this study was to evaluate the impact of data communications on pilot situation awareness, decision making, and workload. This study built upon a previous study by Boehm-Davis, et al. (2010), which examined party line loss and mitigation strategies. In this study, a two-pilot crew was asked to fly two 40-minute flight scenarios using a low fidelity desktop computer-based flight simulator. The independent variable was communication modality, which was a within-subjects variable. Participants flew one scenario with all communication with air traffic control handled via auditory communication channels. In this condition, they were able to overhear party line communications between other aircraft and ATC. Participants flew the other scenario with all communication with ATC handled via data communications. In this condition, the pilots received clearances from ATC via data comm, and also received data comm messages regarding flight events. Situation awareness and workload were assessed during the flight using the Situation Present Assessment Method (SPAM) (Durso & Dattel, 2004). In this method, participants are interrupted from their primary task with queries about their situation. Accuracy and response time are used as measures of their situation awareness and workload. Subjective workload was measured at the end of each flight, using the NASA-Task Load Index (NASA-TLX) (Hart & Staveland, 1988). Pilot decision making was also assessed. Throughout the experiments, a former airline pilot observed the participants and assessed their awareness, planning, decision making, and actions in response to specific flight events. No significant differences were found for the SPAM workload or situation awareness times or in the number of correct responses to the SPAM situation awareness questions. Likewise, there was no significant difference in subjective workload between conditions, as measured with the NASA-TLX. When presented with specific flight events, participants showed slightly greater awareness, discussion, and action in the data comm condition than in the voice condition. However, this difference was not significant. In addition, pilots were less likely to seek information from ATC in the data comm condition, which could potentially reduce workload for controllers. Although this study did not yield many statistically significant results, the findings imply that there may not be a loss of situation awareness, degradation of decision making, or increase in workload when using data comm instead of voice communications, especially with a well-designed data comm interface, sufficient training, and clear procedures.

UAS Integration into the NAS: An Examination of Baseline Compliance in the Current Airspace System

As a result of the FAA Modernization and Reform Act of 2012, Unmanned Aerial Systems (UAS) are expected to be integrated into the National Airspace System (NAS) by 2015. Several human factors challenges need to be addressed before UAS can safely and routinely fly in the NAS with manned aircraft. Perhaps the most significant challenge is for the UAS to be non-disruptive to the air traffic management system. Another human factors challenge is how to provide UAS pilots with intuitive traffic information in order to support situation awareness (SA) of their airspace environment as well as a see-and-avoid capability comparable to manned aircraft so that a UAS pilot could safely maneuver the aircraft to maintain separation and collision avoidance if necessary. A simulation experiment was conducted to examine baseline compliance of UAS operations in the current airspace system. Researchers also examined the effects of introducing a Cockpit Situation Display (CSD) into a UAS Ground Control Station (GCS) on UAS pilot performance, workload and situation awareness while flying in a positively controlled sector. Pilots were tasked with conducting a highway patrol police mission with a Medium Altitude Long Endurance (MALE) UAS in L.A. Center airspace with two mission objectives: 1) to reroute the UAS when issued new instructions from their commander, and 2) to communicate with Air Traffic Control (ATC) to negotiate flight plan changes and respond to vectoring and altitude change instructions. Objective aircraft separation data, workload ratings, SA data, and subjective ratings regarding UAS operations in the NAS were collected. Results indicate that UAS pilots were able to comply appropriately with ATC instructions. In addition, the introduction of the CSD improved pilot SA and reduced workload associated with UAS and ATC interactions.

Aerodynamic Loading Characteristics of a Model-Scale Helicopter in a Ship's Airwake

Experiments have been conducted in a water tunnel using a specially designed Airwake Dynamometer (AirDyn) to characterize the aerodynamic loading of a helicopter immersed in the airwake of a generic frigate ship. The AirDyn is a 1:54 model-scale helicopter based on a Merlin AW-101, with a six-component force balance mounted inside the fuselage and a simplified spinning main rotor. The AirDyn has been used to measure the unsteady forces and moments imposed by the ship airwake at fixed locations along the flight path of a landing maneuver for a headwind and a 45 wind-angle. A region of ‘thrust-deficit’ in the headwind and a ‘pressure-wall’ in the 45 wind-angle were identified as ‘time-averaged’ loading characteristics caused by spatial velocity gradients in the airwake. The unsteady loading on the AirDyn in the headwind was compared with the 45 case in terms of the severity of the airwake disturbances and the stages of the landing maneuver at which they are significant. The causes of the observed AirDyn loading characteristics have been explained using unsteady Computational Fluid Dynamics analysis of the ship airwakes. The implications of the AirDyn aerodynamic loading characteristics for pilot workload and control input strategies during a real landing are discussed.

Ship-Helicopter Operating Limits Prediction Using Piloted Flight Simulation and Time-Accurate Airwakes

This paper gives an overview of the ship―helicopter dynamic interface simulation facility at the University of Liverpool, with an emphasis on recent improvements made through the inclusion of unsteady computational fluid dynamics (CFD) ship airwake data. A FLIGHTLAB model of an SH-60B Seahawk helicopter has been flown in a full motion base simulator to the deck of a Type 23 frigate and a Wave class auxiliary oiler, under the influence of unsteady airwakes derived from CFD. Pilot workload ratings have been obtained for the deck landing task, using both the Bedford workload rating scale and the deck interface pilot effort scale, from which fully simulated ship―helicopter operating limits have been derived. Analysis of pilot ratings, comments, and control inputs has also enabled both subjective and objective assessments of workloads at various wind-over-deck conditions, highlighting the dominant aerodynamic airwake features which contribute to the difficulty of the landing task. Having access to the underlying CFD data allows the aircraft handling qualities and pilot workload to be correlated with the aerodynamic characteristics of the airwake and identification of the geometric features of the ship that cause them.

Effect of Novel Adaptive Displays on Pilot Performance and Workload

The effect of adaptive display on pilot performance was assessed using objective and subjective measures from a sequence of 2 experiments. Combat aircraft advances have led to dramatic increases in the operational tempo facing the pilot, increasing the likelihood for situation awareness (SA) failures, biases, and information overload. Prior research suggests that adaptive interface might help to address this issue. We designed and evaluated 2 interfaces targeted at problem areas for pilots: a weapons employment zone (WEZ) display designed to support awareness of combat geometry, and an adaptive border display (ABD) designed to warn pilots of impending border infractions breaking rules of engagement. Two experiments were conducted under various levels of scenario complexities to test the ability of these displays to improve SA, reduce workload, and improve objective performance in a population of licensed civilian pilots. Study 1 results showed that the WEZ display significantly improved both performance and SA, and reduced workload. However, there were no significant effects of the ABD. In the second study, we used substantially more complex scenarios to investigate the effect of the ABD. Results showed that in these situations, the ABD had a significant effect on improving pilot performance. The results demonstrate the value of adaptive visualizations that highlight key aspects of the environment that impact performance. Although the results have verified the benefits of adaptive displays, more sensitive performance measures and diverse test pilots are suggested in the future to provide more confidence in applying these findings. Potential application of this research includes modern aircraft cockpit interface design under complex combat scenarios.

Effects of modes of cockpit automation on pilot performance and workload in a next generation flight concept of operation

AbstractThe objective of this study was to compare the effects of various forms of advanced cockpit automation for flight planning on pilot performance and workload under a futuristic concept of operation. A lab experiment was conducted in which airline pilots flew simulated tailored arrivals to an airport using three modes of automation (MOAs), including a control‐display unit (CDU) to the aircraft flight management system, an enhanced CDU (CDU+), and a continuous descent approach (CDA) tool. The arrival scenario required replanning to avoid convective activity and was constrained by a minimum fuel requirement at the initial approach fix. The CDU and CDU+ modes allowed for point‐by‐point path planning or selection among multiple standard arrivals, respectively. The CDA mode completely automated the route replanning for pilots. It was expected that the higher‐level automation would significantly reduce pilot workload and improve overall flight performance. In general, results indicated that the MOAs influenced pilot performance and workload responses according to hypotheses. This study provides new knowledge about the relationship of cockpit automation and interface features with pilot performance and workload in a novel next generation–style flight concept of operation. © 2012 Wiley Periodicals, Inc.

Pilot Performance in Trajectory-Based Operations Under Concepts of Operation That Vary Separation Responsibility Across Pilots, Air Traffic Controllers, and Automation

The Next Generation Air Transportation System (NextGen) will revolutionize the air traffic management system in the United States. NextGen will involve human operators interacting with new technologies in a complex system, making human factors and human–computer interaction considerations a major concern. The present study reports data from a human-in-the-loop simulation that evaluated pilot performance, workload, and situation awareness under one of three plausible NextGen concepts of operation. The concepts of operation differed with respect to the allocation of separation responsibility across human pilots and air traffic controllers (ATCs), and automation. Pilots were asked to employ trajectory-based operations to perform weather avoidance maneuvers, an interval management task, and a continuous descent approach. Depending on the concept being tested, they were also given the responsibility of separation assurance (Concept 1) or received conflict resolutions from an ATC (Concept 2) or automated system (Concept 3). Overall, pilot performance on the various flight tasks was worse in Concept 3 than in Concepts 1 and 2. Although pilot workload did not differ across the three concepts, pilot situation awareness was highest in Concept 1, in which the pilots were given the most responsibilities. These findings suggest that keeping pilots engaged in separation assurance tasks may be preferable to having them rely on automation alone.

Simulator Sickness in Flight Simulators of the German Armed Forces

We investigated simulator sickness in jet simulators without motion platforms (Eurofighter), and in a helicopter simulator (EC 135) as well as in a reconnaissance aircraft simulator (P-3C-Orion) with motion simulation. In addition, workload, visual fatigue, and vitality of pilots were measured. In contrast to jet simulators, where no flashbacks were reported, the EC 135 and the P-3C-Orion simulators proved to be problematic, causing severe simulator sickness symptoms or flashbacks. In all three studies, simulator sickness correlated positively with workload and visual fatigue, while correlating negatively with vitality. In line with previous findings, compared with no-motion simulators, motion-based simulators evoke simulator sickness more easily. Back assumptions that higher workload can reduce simulator sickness could not be proved, since positive correlations were found.

Allocation of Communications to Reduce Mental Workload

As the United States Department of Defense continues to increase the number of Remotely Piloted Aircraft (RPA) operations overseas, improved Human Systems Integration becomes increasingly important. Manpower limitations have motivated the investigation of Multiple Aircraft Control (MAC) configurations where a single pilot controls multiple RPAs simultaneously. Previous research has indicated that frequent, unpredictable, and oftentimes overwhelming, volumes of communication events can produce unmanageable levels of system induced workload for MAC pilots. Existing human computer interface design includes both visual information with typed responses, which conflict with numerous other visual tasks the pilot performs, and auditory information that is provided through multiple audio devices with speech response. This paper extends previous discrete event workload models of pilot activities flying multiple aircraft. Specifically, we examine statically reallocating communication modality with the goal to reduce and minimize the overall pilot cognitive workload. The analysis investigates the impact of various communication reallocations on predicted pilot workload, measured by the percent of time workload is over a saturation threshold.

Recovery Training in Simulator Improves Performance and Psychophysiological State of Pilots During Simulated and Real Visual Flight Rules Flight

This study evaluated an anticipation-based training program for private pilots to recover from unusual flight attitudes, stalls, and spins using visual reference cues. Flight performance, psychophysiological measures of cardiac and electrodermal activity, and subjective measures of workload and emotion were collected from 33 pilots during simulated and real flight. The results demonstrate positive training effects of anticipation-based training in real and simulated flight to improve performance and to change patterns of psychophysiological arousal, workload, and emotion in pilots.