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ObjectiveThe study was designed to investigate whether a simulated unexpected abnormal flight event can lead to startle and explore differences in behavioral responses between expected and unexpected abnormal flight events.BackgroundRecent research suggests startle (an autonomic response to an acute stimulus) following unexpected abnormal flight events can impact pilot performance and can increase the probability of a negative outcome following the event.MethodInformation processing, physiological measures, and performance differences between responses to expected and unexpected flight events were compared. General aviation (GA) pilots flew a series of flights in a fixed-base flight simulator including two experimental flights which included an unexpected and an expected, engine failure. During the flights, heart rate, eye tracking, and flight data were recorded.ResultsDuring the unexpected engine failure, pilots showed greater increases in heart rate and pupil dilation. Significant differences in scanning were evident with fewer areas scanned following the unexpected event. During the unexpected engine failure, performance was impaired when compared to the expected events. However, poor performance was not associated with higher levels of arousal.ConclusionThe study provides an empirical demonstration of impaired pilot response to unexpected events with associated symptoms consistent with the induction of startle. The present research builds on Landman et al.’s conceptual model of startle and surprise.ApplicationStandardized training protocols may not adequately prepare pilots to deal with the unexpected effects of startle in real-world encounters. Introducing greater variety into training events may be useful. The effects of startle in disrupting well-trained responses may also occur in areas other than aviation where critical events may occur unexpectedly or present in an unfamiliar manner.

Objective: This study evaluates the effectiveness of a training program designed to improve cross-functional coordination in airline operations. Background: Teamwork across professional specializations is essential for safe and efficient airline operations, but aviation education primarily emphasizes positional knowledge and skill. Although crew resource management training is commonly used to provide some degree of teamwork training, it is generally focused on specific specializations, and little training is provided in coordination across specializations. Method: The current study describes and evaluates a multifaceted training program designed to enhance teamwork and team performance of cross-functional teams within a simulated airline flight operations center. The training included a variety of components: orientation training, position-specific declarative knowledge training, position-specific procedural knowledge training, a series of high-fidelity team simulations, and a series of after-action reviews. Results: Following training, participants demonstrated more effective teamwork, development of transactive memory, and more effective team performance. Conclusion: Multifaceted team training that incorporates positional training and team interaction in complex realistic situations and followed by after-action reviews can facilitate teamwork and team performance. Application: Team training programs, such as the one described here, have potential to improve the training of aviation professionals. These techniques can be applied to other contexts where multidisciplinary teams and multiteam systems work to perform highly interdependent activities.

Objective: The aim of this study was to understand how the prolonged use of cockpit automation is affecting pilots’ manual flying skills. Background: There is an ongoing concern about a potential deterioration of manual flying skills among pilots who assume a supervisory role while cockpit automation systems carry out tasks that were once performed by human pilots. Method: We asked 16 airline pilots to fly routine and nonroutine flight scenarios in a Boeing 747-400 simulator while we systematically varied the level of automation that they used, graded their performance, and probed them about what they were thinking about as they flew. Results: We found pilots’ instrument scanning and manual control skills to be mostly intact, even when pilots reported that they were infrequently practiced. However, when pilots were asked to manually perform the cognitive tasks needed for manual flight (e.g., tracking the aircraft’s position without the use of a map display, deciding which navigational steps come next, recognizing instrument system failures), we observed more frequent and significant problems. Furthermore, performance on these cognitive tasks was associated with measures of how often pilots engaged in task-unrelated thought when cockpit automation was used. Conclusion: We found that while pilots’ instrument scanning and aircraft control skills are reasonably well retained when automation is used, the retention of cognitive skills needed for manual flying may depend on the degree to which pilots remain actively engaged in supervising the automation.

Objective: The aim of this study was to measure the effects of above-real-time-training (ARTT) speed and screen resolution on a simulated flight control task. Background: ARTT has been shown to improve transfer to the criterion task in some military simulation experiments. We tested training speed and screen resolution in a project, sponsored by Defence Research and Development Canada, to develop components for prototype air mission simulators. Method: For this study, 54 participants used a single-screen PC-based flight simulation program to learn to chase and catch an F-18A fighter jet with another F-18A while controlling the chase aircraft with a throttle and side-stick controller. Screen resolution was varied between participants, and training speed was varied factorially across two sessions within participants. Pretest and posttest trials were at high resolution and criterion (900 knots) speed. Results: Posttest performance was best with high screen resolution training and when one ARTT training session was followed by a session of criterion speed training. Conclusion: ARTT followed by criterion training improves performance on a visual-motor coordination task. We think that ARTT influences known facilitators of transfer, including similarity to the criterion task and contextual interference. Application: Use high-screen resolution, start with ARTT, and finish with criterion speed training when preparing a mission simulation.

Objective: Using the landmark–route–survey frame-work, this research investigated the effect of synthetic vision systems (SVS) in either low or high visibility conditions on performance in wayfinding and spatial-knowledge-based tasks that probed spatial awareness. Background: SVS are cockpit displays that depict computer-generated views of the terrain surrounding an aircraft and have been developed to support flight efficiency through improved spatial awareness. No studies have directly measured SVS impact on the three levels of spatial knowledge (landmark, route, and survey). Method: A total of 55 nonpilots learned a route in four different experimental conditions (high or low visibility, either with or without SVS). Subsequently, they underwent four recall tasks: wayfinding, scene recognition, scene classification, and sketch map. Six dependent measures were used to probe the three levels of spatial knowledge (selection errors, sorting errors, number of landmarks depicted, bidimensional regression) and their use in the wayfinding task (direction errors, designated landmark errors, and wayfinding verbalized hesitations). Results: SVS produced higher performance in all four tasks. The low visibility condition lowered the wayfinding and scene-recognition performance. Conclusion: The overall results indicated that visibility mostly affected the first level of spatial knowledge (landmark) inducing a decreased wayfinding performance, whereas the use of SVS influenced the three levels of spatial knowledge (route and survey) inducing an increased wayfinding performance. Application: Potential applications of this work include spatial knowledge-based measures to evaluate SVS prototypes as well as to assess the relationship between spatial knowledge and spatial awareness.

Objective: This study investigated whether stress training introduced during the acquisition of simulator-based flight skills enhances pilot performance during subsequent stressful flight operations in an actual aircraft.Background: Despite knowledge that preconditions to aircraft accidents can be strongly influenced by pilot stress, little is known about the effectiveness of stress training and how it transfers to operational flight settings.Method: For this study, 30 participants with no flying experience were assigned at random to a stress-trained treatment group or a control group. Stress training consisted of systematic pairing of skill acquisition in a flight simulator with stress coping mechanisms in the presence of a cold pressor. Control participants received identical flight skill acquisition training but without stress training. Participants then performed a stressful flying task in a Piper Archer aircraft.Results: Stress-trained research participants flew the aircraft more smoothly, as recorded by aircraft telemetry data, and generally better, as recorded by flight instructor evaluations, than did control participants.Conclusions: Introducing stress coping mechanisms during flight training improved performance in a stressful flying task.Application: The results of this study indicate that stress training during the acquisition of flight skills may serve to enhance pilot performance in stressful operational flight and, therefore, might mitigate the contribution of pilot stress to aircraft mishaps.

Objective: This study (a) compares the effectiveness of different types of feedback for novices who learn to land a virtual aircraft in a fixed-base flight simulator and (b) analyzes the informational variables that learners come to use after practice. Background: An extensive body of research exists concerning the informational variables that allow successful landing. In contrast, few studies have examined how the attention of pilots can be directed toward these sources of information. Method: In this study, 15 participants were asked to land a virtual Cessna 172 on 245 trials while trying to follow the glide-slope area as accurately as possible. Three groups of participants practiced under different feedback conditions: with self-controlled concurrent feedback (the self-controlled group), with imposed concurrent feedback (the yoked group), or without concurrent feedback (the control group). Results: The self-controlled group outperformed the yoked group, which in turn outperformed the control group. Removing or manipulating specific sources of information during transfer tests had different effects for different individuals. However, removing the cockpit from the visual scene had a detrimental effect on the performance of the majority of the participants. Conclusion: Self-controlled concurrent feedback helps learners to more quickly attune to the informational variables that allow them to control the aircraft during the approach phase. Applications: Knowledge concerning feedback schedules can be used for the design of optimal practice methods for student pilots, and knowledge about the informational variables used by expert performers has implications for the design of cockpits and runways that facilitate the detection of these variables.

Objective: The Implicit Association Test (IAT), in combination with a battery of additional psychometric tests, was employed to examine the accuracy with which it predicts pilots’ risk-taking behavior. Background: Risk management is an integral part of piloting. Many factors affect pilots’ risk management, including individual differences. Therefore, employing a unique methodology from social cognition, the present study examined the influence of attitude, as measured implicitly through the IAT, personality, and flight experience variables on pilots’ risk-taking behavior. Method: In addition to a simulated flight on a computer-based flight simulator, 35 pilots completed a battery of psychometric tests. Results: Among the 6 risk perception variables, 10 risk attitude variables, and 2 experience variables, only 2 variables were found to be significantly related with in-flight risk-taking behavior: everyday risk (risk perception) and the IAT effect (attitude). Of these, the IAT effect was the strongest predictor of flight behavior. Conclusion: The results indicate that implicit attitudinal measures, such as the IAT, provide a more accurate forecast of pilot behavior than do the more traditional explicit attitudinal or personality measures. Application: An implicit attitudinal measure can be proactively employed to identify pilots who are potentially more likely to engage in high-risk activities, hence permitting a more strategic approach to pilot training.

Objective: We investigated expertise differences in pilot decision making by examining a hypothesized attention-action link. During simulated flight we measured the accuracy and latency of more and less expert pilots' decision outcomes and used eye tracking to measure their attention. We also examined whether decision outcomes and attentional strategies were influenced by properties of the cues indicating problems. Background: Errors in decision making contribute to many accidents and incidents, especially among inexperienced pilots. Although much is known about decision errors in terms of their outcomes, less is known about the cognitive processes that underlie expert differences in aviation decision making. Method: Fourteen more expert and 14 less expert pilots flew 16 flights in a simulator. Half of the flights contained a failure requiring diagnosis and action in response to the failure. Cues signaling the failures varied in how diagnostic and/or correlated they were. Results: The more expert pilots generally made better decisions in terms of speed and accuracy. Both groups made faster correct decisions when cues were high versus low in diagnosticity. Only the more expert pilots made faster correct decisions when cues were correlated. More attention was allocated to relevant cues (measured by percentage dwell time on areas of interest) when a failure was present, primarily among expert pilots. Moreover, the amount of attention to cues was associated with decision accuracy. Conclusion: The findings support the link between greater attention and more effective decision making. Application: The expert advantage in attention underlying decision outcomes may provide targets for improving pilot training.

Objective: To examine operator strategies for diagnosing and recovering from errors and disturbances as well as the impact of automation design and time pressure on these processes. Background: Considerable efforts have been directed at error prevention through training and design. However, because errors cannot be eliminated completely, their detection, diagnosis, and recovery must also be supported. Research has focused almost exclusively on error detection. Little is known about error diagnosis and recovery, especially in the context of event-driven tasks and domains. Method: With a confederate pilot, 12 airline pilots flew a 1-hr simulator scenario that involved three challenging automation-related tasks and events that were likely to produce erroneous actions or assessments. Behavioral data were compared with a canonical path to examine pilots' error and disturbance management strategies. Debriefings were conducted to probe pilots' system knowledge. Results: Pilots seldom followed the canonical path to cope with the scenario events. Detection of a disturbance was often delayed. Diagnostic episodes were rare because of pilots' knowledge gaps and time criticality. In many cases, generic inefficient recovery strategies were observed, and pilots relied on high levels of automation to manage the consequences of an error. Conclusion. Our findings describe and explain the nature and shortcomings of pilots' error management activities. They highlight the need for improved automation training and design to achieve more timely detection, accurate explanation, and effective recovery from errors and disturbances. Application: Our findings can inform the design of tools and techniques that support disturbance management in various complex, event-driven environments.

Objective: The objective of the study was to examine pilots' automation monitoring strategies and performance on highly automated commercial flight decks. Background: A considerable body of research and operational experience has documented breakdowns in pilot-automation coordination on modern flight decks. These breakdowns are often considered symptoms of monitoring failures even though, to date, only limited and mostly anecdotal data exist concerning pilots' monitoring strategies and performance. Method: Twenty experienced B-747-400 airline pilots flew a 1-hr scenario involving challenging automation-related events on a full-mission simulator. Behavioral, mental model, and eye-tracking data were collected. Results: The findings from this study confirm that pilots monitor basic flight parameters to a much greater extent than visual indications of the automation configuration. More specifically, they frequently fail to verify manual mode selections or notice automatic mode changes. In other cases, they do not process mode annunciations in sufficient depth to understand their implications for aircraft behavior. Low system observability and gaps in pilots' understanding of complex automation modes were shown to contribute to these problems. Conclusion: Our findings describe and explain shortcomings in pilot's automation monitoring strategies and performance based on converging behavioral, eye-tracking, and mental model data. They confirm that monitoring failures are one major contributor to breakdowns in pilot-automation interaction. Application: The findings from this research can inform the design of improved training programs and automation interfaces that support more effective system monitoring.

Objective: Two experiments were conducted in which participants navigated a simulated unmanned aerial vehicle (UAV) through a series of mission legs while searching for targets and monitoring system parameters. The goal of the study was to highlight the qualitatively different effects of automation false alarms and misses as they relate to operator compliance and reliance, respectively. Background: Background data suggest that automation false alarms cause reduced compliance, whereas misses cause reduced reliance. Method: In two studies, 32 and 24 participants, including some licensed pilots, performed in-lab UAV simulations that presented the visual world and collected dependent measures. Results: Results indicated that with the low-reliability aids, false alarms correlated with poorer performance in the system failure task, whereas misses correlated with poorer performance in the concurrent tasks. Conclusion: Compliance and reliance do appear to be affected by false alarms and misses, respectively, and are relatively independent of each other. Application: Practical implications are that automated aids must be fairly reliable to provide global benefits and that false alarms and misses have qualitatively different effects on performance.

Two experiments conducted in a high-fidelity flight simulator examined the effects of guidance symbology, display size, and geometric field of view (GFOV) within a synthetic vision system (SVS). In Experiment 1, 18 pilots flew highlighted and low-lighted tunnel-in-the-sky displays, as well as a less cluttered follow-me aircraft (FMA), through a series of curved approaches over rugged terrain. The results revealed that both tunnels supported better flight path tracking and lower workload levels than did the FMA because of the availability of more preview information. Increasing tunnel intensity had no benefit on tracking and, in fact, degraded traffic awareness because of clutter and attentional tunneling. In Experiment 2, 24 pilots flew a lowlighted tunnel configured according to different display sizes (small or large) and GFOVs (30 degrees or 60 degrees). Measures of flight path tracking and terrain awareness generally favored the 60 degrees GFOV; however, there were no effects of display size. Actual or potential applications of this research include understanding the impact of SVS properties on flight path tracking, traffic and terrain awareness, workload, and the allocation of attention.

In the first part of the reported research, 12 instrument-rated pilots flew a highfidelity simulation, in which air traffic control presentation of auditory (voice) information regarding traffic and flight parameters was compared with advanced display technology presentation of equivalent information regarding traffic (cockpit display of traffic information) and flight parameters (data link display). Redundant combinations were also examined while pilots flew the aircraft simulation, monitored for outside traffic, and read back communications messages. The data suggested a modest cost for visual presentation over auditory presentation, a cost mediated by head-down visual scanning, and no benefit for redundant presentation. The effects in Part 1 were modeled by multiple-resource and preemption models of divided attention. In the second part of the research, visual scanning in all conditions was fit by an expected value model of selective attention derived from a previous experiment. This model accounted for 94% of the variance in the scanning data and 90% of the variance in a second validation experiment. Actual or potential applications of this research include guidance on choosing the appropriate modality for presenting in-cockpit information and understanding task strategies induced by introducing new aviation technology.

Two experiments examined pilots' maneuver choice and visual workload in a free-flight simulation. In Experiment 1, 12 pilots flew a high-fidelity flight simulator with a cockpit display of traffic information and maneuvered to avoid traffic in a simulated free-flight environment. Pilots' choices reflected a preference to make vertical rather than lateral avoidance maneuvers and to climb rather than descend. Pilots avoided both complex maneuvers and airspeed maneuvers. The data were modeled in terms of how pilots traded off factors related to safety, efficiency, mental effort, and prior habits. In Experiment 2, 10 pilots flew the same maneuvers as the pilots in Experiment 1 but followed ATC instructions rather than using the CDTI. The CDTI in Experiment 1 occupied 25% of the pilots' visual attention. A comparison of scanning with Experiment 2 suggested that the CDTI pulled visual attention away from the outside world, but this attention diversion did not leave pilots vulnerable to missing traffic not annunciated on the CDTI. Actual or potential applications of the results include understanding the safety implications of presenting traffic displays in the cockpit, and the impact of pilot maneuver preferences on airspace procedures.

Visual flight rules (VFR) flight into instrument meteorological conditions (IMC) is a major safety hazard in general aviation. In this study we examined pilots' decisions to continue or divert from a VFR flight into IMC during a dynamic simulation of a cross-country flight. Pilots encountered IMC either early or later into the flight, and the amount of time and distance pilots flew into the adverse weather prior to diverting was recorded. Results revealed that pilots who encountered the deteriorating weather earlier in the flight flew longer into the weather prior to diverting and had more optimistic estimates of weather conditions than did pilots who encountered the deteriorating weather later in the flight. Both the time and distance traveled into the weather prior to diverting were negatively correlated with pilots' previous flight experience. These findings suggest that VFR flight into IMC may be attributable, at least in part, to poor situation assessment and experience rather than to motivational judgment that induces risk-taking behavior as more time and effort are invested in a flight. Actual or potential applications of this research include the design of interventions that focus on improving weather evaluation skills in addition to addressing risk-taking attitudes.

Novel patterns of visual-vestibular intersensory stimulation often result in symptoms of simulator sickness, raising health and safety concerns regarding virtual environment exposure. Two experiments investigated the effect of conflicting visual-vestibular cues on subjective reports of simulator sickness during and after a 30-min exposure to a head-coupled virtual interface. Virtual image scale factors (0.5, 1.0, 2.0 magnification, generated by varying geometric field of view angle) were investigated in Experiment 1, and additional system time delays (125, 250 ms) were investigated in Experiment 2. Simulator sickness metrics included spoken self-reports during exposure and simulator sickness questionnaires (pre-exposure, immediate postexposure, and 20 min postexposure). Head yaw angular position data were also recorded. Reports of simulator sickness symptoms were significantly greater in the minification (0.5) and magnification (2.0) image scale factor conditions than in the neutral condition (1.0). Simulator sickness did not vary with changes in time delay, however. Furthermore, a comparison across experiments suggests no appreciable increase in simulator sickness with increasing time delays above the nominal value (48 ms). Head angular position data exhibited certain systematic variations across conditions. Actual or potential applications of this research include virtual environment training, simulation, and entertainment systems.

A flight simulator and a computer-generated depiction of an environment with both natural and cultural features were used to teach and test navigation knowledge. Conditions of guided rehearsal, unguided rehearsal, and map study were used to familiarize participants with the navigation environment. A subsequent route-following test of navigation knowledge in the simulated environment showed that unguided rehearsal was better than map study or guided rehearsal for the development of route knowledge. In addition, a pointing task revealed that unguided mission rehearsal was as good as map study for the development of survey knowledge. Actual or potential applications of this research include the use of simulator-based mission rehearsal for military flight operations.

The effects of adaptive task allocation on monitoring for automation failure during multi task flight simulation were examined. Participants monitored an automated engine status task while simultaneously performing tracking and fuel management tasks over three 3D-min sessions. Two methods of adaptive task allocation, both involving temporary return of the automated engine status task to the human operator (“human control”), were examined as a possible countermeasure to monitoring inefficiency. For the model-based adaptive group, the engine status task was allocated to all participants in the middle of the second session for 10 min, following which it was again returned to automation control. The same occurred for the performance-based adaptive group, but only if an individual participant's monitoring performance up to that point did not meet a specified criterion. For the nonadaptive control groups, the engine status task remained automated throughout the experiment. All groups had low probabilities of detection of automation failures for the first 40 min spent with automation. However, following the lO-min intervening period of human control, both adaptive groups detected significantly more automation failures during the subsequent blocks under automation control. The results show that adaptive task allocation can enhance monitoring of automated systems. Both model-based and performance-based allocation improved monitoring of automation. Implications for the design of automated systems are discussed.

The effectiveness of a three-dimensional (3D) auditory display in conveying directional information was investigated in a flight simulation experiment. While flying a simulated fighter aircraft, participants followed a target aircraft that suddenly disappeared and reemerged at an unknown position. The task was to locate and trail the target as quickly as possible. In all conditions the participants viewed a computer-generated outside image, on which they could spot the target only when it was at short range, and a three-dimensional (3D) tactical display indicating the target position at all distances within a limited field of view. Additional displays were a bird's-eye-view radar display, which also indicated whether the target was above or below the own plane, and a 3D auditory display, which generated a warning sound from the relative direction of the target. The auditory display used individualized head-related transfer functions to create a virtual sound source and a head-tracking device to decouple the position of the source from head movements. Results show that the radar and auditory displays caused about the same significant reduction in search time in comparison with the tactical display only. A further reduction was found when the two additional displays were presented simultaneously.

The advantage of a head-up auditory display was evaluated in a preliminary experiment designed to measure and compare the acquisition time for capturing visual targets under two auditory conditions: standard one-earpiece presentation and two-earpiece three-dimensional (3D) audio presentation. Twelve commercial airline crews were tested under full mission simulation conditions at the NASA Ames Man-Vehicle Systems Research Facility advanced concepts flight simulator. Scenario software generated visual targets corresponding to aircraft that would activate a traffic collision avoidance system (TCAS) aural advisory; the spatial auditory position was linked to the visual position with 3D audio presentation. Results showed that crew members using a 3D auditory display acquired targets approximately 2.2 s faster than did crew members who used one-earpiece headsets, but there was no significant difference in the number of targets acquired.

The results of research conducted in ground-based flight simulators must be interpreted with care in view of the potential effects of differences between the simulated and actual flight environments. A study comparing various flight-director displays in a moving-base simulator was replicated without motion. Significantly different results occurred as a function of the presence or absence of motion. Implications of these results raise doubt concerning the validity of findings from simulator experiments in which whole-body acceleration cues might be a factor.

Previous research has indicated that components of the event-related potential (ERP) may be used to quantify the resource requirements of complex cognitive tasks. The present study was designed to explore the degree to which these results could be generalized to complex, real-world tasks. The study also examined the relations among performance-based, subjective, and psychophysiological measures of operator workload. Seven male volunteers, enrolled in an instrument flight rule (IFR) aviation course at the University of Illinois, participated in the study. The student pilots flew a series of IFR flight missions in a single-engine, fixed-based simulator. In dual-task conditions subjects were also required to discriminate between two tones differing in frequency and to make an occasional overt response. ERPs time-locked to the tones, subjective effort ratings, and overt performance measures were collected during two separate 45-min flights differing in difficulty. The difficult flight was associated with high subjective effort ratings, as well as increased deviations from the command altitude, heading, and glideslope. The P300 component of the ERP discriminated among levels of task difficulty, decreasing in amplitude with increased task demands. Within-flight demands were examined by dividing each flight into four segments: takeoff, straight and level flight, holding patterns, and landings. The amplitude of the P300 was negatively correlated with deviations from command headings across the flight segments. In sum, the findings provide preliminary evidence for the assertion that ERP components can be employed as metrics of resource allocation in complex, real-world environments.

This report was initiated to review the techniques and modifications developed by the U.S. Army Aeromedical Research Laboratory for assessing visual performance/workload of pilots during helicopter operations. Although the corneal reflection technique for gathering eye movement data is not new, innovative modifications had to be developed to permit accurate data collection in this flight environment. This study reports on these techniques, modifications, and applications.

Tests were conducted to determine the significance of vertical acceleration cues in the simulation of the visual approach and landing maneuver. Landing performance measures were obtained for four subject pilots operating a visual landing simulation mechanized in the Ames Height Control Test Apparatus, a device that provides up to plus or minus 40 ft of vertical motion. Test results indicate that vertical motion cues are utilized in the landing task, and that they are particularly important in the simulation of aircraft with marginal longitudinal-handling qualities. To assure vertical motion cues of the desired fidelity in the landing task, it appears, that a simulator must have excursion capabilities of at least 20 ft in either direction.