Sehchang Hah

Cognitive Workload and Learning Assessment During the Implementation of a Next-Generation Air Traffic Control Technology Using Functional Near-Infrared Spectroscopy

Neuroimaging technologies, such as functional near-infrared spectroscopy (fNIR), could provide performance metrics directly from brain-based measures to assess safety and performance of operators in high-risk fields. In this paper, we objectively and subjectively examine the cognitive workload of air traffic control specialists utilizing a next-generation conflict resolution advisory. Credible differences were observed between continuously increasing workload levels that were induced by increasing the number of aircraft under control. In higher aircraft counts, a possible saturation in brain activity was realized in the fNIR data. A learning effect was also analyzed across a three-day/nine-session training period. The difference between Day 1 and Day 2 was credible, while there was a noncredible difference between Day 2 and Day 3. The results presented in this paper indicate some advantages in objective measures of cognitive workload assessment with fNIR cortical imaging over the subjective workload assessment keypad.

Human Performance Assessment Study in Aviation Using Functional Near Infrared Spectroscopy

Functional near infrared (fNIR) spectroscopy is a field-deployable optical neuroimaging technology that provides a measure of the prefrontal cortex’s cerebral hemodynamics in response to the completion of sensory, motor, or cognitive tasks. Technologies such as fNIR could provide additional performance metrics directly from brain-based measures to assess safety and performance of operators in high-risk fields. This paper reports a case study utilizing a continuous wave fNIR technology deployed in a real-time air traffic control (ATC) setting to evaluate the cognitive workload of certified professional controllers (CPCs) during the deployment of one of the Federal Aviation Administration’s (FAA’s) Next Generation (NextGen) technologies.

Human-in-the-Loop Simulation Experiment of Integrated Arrival/Departure Control Services For NextGen Operational Improvement

The National Airspace System suffers from a reduction in airport throughput or even closure when weather or traffic volume constrains arrival or departure gates to and from the Terminal Radar Approach Control (TRACON) facilities. To alleviate this, the Federal Aviation Administration introduced the Integrated Arrival and Departure Control Services (IADCS) concept that would extend terminal separations and procedures to the adjacent Air Route Traffic Control Center (ARTCC) sectors for more flexible traffic. It proposes the use of resectorization, bidirectional gates, bidirectional routes, and Air Traffic Control assigned routes. We evaluated them in the human-in-the-loop high-fidelity experiment and collected objective and subjective data. Our results clearly showed that all IADCS procedures except the vertically separated/bidirectional gate procedure were more effective than the Baseline condition that controllers currently use in the field. We conjecture the vertically separated/bidirectional gate procedure requires more complex perceptual and cognitive processes than the other procedures.

The relationship between aircraft count and controller workload in different en route workstation systems

Some air traffic control researchers have reported that the relationship between aircraft count in the sector and controller workload is nonlinear. Other researchers have reported it linear. However, they did not manipulate the number of aircraft separately in their experiments. In our experiment, we gradually increased traffic levels within each experimental run. Our controllers used three different workstation systems with and without data communication. The linear and power models described the relationship well. The proportion of workload variance explained by aircraft count was well above 50%. With these models, we predict controllers could handle about four (13%) more aircraft with data communication than without it with the Display System Replacement (DSR) system that is currently used at Air Route Traffic Control Centers (ARTCCs).

Human Factors Evaluation of Conflict Resolution Advisories for Air Traffic Control in the En Route Domain

In this paper, we report results of a human-in-the-loop simulation experiment that evaluated how Conflict Resolution Advisories (CRA) affected en route air traffic controllers’ performance. Twelve current en route Certified Professional Controllers from Air Route Traffic Control Centers (ARTCCs) participated in the experiment. Results showed that controllers used CRA menus significantly more often than Baseline menus. They also spent more time interacting with the CRA menus than with the Baseline menus. Most of the participants’ subjective ratings favored the CRA, but they also pointed out a few features to be improved.

Evaluation of the impact of data communications on controller workload using the functional near infra red imaging technique

• FAA William J. Hughes Technical Center • NextGen • Data Communications • En Route Automation Modernization System • En Route Data Communications Experiment • Workload Assessment Keypad • Functional Near Infra Red Spectography • Workload Results • Discussion

Prototyping an En Route Data Communications human computer interface

• FAA William J. Hughes Technical Center • NextGen • Data Communications • En Route Automation Modernization System • En Route Data Communications Experiment • Prototyping Approach • Discussion Discussion • prototype to create a functional environment to evaluate requirements • design decisions are always a compromise of many alternatives • balance requirements of individual technologies, but integrate them at the user interface

Evaluation of the impact of data communications equipage level on air traffic controller workload using the functional near infra-red imaging technique

The Federal Aviation is modernizing the National Airspace System to accommodate an anticipated growth and diversification of air traffic. Several technologies are necessary to move from the current air traffic control system to the Next Generation Air Transportation System (NextGen). One of these technologies, Data Communications, will move the air traffic control system from a mostly voice-based communications environment to a digital environment. In this digital environment, voice-based communications will still be in use for time-critical situations, but text-based communications will be available for most other situations. Such a drastic shift in operations potentially poses technical challenges and human factors issues. Technical challenges include the need to design highly reliable systems that allow controllers to rely on the availability of the Data Comm system while providing an acceptable response time. Human factors challenges include the integration of Data Comm messaging in controller tasks, the provision of more information without creating clutter, and providing more automation without increasing workload or reducing situation awareness. In earlier studies, we found that the availability of a high percentage of Data Comm equipped aircraft in the en route environment resulted in a large reduction of subjective workload even at high traffic levels. In the current study we manipulated the percentage of equipped aircraft at constant traffic levels to determine if the reduction in workload is present at other equipage levels. We collected subjective workload ratings and physiological measures of cognitive workload.

Human factors considerations in prototyping an En Route Data Communications Human Computer Interface

Data Communications is one of the enablers necessary for the realization of the Next Generation Air Transportation System. The need to incorporate Data Communications into existing systems results in a large number of requirements and design decisions. One way to validate requirements and mitigate risks of design decisions is to prototype an implementation of the requirements. The prototype environment can then serve as a platform to demonstrate the capabilities to operational personnel and to compare design alternatives during informal evaluations or formal Human-In-The-Loop (HITL) experiments. To prepare for a high fidelity HITL experiment that investigated several aspects of En Route Data Communications, we prototyped a Human Computer Interface that extended our emulation of the En Route Automation Modernization system. We reused existing display artifacts where possible and introduced new display objects and functions where needed. We present several examples of design decisions made during this process.

What Happens When Data Communication Fails? - A Simulation Study

One of the key enabling technologies required to achieve the Federal Aviation Administration’s (FAA’s) Next Generation Air Transportation System (NextGen) goals is Data Communication (Data Comm) between controllers and pilots. It reduces voice communication congestion and errors. A concern about Data Comm is that it can fail. Our en route simulation experimental results showed that controllers talked with pilots more frequently after failure compared to the same scenario without failure. Workload also increased, but the difference was not statistically significant. We did not find any significant increase in the frequencies of clearances issued after failure. The participant controllers responded that partial and system failures were detrimental to their performance. They commented that the aircraft failure symbol needed to be more pronounced and that they would need help after partial and total system failures in heavy traffic. We present recommendations to alleviate the problems from Data Comm failure.