In the control room, facing a complex array of radar screens and computer displays, air traffic controllers manage the movement of hundreds of planes, issuing clearances and instructions intended to speed traffic flow and ensure safety. Overhead, airplane pilots scan the multitude of dials and gauges that line the cockpit, keeping a watchful eye out the window and a steady hand on the controls. These controllers and pilots are key players in a complex system of air traffic management. At either end, they rely on the information provided by their screens, displays, dials, and gauges, as much as they do on their own seasoned intuition and the operational procedures. The nexus of this complex system is the verbal communication between controllers and pilots communication that must be ordered, efficient, and precise.
Who designs this system? Engineers perfect the accuracy of radar receivers (computer programmers develop the algorithms that process a multitude of data), and the Federal Aviation Administration makes rules that govern air traffic control. Meanwhile, someone must ensure that pilots and controllers are operating in a work environment that contributes to safety and efficiency. The displays must show all the necessary information in a "user friendly" fashion; the alerts and warnings that flash and beep must be noticeable, but not distracting; communication protocols should be straightforward and orderly; and the psychological demands of the job cannot exceed the limitations of the people performing it. These "human factors" aspects are key components of successful work environments. Fortunately for all of us who fly in airplanes, these systems are the main focus of the work of Dr. Kim Cardosi, Senior Researcher at the Volpe Center, and international expert in the design and evaluation of air traffic control systems.
In order to improve system efficiency and reduce error, Kim analyzes all aspects of the air traffic control environment, from the color of warning lights to the amount of information in controllers' instructions. To these observations she applies her detailed scientific understanding of human perception, a deep appreciation for the complexities of flying and air traffic control, and a keen sense of how humans interact. She studies the physical and psychological abilities that affect job performance (How quickly does the eye perceive a warning light? How many different pieces of information can a person remember from one verbal communication?) and makes sure that the system is compatible with those abilities. "My job is to try to figure out all the possible mistakes a person can make and what the consequences of those errors would be," she explains. Once she understands the potential errors involved in a system or work environment, she can work with engineers and designers to produce systems (such as radar displays and communication protocols) that minimize the potential for design-induced error.
In 1985, Kim earned her Ph.D in Experimental Psychology from Brown University. Her many years of research had given her a detailed understanding of human perception but less of an idea of where to apply that expertise. She knew that she wanted to apply her knowledge to real-world issues that had human relevance, but she had little idea of what that might involve. During her final year of school a professor recommended she attend the Annual Meeting of the Human Factors Society with a view to finding a potential job. Kim was initially skeptical. At the time, the potential applications of human factors research had not yet been fully explored, and the field was not widely applied to aviation.
Kim quickly learned that Human Factors was an opportunity to use her specialized knowledge of perception in practical applications. She found the opportunity she'd hoped for at the Transportation Systems Center (not yet the Volpe Center), where she could apply her knowledge of perception and attention to activities on the flight deck.
As it turns out, her detailed knowledge of psychology was just what the Volpe Center needed. After thirteen years, Kim is one of the Center's senior human factors researchers. She has become a nationally-recognized expert in the field, and her findings are applied to air traffic control exchanges every day. Her recent 700-page manual, Human Factors in the Design and Evaluation of Air Traffic Control Systems, is treated as a bible by many in the field. As a mother of three whose family has first priority, she has, over the years, reshaped the image of the traditional transportation engineer. In between her work at the Volpe Center and across the country, she has earned a private pilot's license. She maintains a strong enthusiasm for her job and the contributions she makes to air safety.
Defined broadly, Human Factors is the discipline that applies the knowledge of human capabilities and limitations (both physical and psychological) to the design of technological systems. Kim makes it a priority to understand the work environment of air traffic control and to experience first hand how people operate under those conditions. But how does one study the communications between pilots and air traffic controllers without interfering with their work? Fortunately for Kim's research, audio tapes record every word spoken between the cockpit and the air traffic facilities. However tedious, Kim has made it a point to listen to many hours of these recordings, studying the order in which instructions are issued, the ways that pilots and controllers acknowledge each other, and how such factors can influence miscommunications. Since substantive communication errors between pilots and controllers are extremely rare (less than one percent of transmissions) this type of research doesn't provide much "bang for the buck" when it comes to examining serious communication breakdowns. Fortunately, Kim can also turn to the Aviation Safety Reporting System, in which pilots and controllers describe communication errors that had the potential to threaten the safety of a flight. Even more importantly, the ASRS gives pilots and controllers the opportunity to describe their perceptions of a miscommunication and voice their ideas about how it could have been avoided.
Kim is also eager to describe aspects of her research that allow her to get away from her desk. In order to understand how flight and cabin crews work together in emergency situations, Kim attended cabin crew emergency training. Her experiences there, opening emergency doors exiting the aircraft in simulated smoke, helped her devise more efficient coordination procedures for cockpit and cabin crews. These recommendations, developed in 1988, won her the Research and Special Programs Administrator's Award for Superior Achievement.
Kim enjoys her opportunities to work directly with air traffic controllers and pilots, because she says she "always learns something." Every air traffic facility is a little different. This makes the task of designing systems and tools even more difficult because what works for some controllers may not be what's best for other controllers. Her painstaking review of transmission recordings, her countless hours of sitting in the cockpit jump seat and visiting ATC facilities, her numerous interviews with controllers and pilots all this to develop a comprehensive understanding of the air traffic control environment. It is this understanding that has earned her respect among controllers. During a discussion about the potential effects of an application of new technology, an air traffic controller looked Kim in the eye and said, with surprise, "You really understand my job, don't you?"
"I don't pretend to know everything about being an air traffic controller, but it was one of the best compliments I've ever received." commented Kim.
Among all the research into perception, short-term memory, and cognitive ability, there is a diplomatic aspect to Kim's work that focuses on the complex relationship between pilots and air traffic controllers. A controller must safely coordinate the movements of all planes within his or her airspace; this effort requires that each plane perform exactly as the controller instructs and expects. On the other hand, a pilot is solely responsible for the safety of his or her aircraft and its passengers, and may choose to overrule a controller's instructions if they could endanger the plane. Effective communication will continue to be critical to ensure flight safety, as new technology is introduced and regulations loosen to provide pilots with more flexibility. Kim is working with NASA, and others on a study that examines what will be needed to make this increased flexibility a reality. Another area of Kim's job that requires diplomacy is asserting the importance of imposing high standards in human factors support for system design while recognizing the importance of impacts to development costs and schedules. Human factors specialists are still unpopular in many circles since they are the people who identify potential problems that the program offices wish didn't exist. Still, it is widely recognized that it is wise to make the initial investment in human factors in the beginning of a program. By teaming human factors specialists with engineers and the potential users of a system, potential problems can be identified early when they are easier and less costly to fix. In the end, it costs less to attend to human factors issues than to ignore them. "Human Factors is a little like preventive maintenance. You can pay me now (to identify and prevent potential problems) or you can pay me later (to "fix" the system). Later always costs more."
