Read Full Report

Date: Feb. 18, 1998
Contacts: Dan Quinn, Media Relations Officer
Sean McLaughlin, Media Relations Assistant
(202) 334-2138; e-mail <>


Human Capacity Must Be Central Consideration
In Automation of Air Traffic Control System

WASHINGTON -- The Federal Aviation Administration (FAA) should not give pilots greater control over their routes until the agency can demonstrate that the plan would be safe, according to a new report from a panel of the National Research Council. The plan, known as "free flight," is one consideration in a large modernization and automation effort being pursued by the FAA. The report says that all decisions about what to automate should be guided by the need to compensate for human vulnerabilities and exploit human strengths, rather than by the desire to use new technology.

"Automation and free flight could help the FAA create a more reliable and efficient system, increase capacity in the air, and minimize delays caused by poor weather and inefficient routes," said panel chair Christopher Wickens, head of the Aviation Research Laboratory, University of Illinois, Urbana-Champaign. "However, before any major changes are made to the air traffic control system, it is crucial that we test the way pilots and controllers would respond to the new demands being placed on them."

The panel examined a range of automation and modernization plans at the FAA, including free flight and a host of new technologies to help air traffic controllers manage the air space. All are intended to help the agency cope with pressures from an ever-growing number of flights and outdated equipment. The panel's report, The Future of Air Traffic Control: Human Factors and Automation, concludes that current needs and available technology justify automation in some areas, but says that human capacities must be a central consideration.

FAA first should focus on automation that would aid in acquiring, integrating, or presenting information for controllers on the ground to use in making decisions, the report says. New technology to help controllers resolve conflicts in the air, keep proper spacing in the final stages of approach to landing, and change routes to improve efficiency will be especially needed as skies grow more crowded. The FAA should pursue high levels of automation only for decisions and actions that involve relatively little uncertainty and risk, such as tracking the weather. Final decisions for high-risk tasks should still be made by ground-based personnel.

Congested Skies

Efforts to make flights more efficient -- such as free flight -- are backed by commercial air carriers, for whom even short delays from poor weather or crowded skies can mean large financial losses. Free flight would take advantage of existing and emerging technologies designed to provide pilots with more real-time information about airborne hazards and wind and weather patterns, and help them gain more efficiency in their flight plan. Proposed scenarios vary in the degree to which pilots or ground-based controllers have control. In either scenario, however, pilots would have some control over their own flight path, the report says.

Moving control from the ground to the air, however, could make it more difficult for the ground-based controllers to maintain an accurate mental picture of the airspace. Control should remain with personnel on the ground until the safety implications of free flight are well understood, the report says.

The panel called on FAA to conduct extensive simulation studies of free flight in order to examine what is likely to happen in a range of scenarios. The agency should test some free flight concepts through extensive simulations and focus-group sessions with controllers, pilots, traffic managers, and airline dispatchers. Lingering uncertainties remain over in-flight negotiations between pilots, how pilots would react to their increased work load and decision-making responsibility, how to maintain controllers' alertness to hazards in an airspace, and how to resolve possible confusion over who has authority among air traffic controllers, pilots, and airline operations personnel.

On the ground, tasks that require decisions to be made, or which involve some amount of uncertainty or risk, should not be automated beyond simply suggesting actions for human operators, the report says. Especially when automation limits the controller's options, it is critical that a human operator is able to review the recommendations made by automated systems before deciding what to do.

When considering automating a task more fully, the FAA should design systems that guard against eroding a controller's vigilance or skill level, or hamper the current level of teamwork and communication among controllers. Operators must be able to assume control in the case of system failures, and be able to maintain safe separation of planes. And FAA should work to make sure all new designs are compatible with the current system, rather than simply "tacked on" as new technology is developed. Human factors experts should be involved from design to implementation, the report says.

A panel roster follows. The National Research Council is the operating arm of the National Academies of Sciences and Engineering. It is a private, non-profit organization that provides advice on science and technology. This study was sponsored by the U.S. Department of Transportation.

Read the full text of The Future of Air Traffic Control: Human Operators and Automation for free on the Web, as well as more than 1,800 other publications from the National Academies. Printed copies are available for purchase from the National Academy Press Web siteor at the mailing address in the letterhead; tel. (202) 334-3313 or 1-800-624-6242. Reporters may obtain a pre-publication copy from the Office of News and Public Information at the letterhead address (contacts listed above).