have been recognized, and new team training efforts (discussed below) have been initiated in air traffic control.

The nature of team communication breakdowns can be illustrated by describing several accidents in which the controller-pilot interface was identified as a contributory element, either positive or negative. Research into input and group process factors associated with incidents also contributes to an understanding of the team role.

The 1972 crash of a wide-bodied jet transport in the Florida Everglades provided an early look at flawed communication between an air traffic controller and a flight crew as well as the impact of distractions on flight crew performance (National Transportation Safety Board, 1973). In this accident, the cockpit crew became distracted from primary flying and monitoring duties while investigating a landing gear warning light. During this period, the autopilot was inadvertently disengaged and the aircraft began a gradual descent from its intended altitude. The controller on duty did not warn the crew in any way of its impending flight into terrain—but merely asked ''how are things going out there?" In the cockpit there was a failure to maintain active monitoring of flight controls and in air traffic control there was a failure to share situation awareness that could have prevented the accident.

In contrast with the preceding accident, at Sioux City in 1989, the handling of a DC-10 that lost all hydraulic systems and flight controls due to the catastrophic failure of an engine was exemplary (National Transportation Safety Board, 1990). During the in-flight emergency, the flight crew worked effectively with controllers to select an alternate airport and to mobilize emergency units prior to the attempted landing. In this emergency, there was appropriate exchange of information both within the flight deck and between the pilots and the air traffic controllers, and this was combined with sensitivity to workload issues and emotional support needs (Predmore, 1991). The flight crew attributed their successful management of the emergency to formal training in interpersonal human factors known as crew resource management.

In 1990 a B-707, en route from Medellin, Colombia, crashed near New

FRONT MATTER (R1-R14)

EXECUTIVE SUMMARY (1-14)

1 OVERVIEW (15-31)

2 TASKS IN AIR TRAFFIC CONTROL (32-53)

3 PERFORMANCE ASSESSMENT, SELECTION, AND TRAINING (54-75)

4 AIRWAY FACILITIES (76-88)

5 COGNITIVE TASK ANALYSIS OF AIR TRAFFIC CONTROL (89-111)

6 WORKLOAD AND VIGILANCE (112-134)

7 TEAMWORK AND COMMUNICATIONS (135-151)

8 SYSTEMS MANAGEMENT (152-176)

9 HUMAN FACTORS IN AIRWAYS FACILITIES (177-196)

10 STRATEGIES FOR RESEARCH (197-225)

11 HUMAN FACTORS AND SYSTEM DEVELOPMENT (226-240)

12 AUTOMATION (241-289)

REFERENCES (290-336)

Appendix A Aviation and Related Acronyms (337-342)

Appendix B Contributors to the Report (343-344)

Appendix C Biographical Sketches (345-352)

INDEX (353-368)