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Segal, Leon D.

Publications and source records attributed to Segal, Leon D..

Effects of checklist interface on non-verbal crew communications

The investigation looked at the effects of the spatial layout and functionality of cockpit displays and controls on crew communication. Specifically, the study focused on the intra-cockpit crew interaction, and subsequent task performance, of airline pilots flying different configurations of a new electronic checklist, designed and tested in a high-fidelity simulator at NASA Ames Research Center. The first part of this proposal establishes the theoretical background for the assumptions underlying the research, suggesting that in the context of the interaction between a multi-operator crew and a machine, the design and configuration of the interface will affect interactions between individual operators and the machine, and subsequently, the interaction between operators. In view of the latest trends in cockpit interface design and flight-deck technology, in particular, the centralization of displays and controls, the introduction identifies certain problems associated with these modern designs and suggests specific design issues to which the expected results could be applied. A detailed research program and methodology is outlined and the results are described and discussed. Overall, differences in cockpit design were shown to impact the activity within the cockpit, including interactions between pilots and aircraft and the cooperative interactions between pilots.

Segal, Leon D.↗

Activity Catalog Tool (ACT) user manual, version 2.0

This report comprises the user manual for version 2.0 of the Activity Catalog Tool (ACT) software program, developed by Leon D. Segal and Anthony D. Andre in cooperation with NASA Ames Aerospace Human Factors Research Division, FLR branch. ACT is a software tool for recording and analyzing sequences of activity over time that runs on the Macintosh platform. It was designed as an aid for professionals who are interested in observing and understanding human behavior in field settings, or from video or audio recordings of the same. Specifically, the program is aimed at two primary areas of interest: human-machine interactions and interactions between humans. The program provides a means by which an observer can record an observed sequence of events, logging such parameters as frequency and duration of particular events. The program goes further by providing the user with a quantified description of the observed sequence, through application of a basic set of statistical routines, and enables merging and appending of several files and more extensive analysis of the resultant data.

Segal, Leon D.↗

Automation design and crew coordination

Advances in technology have greatly impacted the appearance of the modern aircraft cockpit. Where once one would see rows upon rows. The introduction of automation has greatly altered the demands on the pilots and the dynamics of aircrew task performance. While engineers and designers continue to implement the latest technological innovations in the cockpit - claiming higher reliability and decreased workload - a large percentage of aircraft accidents are still attributed to human error. Rather than being the main instigators of accidents, operators tend to be the inheritors of system defects created by poor design, incorrect installation, faulty maintenance and bad management decisions. This paper looks at some of the variables that need to be considered if we are to eliminate at least one of these inheritances - poor design. Specifically, this paper describes the first part of a comprehensive study aimed at identifying the effects of automation on crew coordination.

Segal, Leon D.↗

TASKILLAN II - Pilot strategies for workload management

This study focused on the strategies used by pilots in managing their workload level, and their subsequent task performance. Sixteen licensed pilots flew 42 missions on a helicopter simulation, and were evaluated on their performance of the overall mission, as well as individual tasks. Pilots were divided in four groups, defined by the presence or absence of scheduling control over tasks and the availability of intelligence concerning the type and stage of difficulties imposed during the flight. Results suggest that intelligence supported strategies that yielded significant higher performance levels, while scheduling control seemed to have no impact on performance. Both difficulty type and the stage of difficulty impacted performance significantly, with strongest effects for time stresss and difficulties imposed late in the flight.

Segal, Leon D.↗