Michael E. Trenchard

Searching in clutter: Visual attention strategies of expert pilots

Clutter can slow visual search. However, experts may develop attention strategies that alleviate the effects of clutter on search performance. In the current study we examined the effects of global and local clutter on visual search performance and attention strategies. Pilots and undergraduates searched for an elevation marker in charts of high, medium, and low global clutter. The target was in a low or high local clutter region of the chart or it was absent. High global and local clutter slowed search performance for both pilots and undergraduates. Pilots were more accurate but slower. Pilots’ search strategies differed from undergraduates in the following ways: they had more conservative criteria for responding target absent and spent more time processing the information within each fixation. Pilots and undergraduates used a coarse-to-fine search strategy in which, as the trial progressed, fixation durations increased and saccade distance decreased.

Human Factors Issues in Advanced Moving-map Systems

Vector-based maps are an advanced capability of digital moving-map systems that are easily customised and can be powerful aids to aircrew information processing and decision-making, However, they may place excessive demands on an aircrews information processing requirements, cause an increase in workload, and degrade situational awareness if the user interface is not designed properly. There is little information available about the human factors and situational awareness issues relevant to vector-based maps. In this paper, we summarise relevant research on human factors and situational awareness aspects of using vector-based maps identify key issues, anti recommend directions for future research.

Pilot Preferences on Vector Moving-Map Displays

Vector map databases offer the potential for customised cockpit moving-map displays, in which user-specified cartographic features can be layered to meet mission requirements. The disadvantage of vector moving-maps is the potential for increased user workload, In 1995. the Naval Research Laboratory and the Naval Air Weapons Center jointly performed a preference study, during which aircrew viewed demonstrations of prototype moving-map displays and responded to a detailed questionnaire concerning the usefulness of each display This paper summarises aircrew interviews from that study pertaining to both vector moving-map displays and vector feature overlays, including Height-Above-Threshold (HAT), threat rings, and Clear Line-of-Sight (CLOS).

Human Factors Issues in the Development of an Advanced Digital Moving Map System

The U.S. Navy is currently sponsoring a Tactical Aircraft Moving Map Capability (TAMMAC) program that will provide the standard cockpit digital moving map system for Naval Aviation. The TAMMAC system will be used by a variety of Navy aircraft with differing operational needs and resources and can be tailored to meet aircraft-specific operational requirements. A major design goal of the TAMMAC program is to increase mission effectiveness and situation awareness without further burdening pilot workload. Human factors engineering (HFE) specialists from the government and industry have played an important role in the execution of the TAMMAC program throughout all phases. This paper provides examples of the contributions HFE specialists have made to the program, discusses baseline and planned growth capabilities of the TAMMAC digital map computer, discusses human factors issues regarding these capabilities, and identifies future research needs.