FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute

Report No: DOT/FAA/AM-14/9

Title and Subtitle: A Review of Research Related to Unmanned Aircraft System Visual Observers

Report Date: October 2014

Authors: Williams KW, Gildea KM

Abstract: This paper is a review of human factors research that is related to the task of the visual observer in unmanned aircraft system (UAS) operations. Primarily, visual observers are used to assist in the prevention of a mid-air collision during the course of a UAS operation. Therefore, much of the research reviewed is related to ground-based visual observation of aircraft. The research covers basic human visual system capacity and limitations, visual performance models, and empirical studies of visual observation. The empirical studies include visual observer studies, aircraft see-and-avoid research, and search and rescue operations research.

The results from this research are compared with current visual observer requirements to show where some of the requirements might exceed the capacity of the visual observer to perform adequately. The final section of the document presents recommendations and suggested guidelines for the UAS operations that use visual observers. In addition to their use in avoiding mid-air collisions with aircraft, visual observers can be used to assist the UAS pilot in avoiding difficult to see obstructions such as power lines and guy wires. Observers can also be used to monitor the movements of people and vehicles that might stray too close to an operation. Readers who are not interested in details of the research are encouraged to skip to the guidelines section.

Key Words: Unmanned Aircraft, Visual Observer, Small UAS Operations, UAV, Drone

No. of Pages: 23