Abstract
During the development of the Small Unmanned Aircraft Systems rule under Part 107 in Title 14 of the Code of Federal Regulations, the Federal Aviation Administration reported that they do not have any data that would indicate what color, if any, would enhance the conspicuity of small unmanned aircraft. By definition, conspicuity is the quality or state of being conspicuous or how easily it can be seen or noticed. A meta-analysis of archival data determined that fluorescent red-orange color schemes would most effectively increase the conspicuity of small unmanned aircraft to help establish and maintain unaided visual contact (other than corrective lenses and sunglasses) by ground operators/visual observers and pilots of manned aircraft under day visual meteorological conditions. The use of fluorescent paint schemes on airplane and rotorcraft type small unmanned aircraft, irrespective of their size, increased the visibility, detectability, range, and conspicuity. Fluorescent paint schemes were qualitatively ranked first and had a mean detection range of 2.16 miles versus a 1.0 mile range for non-fluorescent enamel paint schemes. Civil Aviation Authorities should consider the use of fluorescent colors in the development of future regulations and requirements.
