Development Study for a Helipad Standard Marking Pattern

The report presents the results in the development of a recommended marking pattern for helipads. The objective of the study was to determine the marking pattern which would best fulfill requirements which were established on the basis of current practices, discussions with helicopter pilots, and helicopter operational observations. Field tests were conducted following laboratory observations and scale-model studies. Those requirements which most influenced final selection of the marking pattern were (1) Visual Flight Rules conditions (daytime), (2) recognition of the pattern from one mile, and (3) a five-degree minimum approach angle. Elements of pattern size and contrast gained significance as a result of field test evaluation. In order that the selected pattern most effectively meet the requirements, minimum overall pattern size and line width were recommended. Also, to emphasize the importance of good contrast, it was recommended that the marking pattern be white, edged with a black border unless the surface is sufficiently dark that the border is not needed for good contrast. The selected pattern was recommended as an Army standard for helipad marking and, in addition, is being considered as a national and international standard.