Evaluating the relationship between data resolution and the accuracy of identified helicopter landing zones (HLZs)

Helicopters provide critical advantages in military operations because of their ability to land at small and unimproved sites. While the military uses models to identify helicopter landing zones (HLZs), little research has been conducted on their accuracy. This study evaluated the performance of an HLZ detection model derived from existing selection criteria that incorporated elevation and land cover data with spatial resolutions ranging from 1 m to 30 m. Multiple HLZs were selected as study sites at three geographically varied locations. The HLZ boundaries identified using the derived model were then compared to surveyed reference boundaries to assess their accuracy. This study found that as the spatial resolution of the data became coarser, accuracy decreased across all sites. However, there were some instances where noticeable increases in error were observed at certain resolutions for some sites. The resolution at which this occurred was always related to the size of features either bounding or located within the landing area. Thus, this study found that the most important consideration when determining ideal resolution for HLZ detection is the geography of the study area. While additional research is needed, this study presents initial findings and a framework upon which future assessments can build.