High-Speed Video Observations of Downward Negative Lightning Attachment to Tall Structures at the Kennedy Space Center

Abstract:
High speed video observations of downward negative lightning strikes that terminated on tall structures at the Kennedy Space Center in Florida are presented with particular emphasis on the time period of the attachment process. Close observations of aborted, unconnected, and connecting upward positive leaders from tall structures are reported and analyzed. Upward leader characteristics are analyzed as functions of structure height and geometry. Finally, the high-speed video data are used to perform measurements of the striking distance for lightning strikes to tall structures. These measurements are compared with those calculated using common IEC recommended formulation.