Why are the lightning towers around launch pads topped with big hollow tubes with spiral windings? Why not conventional lightning rods - big metal rods with pointy things at the top?
Possibly related: https://electronics.stackexchange.com/q/410152/102305
Cropped and recklessly sharpened from NASA Spaceflight
Screenshot from this video
Above: The first piece of Pad 39B to be removed, the 80-foot lightning mast that topped the fixed service structure (FSS), was lowered on March 3, 2009. NASA's first launch pad lightning protection mast, it was used for the 1975 Apollo-Soyuz Test Project (ASTP) before being adapted for the space shuttle program. Photo: NASA/Amanda Diller