Triggered lightning strokes at very close range

The inability to predict the point of strike of natural lightning flashes to ground makes it very difficult to carry out repeated measurements under reasonably reproducible conditions. This difficulty has been overcome to some extent by measurements on discharges to high buildings, radio towers, power lines, and other fixed structures. During the last several years we have experimented with long wires carried aloft by rockets to induce strokes from overhead thunder-clouds. These strokes will be referred to as triggered lightning strokes. Early experiments with the schooner Azara [Newman, 1958, 1965] have been continued with our research vessel R. V. Thunderbolt in the vicinity of St. Petersburg, Florida. During August 1966, of 23 attempts 17 cloud-vessel lightning flashes were successfully triggered.