A New-Model Rocket for Artificially Triggering Lightning and Its First Triggering Lightning Experiment

The new-model rocket for artificially triggering lightning was developed recently in China, and the body of the rocket is made of composite material and is light in weight. The new rockets and new measurement techniques of current and the corresponding electromagnetic fields were used in Shandong Artificially Triggering Lightning Experiment in the summer of 2009 (SHATLE2009), and three negative lightning discharges from cloud to ground, containing six subsequent return strokes, were successfully triggered in the experiment. The waveforms of discharge current were documented with 0.1-μs time resolution by using the new coaxial shunt with a resistant of 0.5 mΩ which output was transmitted to a 16-channel digital oscilloscope for recording through a broad band optical fiber. The corresponding electromagnetic fields at 30 m, 60 m, and 480 m away were measured simultaneously. The peak current of six subsequent return strokes ranged from 11.2 to 16.3 kA with a geometric mean value of 12.8 kA. The half peak width ranged from 7.4 to 34.9 μs with a geometric mean value of 21.6 μs. The rise time from 10% to 90% peak ranged from 0.5 to 1.4 μs with a geometric mean value of 1.0 μs. The successful triggering lightning experiment confirmes that the rocket with wire-trailing function is reliable and safe, and the parachute assembled inside the rocket shows good performance. The new-developed rocket for triggering lightning provides a crucial tool not only for the study of lightning and its effects, but also for the data accumulation of lightning current waveforms which is essential to the lightning protection design.