The experiment of artificial lightning triggered with a rocket pulling up the grounded wire has been carried out since 1977 in cooperation with the following members ; I. Miyachi, K. Horii, Y. Kito, H. Akiyama, H. Yamashita, Y. Higashiyama (Nagoya Univ.), S. Muto, K. Nakamura (Nagoya Inst. of Tech.), G. Ikeda, S. Sumi (Chubu Inst. of Tech.), S. Aiba (Kanazawa Inst. of Tech.), R. Ishibashi (Kanazawa Univ.), H. Sakurano (Ishikawa Tech. College) and N. Kitagawa (Saitama Univ.). The purposes of this experiment are to investigate the mechanism of the lightning discharge including predischarge phenomena, and to develop the technique protecting from the hazards by lightning discharge. Though the lightning has not been triggered in summers, 32 lightnings were triggered in winters at Hokuriku, the north coast of Japan. The peak value and the duration of discharge current, the electric field intensity at ground, the altitude of rocket, and others were measured, and the relations among them were discussed. The mechanism of lightning discharge was made clear from the optical observation and the measurement of current. The long gap discharges between the bobbin hanging in air and the ground were successfully performed three times, and the hairpin effect of mannequin and the safety in a motorcar for the lightning discharge were confirmed. The surge voltages induced on the test line of power distribution were measured and the shielding effect of the overhead grounded wire to the test line was confirmed. At last, the subjects to be investigated are described with the conclusion of this paper.
Kenji Horii (Sat,) studied this question.