Karl B. McEachron

Karl B. McEachron
Karl B. McEachron
Hoosick Falls, NY, USA
Death date
Associated organizations
General Electric (GE)
Fields of study
Power, Lightning
AIEE Edison Medal


Karl Boyer McEachron was born in Hoosick Falls, NY, 17 November 1889, son of John Henry and Dora (Peters) McEachron. McEachron graduated with degrees in E.E. and M.E. from Ohio Northern University in 1913 and M.S. at Purdue University in 1920, respectively. In 1914, he began his career at the Pittsfield (Mass.) plant of the General Electric Co., and from 1914 to 1918 he was an instructor in electrical engineering at Ohio Northern University. He was an instructor in electrical engineering and research assistant and then associate in the Engineering Experiment Station at Purdue University from 1918 to 1922. From 1922 until his retirement he was associated with the General Electric Co. in Pittsfield, Mass. He was head of the research and development section in the lightning arrester department from 1922 to 1933, and in the latter year was made research engineer in charge of high-voltage engineering. He became assistant works engineer in 1945 and was design engineer in the power transformer engineering division during 1940 to 1945, assistant manager of engineering, 1945 to 1949, and manager of engineering from 1919 to 1953.

High-voltage engineering work was initiated at General Electric by Charles P. Steinmetz and carried on by Frank W. Peek. McEachron was responsible for the practical application of a number of laboratory methods to specific problems in the field. It was the purpose of the high-voltage laboratories, established in 1914, to test insulators and other protective apparatus used on high-tension transmission lines in order to discover the means of protecting lines and power-houses from damage in electrical storms. Under McEachron's direction the first cathode ray oscillograms of the performance of lightning arresters were taken in 1923. He made the first field investigation of the effect of a portable lightning generator on a high- voltage transmission line in 1929, and he investigated the traveling wave theory, using a portable impulse generator (1,500,000 volts) and cathode ray oscillograph. This study of the behavior of waves of electrical energy on lines and in cables was the most thoroughgoing attempted up to the time. An investigation with similar apparatus, made in 1931 on the lines of the Associated Gas & Electric Co. examining the effect of lightning discharges on distribution transformers, had a profound influence on the development of protection practices, particularly as applied to so-called interconnection.

Another of McEachron's achievements was the consummation of work begun by Steinmetz and others, namely the development of an impulse generator that could duplicate the effect of natural lightning. In 1934 he completed such a generator delivering 260,000 amperes, discharging at the comparatively low potential of 150,000 volts, producing an energy discharge at a rate of more than 30,000,000 kilowatts, the nearest approach to a natural lightning discharge produced in the laboratory up to that time. Subsequently McEachron engaged in a study of the mechanism of the lightning discharge, with particular reference to the multiple stroke. As many as forty discharges from cloud to earth and from earth to cloud were photographed in the same path and within one second, and the most damaging discharge proved to be the upward stroke from earth to cloud. McEachron made the first known oscillograms of direct lightning strokes simultaneously recorded on motion picture film, and disclosed a type of lightning bolt called the continuous stroke, an arc between a cloud and the earth, persisting in some cases for a full one-half second or more. He was able to record lesser strokes that made little or no thunder, and strokes in which the leader was directed upward from the earth were also photographed. He was the designer of the spectacular show of man-made lightning at the New York World's Fair in 1939-40, where he doubled the voltage of the 5,000,000-volt stroke of artificial lightning that split tree-trunks at Pittsfield, Mass., in 1936. In 1949, at the dedication of a new General Electric high-voltage laboratory in Pittsfield, he raised the power to 15,000,000 volts flashing across a fifty-foot gap between two generators. He had also been called upon in 1938 to advise New York City officials on protecting swimmers from lightning at the city's beaches.

While at Purdue during World War I, McEachron conducted research on the fixation of atmospheric nitrogen by the silent discharge method. He developed a material called Thyrite (LT.S. Pat. No. 1,822,742), 1931, which had the property of being substantially an insulator when low voltages were applied and of becoming automatically a relatively low-resistance conductor when high voltages were applied. The material found wide application in lightning arresters and in control circuits.

McEachron was author of a number of published papers dealing with atmospheric nitrogen and with protection of lines and apparatus and flux distribution in transformers. He received the Coffin Award of the General Electric Co. in 1931, the Longstreth Medal of the Franklin Institute in 1935, and the Edison Medal of the American Institute of Electrical Engineers in 1949 "For his contributions to the advancement of electrical science in the field of lightning and other high voltage phenomena and for the application of this knowledge to the design and protection of electric apparatus systems." At the New York World's Fair in 1940 he received the B. F. Goodrich Award for distinguished service in the field of lightning research. He also received an honorary D.Eng. degree from Ohio Northern University in 1938 and an honorary D.Sc. degree from Purdue University in 1941. For ten years McEachron served on the Massachusetts State Board of Registration for Engineers. He was a fellow of the American Institute of Electrical Engineers and a member of the Indiana Academy of Science, Sigma Xi, and the Pittsfield Rotary Club.

He was married 28 August 1914, to Leila Emily Honsinger, and they had five children: Karl Boyer, William Donald, Gertrude Louise, Robert Earle, and Alice Claire. He died in Pittsfield, Mass. on 24 January 1954.