McConnell was born in Pennsylvania in 1914, and studied at Carnegie Institute of Technology obtaining a B.S.
Naval aircraft factory and at the Massachusetts Institute of Technology Radiation Laboratory.
He also worked in radar moving target indication, iconoscope, and ultrasonic microwaves.
McConnell was the first president of the Parapsychological Association and a Fellow of the American Psychological Society.
He was Research Professor Emeritus of Biological Sciences at the University of Pittsburgh.