Nuclear pioneer Edwin Kintner, who helped develop a reactor for the first U.S. atomic-powered submarine, died at age 90 in Exeter, N.H., his family said.

Kintner died May 7 of prostate cancer, his son Eric told The New York Times in a story published Friday.

Edwin Kintner worked on reactor technology used to power the Nautilus, the first U.S. atomic submarine, which had its maiden voyage Jan. 17, 1955.

"To produce Nautilus, it was necessary to expand man's knowledge far beyond the 'known' in almost every technical area - physics, metallurgy, mechanical engineering, electronics, environmental medicine," Kintner wrote in an article for The New York Times Magazine in 1965.

Kintner also worked for the Atomic Energy Commission, was head of the U.S. Department of Energy's fusion program and was named to oversee the cleanup when the reactor core failed at the Three Mile Island nuclear station near Harrisburg, Pa., in March 1979.

Kintner was born in Paris, Ohio, graduated from the U.S. Naval Academy and earned masters' degrees in naval construction, ocean engineering and physics at the Massachusetts Institute of Technology.

Besides his son Eric, of Westford, Mass., he is survived by his wife, Alice, of Exeter, N.H.; sons John of Fort Lauderdale, Fla., and Peter, of Park City, Utah; and daughter, Mary, of Underhill, Vt.