Fairchild Industries Inc. said yesterday that Emanuel Fthenakis has been elected president and chief operating officer of the aerospace and electronics conglomerate.

Fthenakis, 57, had served as an executive vice president and succeeds Edward G. Uhl, 67, who retains the titles of chairman and chief executive officer.

Fthenakis had supervised Fairchild's communications, electronics and space operations, "considered by the company to be potentially the greatest growth area of its business," said a statement released by the Chantilly-based firm.

A native of Greece who is now a U.S. citizen, Fthenakis joined Fairchild in 1971 and became a vice president that year. In 1972, he founded and became president of American Satellite Co., which is 50 percent owned by Fairchild.

In 1976, he became a senior vice president of Fairchild and in 1984 was elected an executive vice president. He became a director in 1985.

Fthenakis graduated from Columbia University, worked for Bell Laboratories and later moved to General Electric's space division. Between 1962 and 1969, he founded, organized and directed the Philco-Ford space division and "was responsible for developing the first U.S. military communications satellite system," according to Fairchild.

He was appointed by President Reagan to the National Security Telecommunications Advisory Council. He is the author of "A Manual of Satellite Communications" and is an adjunct professor at the University of Maryland, teaching a graduate course in space and communications technology.