Graduate assistant in physics Ohio University, 1965—1967, research assistant in acoustics, 1967—1968. Associate engineer transducer laboratory General Dynamics/Electronics Company, Rochester, New York, 1968—1969, engineer acoustics department, 1969—1971. National Aeronautics and Space Administration trainee Pennsylvania State University, 1971—1974, graduate assistant in acoustics, 1974—1980.
Staff associate Applied Research Laboratory, State College, Pennsylvania, 1976—1980. Technical staff marine system division Rockwell International, Groton, Connecticut, 1980—1984. Senior scientist Bolt Beranch & Newman, New London, 1984—1987.
Physicist Navigation Underwater System Center, since 1987.
Fellow: National Aeronautics and Space Administration. Member: American Association for the Advancement of Science, American Institute of Aeronautics and Astronautics, Pennsylvania State University Alumni Association (alumni council and executive board 1973-1974), New York Academy of Sciences, United States Othello Association (Midwestern Othello champion 1979, corporation director 1979-1984), American Contract Bridge League (president local club 1970-1971), American Go Association, American Cryptographic Association, Acoustical Society of America, National Speleological Society (life. Vice chairman Nittany Grotto 1975-1976), United States Chess Federation (captain Pennsylvania State University team 1973, tournament director), Sigma Pi Sigma (national delegate 1967), Kappa Mu Epsilon, Sigma Xi.