Richard C. Brackney, who spent more than 30 years as a senior engineer at the National Security Agency, died Sept. 12 at Johns Hopkins Hospital in Baltimore. He was 75.

The cause was complications after a heart attack in May, said his wife, Marianne Brackney.

Mr. Brackney, who lived in Columbia, dealt with cybersecurity research and development at the NSA. He received two National Defense Service Medals and a Meritorious Service Medal before his retirement in 2010.

Richard Conrad Brackney was born in Northampton, Mass. He was a 1960 graduate of Norwich University in Vermont, then served three years in the Army.

He remained in the Army Reserve and served as an operations officer during the Persian Gulf War in the early 1990s. He retired from the reserves as a colonel in 1998.

He received a master’s degree in administration of research and development management in 1974 and a master’s degree in engineering in 1980, both from George Washington University. He also attended the Army’s Command and General Staff College, and he held a pilot’s license.

Before joining the NSA in 1979, Mr. Brackney worked for Westinghouse Electric. After retiring from the NSA, he worked for Microsoft.

His first marriage, to Ines Davis, ended in divorce.

Survivors include his wife of 31 years, Marianne Hyang Nam Brackney of Columbia; their son, Timothy S. Brackney of Ellicott City; two children from his first marriage, Seni Brackney McDonnell of Fulton, Md., and Ricky Brackney of Gaithersburg; two sisters; and a brother.

— Bart Barnes