David L. Cooper, 84, a retired Navy captain who worked on shipboard electronics for technology and defense contractors including Sperry and Unisys, died Jan. 17 at a hospital in Viera, Fla.

He had Alzheimer’s disease, his son Brian Cooper said.

Capt. Cooper lived in McLean and Vienna for several decades before moving to Florida in the late 1990s.

During a nearly three-decade-long military career, Capt. Cooper sailed in the Arctic and across the Equator. His assignments included postings in the Pacific and in Washington, where he worked on naval security and communications before his military retirement in 1979. Before his retirement from the private sector in the mid-1990s, he led a joint project by Raytheon and General Electric related to naval communications and radar.

David Lawson Cooper was born in Newark. He received a bachelor’s degree in mechanical engineering from Rensselaer Polytechnic Institute in Troy, N.Y., in 1950 and a master’s degree in electrical engineering from the Naval Postgraduate School in Monterey, Calif.

His military decorations included the Meritorious Service Medal.

Capt. Cooper was a former Boy Scouts troop leader in Northern Virginia, and he did volunteer work with the U.S. Coast Guard Auxiliary and with heart patients at Inova Fairfax Hospital. His memberships included the Sons of the American Revolution, the Masons, Shriners International, and Toastmasters International. His hobbies included square-dancing and model railroads.

His first marriage, to Eunice Kling, ended in divorce.

Survivors include his wife of 29 years, Mary Kiser Young Cooper of Viera; five children from his first marriage, Marti Lindsey of Tucson, Betsy Dere of Wattle Glen, Australia, Jon Cooper of Middlebourne, W.Va., Brian Cooper of Manassas and Callie Ryan of Hagerstown, Md.; two stepchildren, Colin Young of Woodbridge and Leslie Wayment of Melbourne, Fla.; a sister; 11 grandchildren; and a great-granddaughter.

— Emily Langer