Born in Pueblo, Colorado, Hyman graduated from the United States Naval Academy in 1924. He first served in battleship USS New Mexico (BB-40), and in the years before World War II, was assigned to many ships and a variety of shore stations, including the Office of Naval Operations. He assumed command of destroyer USS Sims (DD-409) 6 October 1941. After convoy escort duty in the Atlantic, Sims moved to the Pacific in early 1942.
In May, as the Japanese attempted to extend their conquest to Port Moresby, the ship was operating with oiler USS Neosho (AO-23) in a fueling group for Admiral Frank Jack Fletcher's aircraft carriers. While the carrier fleets maneuvered for position, Japanese planes found Neosho and Sims in the Coral Sea; and, thinking they were carrier and escort, attacked in strength. After Lt. Comdr. Hyman fought his ship through 2 air raids with great skill, 36 Japanese planes attacked the 2 ships. Sims took three 500-lb. bomb hits in this third attack. From the time the first bomb that hit the Sim's had exploded to the time she was sunk was a total of 48 seconds, leaving only 13 survivors. The sacrifice of his ship and Neosho had much to do with saving the Navy's carriers in the widely separated engagements known as the Battle of the Coral Sea. The Japanese blunder in mistaking the Sims for a cruiser and the flat top Neosho as an American carrier, diverted much needed air power and other resources from the Battle of Midway, just a few days away. As the Sims was sinking, with all but the forward 5" gun submerged, the Sims continued to fire her gun even though the gun crew knew they were about to die. The actions of Commander Hyman and his crew were upholding the finest traditions of the U.S. Navy. Lieutenant Commander Hyman received the Navy Cross for his heroic service.
USS Hyman (DD-732) was named for him.
- Ainsworth, D. L. (July 8, 1942). "Destroyers, Pacific Fleet: Sinking of the U.S.S. SIMS (DD-409) by Japanese Bombers in the Coral Sea on May 7, 1942" (Memorandum). United States Navy. Retrieved 2008-11-06. (Primary source)
- Dicken, Robert James (May 18, 1942). "Personal observations of SIMS #409 disaster" (Memorandum). United States Navy. Retrieved 2008-11-06. (Primary source)
- Hoyt, Edwin Palmer (2003). Blue Skies and Blood: The Battle of the Coral Sea. I Books. ISBN 0-7434-5835-4.
- Morison, Samuel Eliot (2001) . Coral Sea, Midway and Submarine Actions, May 1942–August 1942, vol. 4 of History of United States Naval Operations in World War II. Champaign, Illinois, USA: University of Illinois Press. ISBN 0-252-06995-1.