Welkin was a 23rd century Human man who served in Starfleet and was assigned to the Federation starship USS Enterprise in 2285. In that year, Welkin was one of the survivors of the battle with Khan Noonien Singh's USS Reliant, and he remained aboard as a crewmember upon the ship's return to duty. He tried to console Nancy Bryce when he learned that her father had perished aboard the USS Gallant. (TOS comic: "The Wormhole Connection")
- Welkin's rank and division specialty were not specifically referred to, but he wore a gold undershirt, meaning he could have been a pilot, engineer or filled some other administrative role.