Ryan was a human who lived in the 23rd century. She served Starfleet as a lieutenant.

In 2273, Lieutenant Ryan had recently been assigned to the USS Enterprise (NCC-1701). She filled in for Lieutenant Commander Hikaru Sulu as helm officer when he was sent into Japan's past by the omnipotent being Weyland. Ryan warned Captain James T. Kirk that the Enterprise's orbit around Cragon V was beginning to decay, and detected the Klingons Kral and Vladra on sensors when they had been ejected from an airlock of the IKS Ghargh. (TOS novel: Home is the Hunter)

USS Enterprise (NCC-1701) flight control personnel
Under Robert April	Ferarra • Florida • Nobis • Po • Soulian	Under Christopher Pike	Mohindas • Number One • Tyler • Vincent • Wayne
Under James T. Kirk (first five-year mission)	Akrumba • Alden • Arex • Bailey • Barrows • Chekov • Cheung • DePaul • DeSalle • Farrell • Green • Hadley • Hansen • Harrison • Hwavirë • Kelso • Kerby • Kyle • Latimer • Leslie • Mitchell • Rahda • Riley • Sanchez • Shaffer • Stiles • Spinelli • Sulu • Vitali • Walking Bear
Subsequent missions under Kirk & Spock	Bryce • Chekov • DiFalco • Domenick • Ledoux • Haarv • Lee • Saavik • Ilia • Sherwood • Ryan • Sulu • T'Lara
see also: administrative personnel • communications personnel • engineering personnel • medical personnel • security & tactical personnel • sciences personnel • senior staff • unnamed