Ensign Frost was a 23rd century Human, an engineer and experienced pilot serving Starfleet on board the Federation starship USS Enterprise in the 2260s.
Montgomery Scott considered him a good engineer, but young and unfamiliar with shuttle engines. Scott had worked with him for several years.
History
In 2269, when the transporter would not engage to beam down a landing party to the surface of the planet Anomaly, Kirk asked Frost to take the group down in a shuttlecraft. Frost's passengers consisted of Kirk, Sharon Follett, Octavio Hernandez and security officers Hevelin, Bounds, and Mark Moore. Frost compensated for buffeting winds from a hot jungle and landed smoothly at the beam-down site.
To clear tall savannah grass around the shuttle after phasers and other equipment malfunctioned, Frost suggested rejigging heating elements in emergency food-pak rations to ignite a brush fire. Later, when a rescue shuttle landed nearby, Frost double-checked it to confirm that it had similar mechanical problems. (TOS novel: Planet of Judgment)
