When We Left Earth - The NASA Missions Quotes

Gene Kranz: Most of us came in from aircraft flight test. We knew nothing about rocketry, we knew nothing about spacecraft, we knew nothing about orbits.
Narrator: Gene Kranz joins the Flight Director's team in NASA's earliest days.
Gene Kranz: So it was a question of learning to drink from a fire hose. We had to learn all about trajectories; I'd never heard the term "retrofire," coming on down from orbit, getting the spacecraft back home.

Movie: When We Left Earth - The NASA Missions