“‘Roger That!’: The Life of Roger B. Chaffee, Michigan’s First Astronaut”, presented by Glen E. Swanson.
From the earliest days of wireless communication, the Morse code letter R (dit-dah-dit) has been used to indicate ‘O.K.—understood.’ So when advances in telecommunications eventually allowed voices to be heard, ‘Roger’ was the logical voice-phone equivalent. Variations of the word, including “Roger That” eventually came into use by pilots to mean ‘your message received and understood.’ Later it came into general use to mean ‘all right, OK.’
On the afternoon of January 27, 1967, the three prime crewmembers of the first crewed Apollo mission left the NASA transfer van that took them out to the launch pad at Cape Canaveral, Florida. There, the fully suited men rode the elevator to the 218-foot level of the launch tower, where they crossed the access arm to climb into their spacecraft.