US Air Force Lt. Col. John "Shorty" Powers popularized the expression "A-ok" while NASA's public affairs officer for Project Mercury, and was reported as attributing it to astronaut Alan Shepard during his Freedom 7 flight. However, the NASA publication This New Ocean: A History of Project Mercury says in a footnote: "A replay of the flight voice communications tape disclosed that Shepard himself did not use the term." and that "Tecwyn Roberts of STG and Capt. Henry E. Clements of the Air Force had used 'A.OK' frequently in reports written more than four months before the Shepard flight." Apparently, the first documented use of "A-ok" is contained within a memo from that Tecwyn Roberts, a Flight Dynamics Officer, to Flight Director (entitled "Report on Test 3805", dated Feb 2, 1961) in penciled notes on the countdown of MR-2 (Mercury-Redstone 2), dated Jan[uary] 31, 1961. In his book The Right Stuff author Tom Wolfe wrote that Powers had borrowed it from NASA engineers who used it during radio transmission tests because "the sharper sound of A cut through the static better than O".
The phrase can be accompanied by, or substituted with, the A-OK sign.
- "Calm Voice from Space". Time. Time Inc. March 2, 1962. Retrieved April 3, 2011. (subscription required (. ))
- Wolfe, Tom (1988). The Right Stuff (17th print ed.). Toronto: Bantam Books. p. 227. ISBN 9780553275568. Retrieved June 28, 2015 – via Google Books.
- Swenson, Loyd S. Jr.; Grimwood, James M.; Alexander, Charles C. (1989). "This New Ocean: A History of Project Mercury, Chap. 10: 'Ham Paves the Way'". Footnote 37. NASA (National Aeronautics and Space Administration). Retrieved June 22, 2015.
In reporting the Freedom 7 flight, the press attributed the term to Astronaut Shepard, ... A replay of the flight voice communications tape disclosed that Shepard himself did not use the term. . It was Col. John A. "Shorty" Powers ... Tecwyn Roberts of STG and Capt. Henry E. Clements of the Air Force had used "A.OK" frequently in reports written more than four months before the Shepard flight. ... Other sources claim that oldtime railroad telegraphers used "A-OK" as one of several terms to report the status of their equipment. Be that as it may, Powers, "the voice of Mercury Control," by his public use of "A.OK," made those three letters a universal symbol meaning "in perfect working order."
- Strauss, Mark (April 15, 2011). "Ten Enduring Myths About the U.S. Space Program: 5. "Alan Shepard is A-Okay"". Smithsonian. Smithsonian Institution. p. 3. Retrieved September 8, 2011.
- "Tecwyn Roberts: A-OK." llanddaniel.co.uk. Retrieved: May 5, 2011.[unreliable source?]