A U.S. Air Force Air Defence Command Lockheed RC-121D <i>Warning Star</i> in flight with the three major subsonic interceptors in the mid-1950s (l-r): Lockheed F-94C <i>Starfire</i>, North American F-86D <i>Sabre</i>, and Northrop F-89D <i>Scorpion</i>.
U.S. Navy
<a rel="nofollow" class="external text" href="http://www.navy.mil/ah_online/department_arch.html">U.S. Navy All Hands magazine</a> <a rel="nofollow" class="external text" href="http://www.navy.mil/ah_online/archpdf/ah195602.pdf">February 1956</a>, p. 22.