Tibbets ordered a disguise for the Enola Gay and escort aircraft on the Hiroshima mission. He had a big black letter R (the insignia of another unit on Tinian, the 313th Bomb Wing) painted on the tail, replacing the 509th’s distinctive arrow in a circle. Also for security, Tibbets changed the call sign from “Victor” to “Dimples.” The Enola Gay flew the mission as “Dimples Eight Two.”