(U.S. National Archives and Records Admin. Photo.) black-and-white photos 20mm Oerlikon Antiaircraft Guns December 16, 2016by Lone_Sentry_Admin1 min read Sailors man 20mm Oerlikon antiaircraft guns on the catwalk of the aircraft carrier USS Hornet (CV-12) in February 1945. (U.S. National Archives and Records Admin. Photo.) (U.S. National Archives and Records Admin. Photo.)