"- Three!"
-117 wasn't conceived in the -Century era. The number was used as a deliberate 'cover' when its official title was still only 'Senior Trend'. It helped that Tonopah and Groom routinely had ATC traffic referred to as F-113s, -114s, etc. - the ex-Egyptian and Algerian MiG-21s and 23s and the Syrian MiG-17s. The -117 'fitted right in'.
"Out!"