I took another look and seen a fighter jet silhouette so ya could be training mission. Now Dept of Homeland Security helo has been flying overhead but it is Mode-S. Government at work. Seen some Talons, E3B Sentry's, KC-135R's, KC 10A's, i forgot what the propeller driven plane was.
Heavy transports fly over the US all the time,especially when they have units training at Nellis Afb during exercise training like Red Flag,in one day i had RAF(Royal Air Force),RAAF(Royal Australian Air Force) and from time to time you will see heavy tankers from many countries as well.,Oklahoma is right smack in the middle of the country,so they fly over all the time.
YA I noticed TIK is quite busy daily never ADS-B mode only Mode-S except for a few occasions like one tanker did a fly over at KOKC after making 3 circles around the city. My Nooelec NESDR Smart dongle is doing a good job.
COMSTRATCOMMWING ONE (SCW-1) (Navy)
552d Air Control Wing (USAF)
513th Air Control Group (USAF)
507th Air Refueling Wing (USAFR)
And bunches more ... especially the Oklahoma City Air Logistics Complex which "performs programmed depot maintenance on the C/KC-135, B-1B, B-52 and E-3 aircraft; expanded phase maintenance on the Navy E-6 aircraft; and maintenance, repair and overhaul of F100, F101, F108, F110, F117, F118, F119 and TF33 engines for the Air Force, Air Force Reserve, Air National Guard, Navy and foreign military sales."
F100s? Didn't those get phased out decades ago? Oh, F100 *engine* ...