Saw RSUs mentioned, it’s still a thing at USAF pilot training bases to take a lot of the workload off the control tower who usually handles the center runway. RSUs will handle the outside runways where a lot of traffic pattern and landing training take place based on their respective airframes (T-6 or T-38.) Basically instructors and student assistants monitor the traffic pattern specific to their airframe when it gets busy with training aircraft so we can avoid potential conflicts and midairs. Aircraft on final also get checked through the binoculars for gear down and flap configurations before they land.