Falcon 20FJF/20C/20D/20E/20F
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 9
Situational Awareness; Training / Qualification
Deviation - Altitude Excursion From Assigned Altitude; Deviation - Altitude Overshoot; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Provided Assistance
Human Factors
I was conducting training on Sector 1; providing services into and out of [the area]. The two sectors in the area were combined; and control of the arrivals and departures into ZZZ airport were also our responsibility. Traffic was light. Aircraft X checked in and the trainee advised them to expect a visual approach to Runway 30 at ZZZ; and issued them direct the airport. Later; I intended on discussing with the trainee that a turbojet aircraft is likely not wanting to go direct airport to set up for landing. The aircraft reported the airport in sight after being issued the location by the trainee; and subsequently issued the visual approach. About 12 miles south of the airport; the trainee switched Aircraft X to ZZZ tower. I observed the aircraft make a turn to the east; which appeared to bring them towards a 5-6 mile final for Runway 30. At this point I queried the trainee as what they thought Aircraft X was doing. They weren't sure. Then the aircraft appeared to turn more; which made it look like it no longer was lining up for Runway 30 at ZZZ. The altitude also continued to drop. At this point I initiated a call to ZZZ tower; as the LA [Low Altitude Alert] began to go off. I asked ZZZ to find out what Aircraft X was doing. ZZZ said they weren't sure; and got off the line to radio the pilot. As it turned out; Aircraft X was lined up from Runway 26 at ZZZ1. It appeared they were on a roughly 1 mile final and well below 500 feet AGL; when they finally pulled up. The pilot was uncertain where they were; and ZZZ had to put them back on approach frequency to get vectored to the instrument approach. It seems that controllers don't regularly call towers when LA's go off. Especially in visual conditions. In this case; weather was not a factor. But a wrong surface landing was narrowly prevented.
TRACON Controller reported observing an aircraft do unusual turns and descend; checked with appropriate tower and found out aircraft was descending and lining up for a wrong airport.