Narrative:

Aircraft X descending on radar vector okc RWY35R from deckk from 15;000 feet to 7;000 feet. My co-worker was working this aircraft in my airspace with approval. I had just had a VFR come into conflict with my IFR arrival and the supervisor suggested that I allow my co-worker to work this second arrival into okc to alleviate workload. We stopped aircraft X at 7;000 feet to avoid an unidentified VFR aircraft maneuvering at the time around 5;000 - 6;500 feet. My co-worker vectored aircraft X to the west of the unknown aircraft and issued traffic. Aircraft X reported aircraft in sight and was told to maintain visual separation; descend and maintain 4;000 feet. Aircraft X reported traffic no factor and continued his descent. The unknown aircraft then reversed course and became in direct conflict with aircraft X. Aircraft X abruptly began to climb in accordance with a TCAS/RA. The unknown aircraft began a steep and fast descent at approximately the same time. Separation was regained and aircraft X landed at okc without further incident. A third co-worker watched the unknown target become identified by oun tower. We never had any contact with this unknown aircraft.inform the flight school of the danger of maneuvering in this area when multiple aircraft are inbound to okc final and okc satellite airports. This is a constant problem with airlines and other GA aircraft performing TCAS/RA maneuvers or being vectored away from VFR practice area aircraft causing delays to air traffic. Suggest to the flight school to either call for flight following; fly at a lower altitude or maneuver elsewhere. This is not illegal but highly dangerous. This happened three times today.

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Original NASA ASRS Text

Title: OKC Approach Controller reports about two different events involving flight school aircraft that gets in the way of arrival traffic to primary airport causing RA.

Narrative: Aircraft X descending on radar vector OKC RWY35R from DECKK from 15;000 feet to 7;000 feet. My co-worker was working this aircraft in my airspace with approval. I had just had a VFR come into conflict with my IFR arrival and the Supervisor suggested that I allow my co-worker to work this second arrival into OKC to alleviate workload. We stopped Aircraft X at 7;000 feet to avoid an unidentified VFR aircraft maneuvering at the time around 5;000 - 6;500 feet. My co-worker vectored Aircraft X to the west of the unknown aircraft and issued traffic. Aircraft X reported aircraft in sight and was told to maintain visual separation; descend and maintain 4;000 feet. Aircraft X reported traffic no factor and continued his descent. The unknown aircraft then reversed course and became in direct conflict with Aircraft X. Aircraft X abruptly began to climb in accordance with a TCAS/RA. The unknown aircraft began a steep and fast descent at approximately the same time. Separation was regained and Aircraft X landed at OKC without further incident. A third co-worker watched the unknown target become identified by OUN Tower. We never had any contact with this unknown aircraft.Inform the flight school of the danger of maneuvering in this area when multiple aircraft are inbound to OKC final and OKC Satellite airports. This is a constant problem with Airlines and other GA aircraft performing TCAS/RA maneuvers or being vectored away from VFR practice area aircraft causing delays to air traffic. Suggest to the flight school to either call for flight following; fly at a lower altitude or maneuver elsewhere. This is not illegal but highly dangerous. This happened three times today.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.