ZFW controller reported a near midair collision between an aircraft under ZFW control and a VFR airc...

Narrative:

I was training an r-side and aircraft X going to rockwall (F47) was at 040 and requested lower. Trainee issued 025 and we called to apreq (approval request) with D10. They told us the lowest they could go is 030. I climbed aircraft X up to 030 and he then reported and aircraft directly underneath him. I scoped in and only saw two aircraft; but neither with traffic for him yet he still said there was an aircraft right under him. I called approach and asked them if they saw anything and they said they just now were able to see someone. As they said that I finally was able to see the primary target begin to diverge from underneath the target of aircraft X. After switching the aircraft to D10; I had the controller in charge (controller-in-charge) call the airport manager to get the pilot to call us. After speaking with the pilot; he said had I [not] climbed him to 030; he thinks he would have hit the other aircraft and that he may have come to within 125 feet of him.

Original NASA ASRS Text

Title: ZFW Controller reported a NMAC between an aircraft under ZFW Control and a VFR aircraft not under ATC Control.

Narrative: I was training an R-side and Aircraft X going to Rockwall (F47) was at 040 and requested lower. Trainee issued 025 and we called to apreq (approval request) with D10. They told us the lowest they could go is 030. I climbed Aircraft X up to 030 and he then reported and aircraft directly underneath him. I scoped in and only saw two aircraft; but neither with traffic for him yet he still said there was an aircraft right under him. I called Approach and asked them if they saw anything and they said they just now were able to see someone. As they said that I finally was able to see the primary target begin to diverge from underneath the target of Aircraft X. After switching the aircraft to D10; I had the CIC (Controller-in-Charge) call the Airport Manager to get the pilot to call us. After speaking with the pilot; he said had I [not] climbed him to 030; he thinks he would have hit the other aircraft and that he may have come to within 125 feet of him.

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.

Attributes
ACN	1573782
Time
Date	201808
Local Time Of Day	0601-1200
Place
Locale Reference	ZFW.ARTCC
State Reference	TX
Aircraft 1
Make Model Name	SR22
Operating Under FAR Part	Part 91
Flight Phase	Descent
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Plan	VFR
Person 1
Function	Enroute Instructor
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 7
Events
Anomaly	ATC Issue All Types Conflict NMAC

ZFW controller reported a near midair collision between an aircraft under ZFW control and a VFR aircraft not under ATC control.