Narrative:

I was working the radar position combined and vectoring aircraft X for an ILS approach. I issued aircraft X a descent to 3000 feet and a turn to heading 290 degrees which pointed him toward a 3600 foot minimum vectoring altitude (MVA). A preceding arrival; aircraft Y; was already on approach and talking to tower about 6 miles ahead of aircraft X when tower called down to advise me that aircraft Y was responding to a TCAS RA. There were no primary radar returns in the area and they did not see an aircraft. There is doubt of whether or not there was actually an aircraft there in the first place.after aircraft Y reported to tower that he was responding the too resolution advisory (RA) and maintaining 3000 feet and runway heading; local control called down to coordinate. At that exact time is when I should have been clearing aircraft X for the approach; keeping him clear of the 3600 foot MVA. However I was distracted by the coordination. As soon as it was completed; I turned aircraft X to a 180 heading. Due to the slow rate of turn; aircraft X entered the 3600 foot MVA for about a half mile before returning to the 2700 foot MVA along final. A safety alert was not issued as it was difficult to tell if the aircraft had actually entered the 3600 foot MVA or not. Both flights continued without further incident. It was never determined if there was an aircraft along final that caused the TCAS RA. If I had descended aircraft X to 3600 feet instead of to 3000 feet there would not have been an MVA bust. The unexpected coordination and TCAS RA made a time sensitive transmission difficult. Local control did the right thing by informing me of the TCAS and what the aircraft was doing. I made the mistake of not protecting the airspace and not issuing a safety alert.

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Original NASA ASRS Text

Title: CHA Controller reported being distracted and forgot to turn an aircraft onto the final approach course; causing it to descend below the Minimum Vectoring Altitude.

Narrative: I was working the radar position combined and vectoring Aircraft X for an ILS approach. I issued Aircraft X a descent to 3000 feet and a turn to heading 290 degrees which pointed him toward a 3600 foot Minimum Vectoring Altitude (MVA). A preceding arrival; Aircraft Y; was already on approach and talking to tower about 6 miles ahead of Aircraft X when tower called down to advise me that Aircraft Y was responding to a TCAS RA. There were no primary radar returns in the area and they did not see an aircraft. There is doubt of whether or not there was actually an aircraft there in the first place.After Aircraft Y reported to tower that he was responding the too Resolution Advisory (RA) and maintaining 3000 feet and runway heading; Local Control called down to coordinate. At that exact time is when I should have been clearing Aircraft X for the approach; keeping him clear of the 3600 foot MVA. However I was distracted by the coordination. As soon as it was completed; I turned Aircraft X to a 180 heading. Due to the slow rate of turn; Aircraft X entered the 3600 foot MVA for about a half mile before returning to the 2700 foot MVA along final. A safety alert was not issued as it was difficult to tell if the aircraft had actually entered the 3600 foot MVA or not. Both flights continued without further incident. It was never determined if there was an aircraft along final that caused the TCAS RA. If I had descended Aircraft X to 3600 feet instead of to 3000 feet there would not have been an MVA bust. The unexpected coordination and TCAS RA made a time sensitive transmission difficult. Local Control did the right thing by informing me of the TCAS and what the aircraft was doing. I made the mistake of not protecting the airspace and not issuing a safety alert.

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.