Date: 201808
Local time of day: 1201-1800
Location: ZZZ.TRACON, US
Flight conditions: IMC
Aircraft: Small Aircraft
Operating under: Part 91
Flight plan: IFR
Mission: Training
Flight phase: Climb
Airspace: Class C ZZZ
ATC / advisory: TRACON ZZZ
Reporter organization: Government
Reporter function: Approach
Reporter qualification: Air Traffic Control Developmental
Human factors: Training / Qualification; Workload; Communication Breakdown
Anomaly: ATC Issue All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Detector: Automation Air Traffic Control; Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance
Contributing factors: Airspace Structure; Weather; Procedure
Primary problem: Procedure

Narrative: I was working the DR position and there were multiple IFR practice approaches all day due to the weather being just below VFR minimums most of the day. As far as I can recall; Aircraft X came off IFR asking to be vectored for an instrument approach. I don't recall what approach he was on. I have not been given time to listen to the tapes so I am unsure what altitude aircraft was originally issued in climb out; what he reported climbing to in initial climb; or if I restated climb and maintain 090 and whether or not he read that back. As far as I know at this time; I issued vectors northbound to the downwind for an approach to either runway 17L or 17R with the belief that he was in a climb to 090. I think the aircraft was northbound on close to a 350 heading when the low altitude alert went off and got my attention. I noticed his altitude was below the MVA (Minimum Vectoring Altitude) but I was immediately alarmed as I figured he was just climbing slow. I asked him to verify still climbing to 090. He surprisingly responded in the negative and said he was given 080. I immediately reissued the climb to 090 and made a point of verifying if there were in obstacles that could be a danger. I did not see any and in my immediate judgement he was not in danger as long as he really was in the climb to 090. I immediately informed the supervisor that was sitting behind the desk that I had an IFR aircraft that ended up being below the MVA. I thought he was in a climb to 090; but when questioned he said he was given 080; and I did not notice there was a possible problem until the low altitude alert went off. The supervisor did not come over and look at the scope and tell me to issue any kind of safety alert and I already explained why I did not on my own. I was still focused working traffic at the time and asked the supervisor to listen to the tapes and advise me if any action needed to be taken (pilot deviation and brasher or maybe I messed up somewhere and didn't hear something I should have). After the supervisor said he listened to the tapes I distinctly remember him telling me; 'He was given 090 and read it back.' I was still working the same DR session at this point and I am pretty sure that Aircraft X was still flying. I was not asked to give a brasher warning to the pilot. After my session was over I did not feel the need to file an [ASRS Report] or listen to the tapes because I immediately told the Supervisor on the CIC (Controller-in-Charge) position; he said he listened to the tapes; and I was not told that any action needed to be taken. I was thankful the low altitude alert did its job and alerted me in a timely enough fashion to fix a problem before anything bad happened. I already explained that I have not listened to the tapes and I am unsure where the fault in miscommunication happened. I was busy working the radar position all day with an unusual amount of IFR and IFR practice approach aircraft that were necessitated because of the weather. I noticed that something odd happened; fixed it to the best of my ability at the time; and immediately informed the supervisor who did not tell me to take any kind of action. I am sure better recommendations on how to avoid this situation in the future can be found after examining the tapes and determining where the break in communication occurred. All IFR aircraft doing practice approaches are issued 090 as their standard climb out. It's possible he said something else and I missed it. My attention could have been split or not fully on him at the time and maybe I only heard what I expected to hear. In the future I will certainly make it a point to go back and listen to the tapes myself.




Synopsis: TRACON Controller reported a small aircraft at 8;000 feet entered a higher Minimum Vectoring Altitude.