Date: 202103
Local time of day: 1201-1800
Location: ZZZ.TRACON, US
Aircraft: PA-28 Cherokee/Archer/Dakota/Pillan/Warrior
Operator: Personal
Operating under: Part 91
Flight plan: IFR
Mission: Training
Flight phase: Initial Climb
Airspace: Class E ZZZ1
ATC / advisory: TRACON ZZZ
Aircraft component: Air/Ground Communication
Component problem: Malfunctioning
Reporter organization: Government
Reporter function: Approach
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown
Anomaly: Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; 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; Air Traffic Control Provided Assistance; Flight Crew Returned To Departure Airport; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Chart Or Publication; Human Factors; Aircraft
Primary problem: Aircraft

Narrative: I received the relief briefing from the previous controller and was briefed that an aircraft wanted to do multiple practice approaches at a satellite airport. The aircraft was on the climb out instructions when I instructed him to turn right heading 180 for vector for an ILS. The aircraft replied to that instruction and began to fly that heading. A minute or so later I noticed that the aircraft was veering to the right of the assigned heading. I instructed them to turn 10 degrees right. He didn't reply and I gave him the instructions again. He did not reply this time either. This is when I first became aware of this aircraft being NORDO (No Radio). I began to reach out multiple times to the aircraft and after a little time I heard him reply that he went back to the tower. I then questioned him as to why would he return to the tower frequency and gave him another instruction.The aircraft again did not respond. I also asked him to ident if he could hear me transmitting and that failed. Now I was becoming worried as I was aware this aircraft was level at 2;000 ft. and there is a Minimum Vectoring Altitude (MVA) south of him 5 to 6 miles that is 3;000 ft. I reached out to Tower to ask them if they could try to reach out to the aircraft. I also had another aircraft in the vicinity that I inquired if he could hear me and if that aircraft could transmit for me and try to contact the aircraft. Both of those attempts failed as well. I was now getting nervous as he was headed towards the two antennas with the MVA's at 3;000 ft. I then reached out to him on guard frequency and stated that if he heard me to climb immediately to 3;000 ft. I also alerted the Supervisor what was going on. Now I was seeing the aircraft entering the MVA area of 3;000 ft. and I transmitted in the blind a MVA alert and for them to climb immediately. There was still no contact with this aircraft. Now another aircraft was also trying to reach the NORDO aircraft as they heard the concern in my voice. After some time the pilot called me and said he was ready for the vector onto the ILS. Thats when the other aircraft transmitted the climb information and they began to climb. The aircraft then called me and stated he is having a serious problem with his radios and wanted to return to their departure airport. I then gave him vectors to return where the aircraft landed safely.I have no recommendations. This was an event that as a controller I did everything I could think of to get in contact with the aircraft but he was truly NORDO. In conclusion it was a equipment issue that caused the incident.




Synopsis: TRACON Controller reported an aircraft experiencing radio difficulties did not respond to ATC instructions and flew below the Minimum Vectoring Altitude.