Small Aircraft; Low Wing; 1 Eng; Retractable Gear
Air Traffic Control Fully Certified
Situational Awareness; Human-Machine Interface; Troubleshooting
Aircraft Equipment Problem Critical; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Provided Assistance; Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented; Flight Crew Overcame Equipment Problem; Flight Crew Requested ATC Assistance / Clarification; General Flight Cancelled / Delayed
Aircraft
Aircraft X was handed off at 8;000 feet. I vectored the aircraft on a 280 heading to the final approach course. After several vector adjustments I asked the pilot their current heading and wanted to verify their heading indicator was correct because there was a 30-40 degree track difference. After vectoring the aircraft and clearing them for the ILS approach I noticed the aircraft left of the localizer and advised them. The pilot advised they were correcting back to the localizer. After seeing the aircraft back on the localizer I transferred the aircraft to Tower. Aircraft X then came back to approach and said they were having difficulties. I issued a 360 heading and climb to 3000 feet and cancelled the approach clearance. The aircraft did not read back the altitude twice. I observed the aircraft deviating from the 360 heading and asked if they needed assistance. Aircraft X said their gyro instruments had failed. I issued a low altitude alert and tried to climb the aircraft again. Aircraft X then said they had ground contact and they wanted to descent. The Minimum Vectoring Altitude (MVA) in the area was 2600 feet. The pilot reported ground contact and requested guidance the airport. The Controller in Charge (CIC) coordinated a landing clearance with Tower and the aircraft landed.Given the circumstance I tried to accommodate the pilot with their intentions even though they were below the MVA. The aircraft was below the MVA but had 'ground contact' and I had just observed them maneuvering very erratically in IMC conditions.
A TRACON Controller reported they had to vector an aircraft to its destination below the Minimum Vectoring Altitude because of instrument failure.