Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 2
Situational Awareness; Distraction; Confusion
Airspace Violation All Types; Deviation - Altitude Excursion From Assigned Altitude; 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
Human Factors; Procedure
Aircraft X was on vectors for HIO ILS RY 13 approach. I issued the approach clearance after vectoring them through the final for in-trail spacing. I got a good readback for the clearance and altitude to maintain. Approximately 2 minutes later I noticed the track jump; but since we use FUSION radar with only two primary radar inputs I assumed it was related to the radar. When the track did not return after a few seconds; I verified they were on the approach. I realized they were off course and descending through the MVA so I issued a Low Altitude Alert and climbed them to 040. They descended to 030 in a 035 MVA before climbing back up. I canceled the approach clearance and issued vectors to re-join the approach. They flew through the localizer again; and after I corrected their heading to join I issued a new approach clearance.I believe flight training was in progress and the weather was IMC. I don't know what caused the aircraft to veer off course; I'm just glad I caught it.
P80 controller vectors aircraft onto final and notices the track jump. Controller thinks the jump is related to FUSION radar. Issues another heading and the aircraft finally gets on final after third attempt. Aircraft enters lower MVA due to not turning correctly.