Narrative:

Aircraft X was inbound to eug from the east. Aircraft X checked in with the current ATIS and altitude. Aircraft X was issued vectors for the ILS runway 16R approach. Aircraft X was issued a turn to the localizer and clearance for the ILS at 2;800 the read back was correct. Aircraft X flew through the localizer; I issued a 140 heading to join final. Aircraft X started descending through 2;800 in a 2;800 MVA. I advised aircraft X it appeared they were descending through 2;800 and restated the 2;800 until established. Aircraft X replied; 'we're considered established'. I pointed out the airport and asked if aircraft X had the airport in sight. Aircraft X had the airport in sight and was cleared for the visual approach to runway 16R and switched to the tower. Brasher warning was not given.I should have turned aircraft X sooner to final so [that] the fly through didn't happen. In similar situation situations; I will reissue the altitude with the corrective heading to join final.

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Original NASA ASRS Text

Title: EUG TRACON Controller reported not issuing prompt corrective vectors; after an aircraft flew through the localizer and below the MVA.

Narrative: Aircraft X was inbound to EUG from the east. Aircraft X checked in with the current ATIS and altitude. Aircraft X was issued vectors for the ILS Runway 16R approach. Aircraft X was issued a turn to the localizer and clearance for the ILS at 2;800 the read back was correct. Aircraft X flew through the localizer; I issued a 140 heading to join final. Aircraft X started descending through 2;800 in a 2;800 MVA. I advised Aircraft X it appeared they were descending through 2;800 and restated the 2;800 until established. Aircraft X replied; 'We're considered established'. I pointed out the airport and asked if Aircraft X had the airport in sight. Aircraft X had the airport in sight and was cleared for the visual approach to Runway 16R and switched to the tower. Brasher warning was not given.I should have turned Aircraft X sooner to final so [that] the fly through didn't happen. In similar situation situations; I will reissue the altitude with the corrective heading to join final.

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.