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CHI91FA108

1991-03-17 · THIEF RIVER FLS, Minnesota, United States · Fatal · 1 aircraft · Status: Completed

Airport TVF

Aircraft involved

Probable cause & findings

IMPROPER IFR PROCEDURE OF THE PILOT, WHILE INTERCEPTING THE ILS LOCALIZER, BY NOT MAINTIANING THE MINIMUM DESCENT ALTITUDE (MDA) FOR THAT SEGMENT OF THE APPROACH.

Factual narrative

DURING ARRIVAL, THE PLT WAS ADZD THAT THE 1745 CST WX WAS 500' BKN, 1000' OVC, VIS 3-1/2 MI WITH FOG. HE MADE AN ILS RWY 31 APCH, BUT AT 1928 CST, HE RPRTD A MISSED APCH. HE STATED THAT HE HAD SEEN 'THE LIGHTS' & REQUESTED ANOTHER APCH. THE ACFT WAS VECTORED FOR A 2ND ILS. WHEN IT WAS ABOUT 5 MI FROM THE OUTER MARKER (FAF), THE PLT WAS CLRD FOR THE APCH & TO CHANGE TO AN ADZY FREQ. HOWEVER, ABOUT 3 MI SE OF THE FAF, THE ACFT FLEW INTO LEVEL TERRAIN, WHILE STILL ON A WESTERLY HDG. MIN DSCNT ALT (MDA) FOR THIS SEGMENT OF THE APCH WAS 2700' MSL; THE ARPT ELEV WAS 1116'). NO PREIMPACT PART FAILURE OR MALFUNCTION OF THE AIRFRAME OR ENG WAS FOUND. THE 1945 CST WX AT THE ARPT HAD DETERIORATED TO 200' OVC & 1/4 MI VIS WITH FOG. Source: NTSB Aviation Accident Database (Pre-2008 Archive) Retrieved: 2026-02-12

Verbatim from NTSB's published report. Source file NTSB_1991_CHI91FA108.txt. Findings + structured fields enriched from FAA avall.mdb. Full investigation docket on data.ntsb.gov ↗.

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