FTW01FA033 · Cessna 421B
Cessna 421B · Accident: in flight collision with terrain/water on approach
From Altus Quartz Mountain Regional Airport (AXS) to University of Oklahoma Westheimer Airport (OUN)
Event
- NTSB case
- FTW01FA033
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 2 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Instrument Meteorological Cond
Cessna 421B
- Aircraft type
- Cessna 421
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N52KL
- Operator
- Earl W. Nash · private individual
- Onboard fatalities
- Unknown
- Route
- From Altus Quartz Mountain Regional Airport (AXS), Altus, OKTo University of Oklahoma Westheimer Airport (OUN)
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Approach
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- In flight collision with terrain/water
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Pilot in command › IFR procedure, not followed
- Pilot in command › Minimum descent altitude, continued below
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
According to air traffic control communication and radar data, the flight was VFR over the top, approximately 7,900 feet, and requested an IFR clearance to the destination airport. The flight was issued an IFR clearance and, subsequently, was cleared for the localizer runway 3 approach. Radar data indicates that the airplane intercepted the localizer and began tracking inbound. Once the airplane reached the final approach fix, the airplane entered a shallow descent, but did not reach the MDA until after passing the missed approach point (MAP). The airplane flew past the MAP, continued to descend and over flew the runway. The final radar return was captured at 1,200 feet and one mile northeast of the airport, where the airplane was later located. The weather observation facility located at the airport reported that, 11 minutes before the accident, the winds were from 140 degrees at 6 knots, ceiling 200 feet overcast, visibility 1/4 miles in fog, temperature 45 degrees Fahrenheit and dew point 45 degrees Fahrenheit. A person who was at the airport at the time of the accident reported that the "clouds were low and visibility was poor." Toxicological testing performed on the pilot by the FAA's Civil Aeromedical Institute, Oklahoma City, Oklahoma, revealed the following: 0.121 (ug/ml, ug/g) amphetamine detected in blood, 0.419 (ug/ml, ug/g) amphetamine detected in liver, amphetamine detected in kidney, 4.595 (ug/ml, ug/g) methamphetamine detected in blood, 5.34 (ug/ml, ug/g) methamphetamine detected in liver, 3.715 (ug/ml, ug/g) methamphetamine detected in kidney, pseudoephedrine present in blood, and pseudoephedrine present in liver. The airframe and engines were examined and no anomalies were discovered that would have effected operation of the flight.
Probable cause
the pilot's failure to follow the instrument approach procedure and his continued descent below the prescribed minimum descent altitude (MDA). Contributory factors were the pilot's physical impairment from drugs, the low ceiling, fog, and dark night light conditions.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record FTW01FA033
- Event ID
- 20001218X45437
- Case number
- FTW01FA033
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 2d1ebe6f7aadc81235dd755f3044a15136b39cb9383fad4fe3d797135976b7d0; retrieved 2026-09-20T20:43:56.344Z.