# NTSB investigations: Unknown

NTSB aviation accident and incident investigations since 1962: the probable cause, findings, aircraft, crew, weather and docket of each, linked to the FAA registry and the FAA’s own reports.

Page 22 of 40 · 1,978 cases

## Cases, newest first

- [NTSB FTW93TA#03](https://openairdocs.org/ntsb/FTW93TA%2303.md): Bell 206B · Dallas, TX · Accident · No injuries · Final report · Mar 16, 1993 · N3211N · Substantial damage
- [NTSB CHI93FAMS2](https://openairdocs.org/ntsb/CHI93FAMS2.md): Piper PA-28R-200 · Grand Haven, MI · Accident · 1 fatal · Missing aircraft · Final report · Mar 15, 1993 · N15206 · Destroyed
  > undetermined.
- [NTSB LAX93LA124](https://openairdocs.org/ntsb/LAX93LA124.md): Bertone Challenger II · Boulder City, NV · Accident · 1 fatal · Limited investigation · Final report · Feb 18, 1993 · N4391V · Destroyed
  > The pilot's loss of airplane control due to physical impairment as a result of either drugs or other cardiovascular reasons, or both.
- [NTSB CHI93FAMS1](https://openairdocs.org/ntsb/CHI93FAMS1.md): Cessna 182P · Portage, IN · Accident · 1 fatal · Missing aircraft · Final report · Feb 6, 1993 · N7227N · Destroyed
  > Undetermined.
- [NTSB LAX93FAMS2](https://openairdocs.org/ntsb/LAX93FAMS2.md): Piper PA-28-181 · Missing Acft, CA · Accident · 4 fatal · Missing aircraft · Final report · Dec 6, 1992 · N81453 · Destroyed
  > Undetermined.
- [NTSB DEN93LA014](https://openairdocs.org/ntsb/DEN93LA014.md): Champion 7KCAB · Boulder, CO · Accident · No injuries · Limited investigation · Final report · Dec 2, 1992 · N2751G · Substantial damage
  > Undetermined.
- [NTSB LAX93FAMS1](https://openairdocs.org/ntsb/LAX93FAMS1.md): Grumman AA-1B · Pacific Ocean (Pacific Ocean) · Accident · 2 fatal · Missing aircraft · Final report · Nov 6, 1992 · N9890L · Destroyed
  > Undetermined. The aircraft was not located.
- [NTSB SEA93LA019](https://openairdocs.org/ntsb/SEA93LA019.md): Beech A35 · Vancouver, WA · Accident · No injuries · Limited investigation · Final report · Oct 27, 1992 · N8501A · Substantial damage
  > Design stress limits of the aircraft were exceeded.
- [NTSB DEN93IA005](https://openairdocs.org/ntsb/DEN93IA005.md): Mcdonnell Douglas DC-9-82 · Denver, CO · Incident · No injuries · Incident investigation · Final report · Oct 13, 1992 · N72822 · Minor damage
  > An inadvertent attempt, by unknown persons, to start the APU which had been placarded as inoperative. Factors were: inadequate procedures in rendering the APU incapable of being started when inoperative.
- [NTSB ANC93FA148](https://openairdocs.org/ntsb/ANC93FA148.md): Champion 7EC · Chugiak, AK · Accident · 1 fatal · Field investigation · Final report · Oct 9, 1992 · N8958R · Destroyed
  > Collision with the terrain for an unknown reason.
- [NTSB MIA92LA181](https://openairdocs.org/ntsb/MIA92LA181.md): Aero Commander 100 · Panacea, FL · Accident · Minor injuries · Limited investigation · Final report · Sep 15, 1992 · N3791X · Substantial damage
  > Failure of the nose landing gear push/pull rod end bearing for undetermined reasons.
- [NTSB CHI92FAMS3](https://openairdocs.org/ntsb/CHI92FAMS3.md): Cessna 150H · Manistee, MI · Accident · 1 fatal · Missing aircraft · Final report · Sep 12, 1992 · N6759S · Destroyed
  > Undetermined
- [NTSB MIA92LA177](https://openairdocs.org/ntsb/MIA92LA177.md): Cessna A150K · Palatka, FL · Accident · No injuries · Limited investigation · Final report · Sep 7, 1992 · N8367M · Substantial damage
  > The pilot in command's failure to maintain airspeed while performing a go around resulting in the aircraft stalling and descending uncontrolled to the ground.
- [NTSB FTW92FA224](https://openairdocs.org/ntsb/FTW92FA224.md): Robinson R22 · Alpine, TX · Accident · 1 fatal · Field investigation · Final report · Sep 5, 1992 · N4073S · Destroyed
  > Failure by the pilot-in-command, for unknown reasons, to maintain sufficient altitude to clear surrounding terrain. Factors were mountainous terrain and high density altitude.
- [NTSB CHI92FA266](https://openairdocs.org/ntsb/CHI92FA266.md): Piper PA-28-180 · Ness City, KS · Accident · 4 fatal · Field investigation · Final report · Sep 5, 1992 · N5272L · Destroyed
  > The pilot-in-command's (CFI) failure to maintain control of the airplane.
- [NTSB ANC92FAMS3](https://openairdocs.org/ntsb/ANC92FAMS3.md): Beech 35 · Missing, AK · Accident · 2 fatal · Missing aircraft · Final report · Aug 17, 1992 · N216JB · Destroyed
  > Missing aircraft due to undetermined causes and factors
- [NTSB CHI92FAMS2](https://openairdocs.org/ntsb/CHI92FAMS2.md): Cessna 172N · Lake Michigan, MI · Accident · 4 fatal · Missing aircraft · Final report · Jul 18, 1992 · N4500E · Destroyed
  > Undetermined.
- [NTSB MIA92LA151](https://openairdocs.org/ntsb/MIA92LA151.md): Consolidated Aeronautics LA-4-200 · FL · Accident · No injuries · Limited investigation · Final report · Jul 9, 1992 · N2969P · Substantial damage
  > Substantial damage to the airplane during Unknown phase of flight for undetermined reasons.
- [NTSB NYC92FIG01](https://openairdocs.org/ntsb/NYC92FIG01.md): Tierra II · Williamsport, MD · Accident · 1 fatal · Final report · Jun 28, 1992 · N531PJ · Destroyed
  > The pilot's alcoholic impairment of efficiency and judgement resulting in a loss of control of the airplane during a forced landing following a power loss for an undetermined reason.
- [NTSB SEA92FA114](https://openairdocs.org/ntsb/SEA92FA114.md): Cessna 172B · Eatonville, WA · Accident · 1 fatal · Field investigation · Final report · May 22, 1992 · N7579X · Destroyed
  > Undetermined.
- [NTSB ANC92FAMS2](https://openairdocs.org/ntsb/ANC92FAMS2.md): Cessna 340 · Yakutat, AK · Accident · 5 fatal · Missing aircraft · Final report · May 4, 1992 · N69469 · Destroyed
  > Missing aircraft due to undetermined causes.
- [NTSB MIA92FAMS1](https://openairdocs.org/ntsb/MIA92FAMS1.md): Piper PA-28-181 · Missing · Accident · 1 fatal · Missing aircraft · Final report · Apr 20, 1992 · N4319N · Destroyed
  > Undetermined.
- [NTSB DEN92LA043](https://openairdocs.org/ntsb/DEN92LA043.md): Cessna 172Q · Englewood, CO · Accident · No injuries · Limited investigation · Final report · Mar 18, 1992 · N66076 · Substantial damage
  > Undetermined.
- [NTSB BFO92TA#01](https://openairdocs.org/ntsb/BFO92TA%2301.md): Mcdonnell Douglas 369E · Clinton, MD · Accident · No injuries · Final report · Feb 12, 1992 · N1600Q · Substantial damage
- [NTSB LAX92FA102](https://openairdocs.org/ntsb/LAX92FA102.md): Piper PA28-161 · Mountain Pass, CA · Accident · 4 fatal · Field investigation · Final report · Jan 25, 1992 · N8432K · Destroyed
  > The pilots failure to maintain the aircraft's airspeed above the stall speed (vs) that resulted in an inadvertent entry into a stall/spin.
- [NTSB MIA92LA068](https://openairdocs.org/ntsb/MIA92LA068.md): Piper PA-32-301 · Atlantic Ocean (Atlantic Ocean) · Accident · 3 fatal · Limited investigation · Final report · Jan 23, 1992 · N8300X · Destroyed
  > Undetermined. The airplane crashed in the Atlantic Ocean and was not located.
- [NTSB FTW92FA048](https://openairdocs.org/ntsb/FTW92FA048.md): Cessna 182 · Santa Teresa, NM · Accident · 1 fatal · Field investigation · Final report · Dec 16, 1991 · N5530B · Destroyed
  > The pilot's failure to maintain control. Factors were the dark night, pilot's apprehension, pilot's lack of instrument experience, spatial disorientation, poor instrument location, visual perception and inadequate cockpit lighting.
- [NTSB LAX92FA064](https://openairdocs.org/ntsb/LAX92FA064.md): Glasair SH-2R · Nuevo, CA · Accident · 1 fatal · Field investigation · Final report · Dec 6, 1991 · N614LS · Destroyed
  > The failure of the pilot to perform preventative maintenance on the airplane's powerplant which resulted in a loss of performance during an unknown phase of operation. Contributing to the accident was fouled spark plugs and the partial loss of aircraft…
- [NTSB FTW92FAMS1](https://openairdocs.org/ntsb/FTW92FAMS1.md): Grumman F9F-8T · Missing · Accident · 2 fatal · Missing aircraft · Final report · Oct 31, 1991 · N24WJ · Destroyed
  > Undetermined.
- [NTSB BFO92FA010](https://openairdocs.org/ntsb/BFO92FA010.md): Piper PA-28-140 · Chesapeake Bay, MD · Accident · 1 fatal · Field investigation · Final report · Oct 5, 1991 · N55657 · Destroyed
  > Undetermined. The aircraft wreckage has not been located.
- [NTSB MIA92GA002](https://openairdocs.org/ntsb/MIA92GA002.md): Cessna 172K · Everglades City, FL · Accident · 2 fatal · Final report · Oct 3, 1991 · N758JN · Destroyed
  > The pilot-in-command's improper management of fuel. This resulted in the airplane experiencing fuel exhaustion, forced landing, and in flight collision with terrain.
- [NTSB NYC91LA254](https://openairdocs.org/ntsb/NYC91LA254.md): Robinson R-22 · Point Judith, RI · Accident · 1 fatal · Limited investigation · Final report · Sep 24, 1991 · N950CW · Destroyed
  > The pilot become disoriented and lost control of the helicopter. Contributing to the accident was a dark night, flight over water, and the pilot's lack of total flight experience.
- [NTSB FTW91LA165](https://openairdocs.org/ntsb/FTW91LA165.md): Piper PA-28-150 · Van Horn, TX · Accident · 1 fatal · Limited investigation · Final report · Sep 21, 1991 · N5330W · Destroyed
  > The pilot's failure to maintain control of the airplane. A factor was the pilot's lack of total experience.
- [NTSB LAX91LA365](https://openairdocs.org/ntsb/LAX91LA365.md): Piper PA-38-112 · Oceano, CA · Accident · 2 fatal · Limited investigation · Final report · Aug 18, 1991 · N2526C · Destroyed
  > Unknown. The main airplane wreckage and the body of the pilot are presumed lost at sea.
- [NTSB CHI91DTG01](https://openairdocs.org/ntsb/CHI91DTG01.md): Cessna 172P · Bismarck, ND · Accident · 1 fatal · Final report · Jun 1, 1991 · N5478K · Destroyed
  > Spatial disorientation. Factors related to the accident are failure to obtain a preflight weather brief, vrf flight into IMC conditions and lack of total experience.
- [NTSB MIA91LA149](https://openairdocs.org/ntsb/MIA91LA149.md): Cessna 172M · Missing (Atlantic Ocean) · Accident · 1 fatal · Limited investigation · Final report · May 23, 1991 · N73186 · Destroyed
  > The lose of engine power for undetermined reasons which resulted in a forced landing and ditching in the atlantic ocean.
- [NTSB FTW91LA077](https://openairdocs.org/ntsb/FTW91LA077.md): Vuncannon Rotoway Exec 152 · Jonesboro, AR · Accident · Serious injuries · Limited investigation · Final report · May 10, 1991 · N316FV · Destroyed
  > The pilot's inadequate lookout and failure to maintain sufficient clearance from the wires for safe operation.
- [NTSB MIA91FAMS1](https://openairdocs.org/ntsb/MIA91FAMS1.md): Piper PA-24-260 · Missing, FL · Accident · 1 fatal · Missing aircraft · Final report · Apr 24, 1991 · N8938P · Destroyed
  > Undetermined.
- [NTSB ANC91LA043](https://openairdocs.org/ntsb/ANC91LA043.md): Piper PA-31T · Kenai, AK · Accident · No injuries · Limited investigation · Final report · Mar 31, 1991 · N308SC · Substantial damage
  > The failed nose gear shimmy dampner, contributing to the accident was the rough ice and snow covered ramps where the airplane had been operating and the lack of maintenance on the runways.
- [NTSB CHI91FA116](https://openairdocs.org/ntsb/CHI91FA116.md): Mooney M-20C · Prior Lake, MN · Accident · 1 fatal · Field investigation · Final report · Mar 26, 1991 · N9692M · Destroyed
  > Failure to maintain airspeed while executing a forced landing. Factors related to the accident were the pilot's improper inflight planning/decision, and fuel exhaustion.
- [NTSB DEN91LA030](https://openairdocs.org/ntsb/DEN91LA030.md): Cessna 206A · Carlsbad, NM · Accident · No injuries · Limited investigation · Final report · Jan 1, 1991 · N2691X · Substantial damage
  > A loss of control by the pilot during landing roll due to his failure to maintain directional control.
- [NTSB LAX91LA053](https://openairdocs.org/ntsb/LAX91LA053.md): Cessna T210N · Douglas, AZ · Accident · 2 fatal · Limited investigation · Final report · Dec 22, 1990 · XBBCR · Destroyed
  > An inflight loss of control of the airplane due to the pilot's physical impairment from the consumption of alcohol. A factor which contributed to the accident was an inoperative vacuum system.
- [NTSB MIA91GA034](https://openairdocs.org/ntsb/MIA91GA034.md): Asta N22S · Homestead Afb, FL · Accident · No injuries · Final report · Nov 28, 1990 · N5056D · Substantial damage
  > The bending overstress failure of the left main landing screwjack at an undetermined time during flight for undetermined reasons.
- [NTSB ANC91GAMS1](https://openairdocs.org/ntsb/ANC91GAMS1.md): Gulfstream Aerospace 690C · Deadhorse, AK · Accident · 3 fatal · Final report · Oct 12, 1990 · N45Q · Destroyed
  > Missing aircraft.
- [NTSB LAX91LA003](https://openairdocs.org/ntsb/LAX91LA003.md): Cessna 210 · Riverside, CA · Accident · 1 fatal · Limited investigation · Final report · Oct 6, 1990 · N9466T · Destroyed
  > Impairment of the pilot from use of drugs (cocaine), and his failure to maintain clearance (or altitude) from the mountain. Factors related to the accident were: darkness and the pilot's psychological condtion (depression).
- [NTSB LAX90DUG10](https://openairdocs.org/ntsb/LAX90DUG10.md): ELY Thorp T-18 · Claremont, CA · Accident · 2 fatal · Final report · Sep 25, 1990 · N9JE · Substantial damage
  > A loss of control for undetermined reason(s).
- [NTSB CHI90DEM09](https://openairdocs.org/ntsb/CHI90DEM09.md): Comben Bowers Flybaby IA · Cheboygan, MI · Accident · 1 fatal · Final report · Sep 13, 1990 · N1175B · Destroyed
  > Undetermined.
- [NTSB CHI90FAMS3](https://openairdocs.org/ntsb/CHI90FAMS3.md): Cessna 172M · Kewaunee, WI · Accident · 2 fatal · Missing aircraft · Final report · Aug 14, 1990 · N9529H · Destroyed
  > Undetermined.
- [NTSB ANC90LA143](https://openairdocs.org/ntsb/ANC90LA143.md): Piper PA-18-150 · Aniak, AK · Accident · 2 fatal · Limited investigation · Final report · Aug 12, 1990 · N3946Z · Substantial damage
  > Pilot lost control of the airplane as a result of encountering severe weather either during takeoff or landing. Contributing to the accident was the severe weather, rough water surface, and self-induced pressure to fly by the pilot.
- [NTSB MIA90LA170](https://openairdocs.org/ntsb/MIA90LA170.md): Piper PA-22-150 · Atlantic Ocean (Atlantic Ocean) · Accident · 4 fatal · Limited investigation · Final report · Aug 10, 1990 · N6946D · Destroyed
  > Undetermined. The airplane is missing.

Next page: https://openairdocs.org/ntsb-phases/990/cases.md?page=23

## The whole list in SQL

Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS:

```sql
WITH phase_names(main, name) AS (VALUES (100, 'Prior to flight'), (150, 'Standing'), (200, 'Pushback/towing'), (250, 'Taxi'), (300, 'Takeoff'), (350, 'Initial climb'), (400, 'Enroute'), (450, 'Maneuvering'), (500, 'Approach'), (550, 'Landing'), (600, 'Emergency descent'), (650, 'Uncontrolled descent'), (700, 'Post-impact'), (750, 'After landing'), (800, 'Other'), (990, 'Unknown')),
  crosswalk(code, main, name) AS (VALUES (500, 150, 'Standing'), (501, 150, 'Standing - pre-flight'), (502, 150, 'Standing - starting engine(s)'), (503, 150, 'Standing - engine(s) operating'), (504, 150, 'Standing - engine(s) not operating'), (505, 150, 'Standing - idling rotors'), (510, 250, 'Taxi'), (511, 200, 'Taxi - pushback/tow'), (512, 250, 'Taxi - to takeoff'), (513, 250, 'Taxi - from landing'), (514, 250, 'Taxi - aerial'), (520, 300, 'Takeoff'), (521, 300, 'Takeoff - roll/run'), (522, 350, 'Takeoff - initial climb'), (523, 300, 'Takeoff - aborted'), (530, 400, 'Climb'), (531, 400, 'Climb - to cruise'), (540, 400, 'Cruise'), (541, 400, 'Cruise - normal'), (542, 400, 'Maneuvering - holding (IFR)'), (550, 400, 'Descent'), (551, 400, 'Descent - normal'), (552, 600, 'Descent - emergency'), (553, 650, 'Descent - uncontrolled'), (560, 500, 'Approach'), (561, 500, 'Approach - VFR pattern - downwind'), (562, 500, 'Approach - VFR pattern - base turn'), (563, 500, 'Approach - VFR pattern - base leg/base to final'), (564, 500, 'Approach - VFR pattern - final approach'), (565, 500, 'Go-around (VFR)'), (566, 500, 'Approach - IAF to FAF/outer marker (IFR)'), (567, 500, 'Approach - FAF/outer marker to threshold (IFR)'), (568, 500, 'Circling (IFR)'), (569, 500, 'Missed approach (IFR)'), (570, 550, 'Landing'), (571, 550, 'Landing - flare/touchdown'), (572, 550, 'Landing - roll'), (573, 550, 'Landing - aborted'), (574, 550, 'Emergency landing'), (575, 550, 'Emergency landing after takeoff'), (576, 600, 'Emergency descent/landing'), (580, 450, 'Maneuvering'), (581, 450, 'Maneuvering - aerial application'), (582, 450, 'Maneuvering - turn to reverse direction'), (583, 450, 'Maneuvering - turn to landing area (emergency)'), (590, 450, 'Hover'), (591, 450, 'Hover - in ground effect'), (592, 450, 'Hover - out of ground effect'), (600, 800, 'Other'), (610, 990, 'Unknown')),
  current_codes AS (
    SELECT e.case_mkey, TRY_CAST(e."tier1Number" AS INTEGER) AS code,
      row_number() OVER (PARTITION BY e.case_mkey ORDER BY coalesce(e."isDefiningEvent", false) DESC, e.position) AS n
    FROM 'https://openairdocs.org/data/latest/ntsb_events.parquet' e
    WHERE e.aircrafts_position = 1 AND e."tier1Number" GLOB '[1-9][0-9]*'
      AND (e."isDefiningEvent" OR e.case_mkey IN (SELECT "mKey" FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' WHERE "isPre1982"))
  ),
  phases AS (
    SELECT case_mkey, 'current' AS scheme, code, CASE WHEN code >= 990 THEN 990 ELSE code // 50 * 50 END AS main
    FROM current_codes WHERE n = 1
    UNION ALL
    SELECT o.case_mkey, 'older', o."phaseOfFlightCode", w.main
    FROM 'https://openairdocs.org/data/latest/ntsb_occurrences.parquet' o JOIN crosswalk w ON w.code = o."phaseOfFlightCode"
    WHERE o.aircrafts_position = 1 AND o."occurrenceNumber" = 1 AND o.case_mkey NOT IN (SELECT case_mkey FROM current_codes)
  ),
  case_phases AS (
    SELECT p.*, c."eventDate", c."highestInjuryLevel" = 'Fatal' AS fatal, a.aircraft_model_code
    FROM phases p JOIN 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c ON c."mKey" = p.case_mkey
    LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = p.case_mkey AND a.position = 1
    WHERE c."eventDate" >= DATE '1962-01-01' AND p.main IN (SELECT main FROM phase_names)
  )
SELECT c."ntsbNumber", c."eventDate", c."eventType", c."eventCity", c."eventStateOrRegion", a.n_number, a."aircraftMake", a."aircraftModel", c."highestInjuryLevel", c."totalFatal", c."completionStatus", c.report_url
FROM 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c LEFT JOIN 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' a ON a.case_mkey = c."mKey" AND a.position = 1
WHERE c."mKey" IN (SELECT case_mkey FROM case_phases WHERE main = 990)
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb-phases/990/cases?page=22

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