# NTSB investigations: Lycoming IO-540 series, 1991

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.

## Latest cases

- [NTSB LAX92LA074](https://openairdocs.org/ntsb/LAX92LA074.md): Piper PA32RT-300 · Big Bear City, CA · Accident · Minor injuries · Limited investigation · Final report · Dec 31, 1991 · N39459 · Substantial damage
  > The failure of the pilot to maintain directional control and improper use of the rudder. Contributing to the accident was the improper installation by the company of a hand control mechanism that required the pilot to operate the airplane controls with one…
- [NTSB MIA91LA221](https://openairdocs.org/ntsb/MIA91LA221.md): John H. Logan Loganair I · Gainesville, FL · Accident · 2 fatal · Limited investigation · Final report · Sep 21, 1991 · N931JL · Destroyed
  > The non-instrument rated pilot in command's decision to depart under special visual flight rule clearance in instrument flight rules conditions during darkness with a failed vacuum pump and resulting inoperative flight instruments which resulted in an…
- [NTSB CHI91DTK05](https://openairdocs.org/ntsb/CHI91DTK05.md): Eagle DW1 · Hurley, SD · Accident · No injuries · Final report · Sep 10, 1991 · N8814L · Substantial damage
  > The failure of the pilot to maintain a visual lookout.
- [NTSB ATL91LA169](https://openairdocs.org/ntsb/ATL91LA169.md): Bates, Frank L Skybolt · Yatesville, GA · Accident · Minor injuries · Limited investigation · Final report · Sep 2, 1991 · N9FB · Destroyed
  > The pilot's failure to maintain a proper altitude during maneuvering flight.
- [NTSB ANC91LA135](https://openairdocs.org/ntsb/ANC91LA135.md): Maule M-7-235 · Mystic Pass, AK · Accident · No injuries · Limited investigation · Final report · Aug 25, 1991 · N5657A · Substantial damage
  > The pilot lost control of the airplane. Contributing to the accident was unfavorable wind and turbulence.
- [NTSB BFO91LA063](https://openairdocs.org/ntsb/BFO91LA063.md): Piper PA-23-250 · New Market, VA · Accident · Serious injuries · Limited investigation · Final report · Jul 4, 1991 · N63817 · Destroyed
  > The pilot's inadequate inflight decision that resulted in VFR flight into IMC.
- [NTSB CHI91DER09](https://openairdocs.org/ntsb/CHI91DER09.md): Eagle Eagle DW-1 · Windom, MN · Accident · No injuries · Final report · Jun 28, 1991 · N88142 · Substantial damage
  > The pilot's improper aircraft handling. Related factors are the pilot's inattention and the airplane's deteriorated performance capability.
- [NTSB CHI91DCQ06](https://openairdocs.org/ntsb/CHI91DCQ06.md): Piper PA-36-300 · Oakley, KS · Accident · No injuries · Final report · Jun 13, 1991 · N59661 · Substantial damage
  > A loss of engine power for an undetermined reason(s).
- [NTSB FTW91DRA03](https://openairdocs.org/ntsb/FTW91DRA03.md): Bronner Skybolt · Alvin, TX · Accident · No injuries · Final report · Jun 8, 1991 · N773HD · Substantial damage
  > The pilot's failure to maintain terrain clearance. A factor was the pilot's decision to perform a low pass.
- [NTSB CHI91DER04](https://openairdocs.org/ntsb/CHI91DER04.md): Bellanca Eagle DW-1 · Hector, MN · Accident · No injuries · Final report · Jun 6, 1991 · N8800W · Substantial damage
  > The loss of engine power due to the total failure of a connecting rod. Related factors are the low maneuvering altitude and the unsuitable (muddy) terrain encountered during the forced landing.
- [NTSB NYC91FA145](https://openairdocs.org/ntsb/NYC91FA145.md): Piper PA-32RT-300 · Wallingford, CT · Accident · 1 fatal · Field investigation · Final report · May 31, 1991 · N36069 · Destroyed
  > The pilot attempting a VFR flight in adverse weather conditions, at an altitude that was insufficient to clear trees along his route of flight. Factors related to the accident were the pilot's lack of instrument rating, and his overconfidence to fly in…
- [NTSB ANC91IA052](https://openairdocs.org/ntsb/ANC91IA052.md): Piper PA-32-301 · Eek, AK · Incident · No injuries · Incident investigation · Final report · Apr 9, 1991 · N4258N · Minor damage
  > The failure of the center torque link bolt.
- [NTSB NYC91LA065](https://openairdocs.org/ntsb/NYC91LA065.md): Piper PA-32-301 · Celina, OH · Accident · No injuries · Limited investigation · Final report · Jan 24, 1991 · N8385S · Substantial damage
  > The pilot-in-command's improper use of the powerplant controls, magnetos and brakes.
- [NTSB FTW91LA032](https://openairdocs.org/ntsb/FTW91LA032.md): Piper PA-32R-301 · Enid, OK · Accident · No injuries · Limited investigation · Final report · Jan 23, 1991 · N82162 · Substantial damage
  > The mechanical failure of the ignition switch. A factor was the pilot's failure to apply the parking brake or use airplane wheel chocks.

## The whole list in SQL

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

```sql
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 year(c."eventDate") = 1991
  AND c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41530', '41585'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41530&year=1991

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OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.