# NTSB investigations: Helio H-391B

A list on [Helio H-391B](https://openairdocs.org/model/helio-h-391b.md).

Matched to the registry by N-number and event date, newest first.

- [NTSB CEN25LA325](https://openairdocs.org/ntsb/CEN25LA325.md): Helio H-391B · Monroe, MI · Accident · No injuries · Class 4 · Limited · Final report · Aug 18, 2025 · N4431U · Substantial damage
  > The pilot’s failure to maintain directional control during the landing roll with a crosswind.
- [NTSB ANC19LA027](https://openairdocs.org/ntsb/ANC19LA027.md): Helio H391 · Hope, AK · Accident · No injuries · Class 3 · Limited · Final report · Jun 12, 2019 · N10CJ · Substantial damage
  > The pilot’s failure to maintain directional control during a precautionary landing, which resulted in a ground loop. Contributing to the accident was a partial loss of engine power for reasons that could not be determined.
- [NTSB DEN02LA048](https://openairdocs.org/ntsb/DEN02LA048.md): Helio H-391B · Cheyenne, WY · Accident · No injuries · Limited investigation · Final report · May 24, 2002 · N25BA · Substantial damage
  > the pilot's failure to maintain directional control.
- [NTSB ANC01LA066](https://openairdocs.org/ntsb/ANC01LA066.md): Helio H-391B · Anvik, AK · Accident · No injuries · Limited investigation · Final report · Jun 2, 2001 · N25BA · Substantial damage
  > The pilot's continued operation of the accident airplane with known equipment deficiencies, and an improper installation of the float assembly by maintenance personnel. A factor in the accident was the pilot's delay in aborting the takeoff.
- [NTSB ATL94LA054](https://openairdocs.org/ntsb/ATL94LA054.md): Helio HE391B · Saluda, SC · Accident · No injuries · Limited investigation · Final report · Feb 26, 1994 · N9050R · Substantial damage
  > The pilot's and mechanic's failure to adequately inspect the aircraft fuel system which resulted in fuel starvation.
- [NTSB ANC94LA007](https://openairdocs.org/ntsb/ANC94LA007.md): Helio H-391-B · Beaver Creek, AK · Accident · No injuries · Limited investigation · Final report · Oct 8, 1993 · N173K · Substantial damage
  > The pilot's failure to maintain the required airspeed during the emergency descent as published in the pilot's manual. A factor is the loss of engine power for undetermined reasons.
- [NTSB SEA92LA191](https://openairdocs.org/ntsb/SEA92LA191.md): Helio H-391B · Edmonds, WA · Accident · No injuries · Limited investigation · Final report · Aug 26, 1992 · N4431U · Destroyed
  > The partial loss of engine power when an exhaust valve seized in the open position and the water where the pilot was forced to land, which resulted in an acft nose over on touchdown.
- [NTSB LAX91LA144](https://openairdocs.org/ntsb/LAX91LA144.md): Helio H391B · Prescott, AZ · Accident · No injuries · Limited investigation · Final report · Mar 23, 1991 · N289LM · Substantial damage
  > The pilot's failure to maintain directional control and improper use of the flight controls. Contributing to this accident was the cross wind and soft terrain, and the pilot's lack of experience in the airplane.
- [NTSB ANC90LA178](https://openairdocs.org/ntsb/ANC90LA178.md): Helio H-391B · Circle, AK · Accident · No injuries · Limited investigation · Final report · Sep 13, 1990 · N316HW · Substantial damage
  > Pilot-in-command's failure to maintain airplane control and the pilot's failure to identify the stall.
- [NTSB CHI90LA031](https://openairdocs.org/ntsb/CHI90LA031.md): Helio H-391B · Plainwell, MI · Accident · No injuries · Limited investigation · Final report · Nov 20, 1989 · N8750R · Substantial damage
  > Failure of the crosswind landing gear system to engage on the left main gear due to improper rigging adjustment by maintenance personnel. Factors related to the accident were: unfavorable wind conditions (gusts and quartering crosswind) and soft terrain in…
- [NTSB DEN86LA040](https://openairdocs.org/ntsb/DEN86LA040.md): Helio H-391B · Bozeman, MT · Accident · No injuries · Limited investigation · Final report · Dec 6, 1985 · N4101D · Substantial damage
  > According to personnel in the area, the plt radioed he had smoke in the cockpit and was returning to gallantin field, his departure point. Later, the plt transmitted that the eng lost total pwr and he was making a forced landing. During the investigation, it…
- [NTSB SEA84LA026](https://openairdocs.org/ntsb/SEA84LA026.md): Helio H-391B · Hood River, OR · Accident · No injuries · Limited investigation · Final report · Nov 19, 1983 · N4431U · Substantial damage
  > According to FAA inspectors, the plt made a hi speed turnoff onto a taxiway after landing & ground looped the acft. The plt stated that the right brake failed, the acft rolled off the rwy into mud & the plane spun 270 deg to the left. However, the right brake…
- [NTSB CHI83LA248](https://openairdocs.org/ntsb/CHI83LA248.md): Helio H-391B · Croton, MI · Accident · No injuries · Limited investigation · Final report · Jun 5, 1983 · N4119D · Substantial damage
  > The acft collided with wires on an approach to a lake.
- [NTSB SEA82FYE30](https://openairdocs.org/ntsb/SEA82FYE30.md): Helio H-391B · Bellingham, WA · Accident · No injuries · Closed · May 29, 1981 · N316HW · Substantial damage
- [NTSB ANC80FAA15](https://openairdocs.org/ntsb/ANC80FAA15.md): Helio Acft H-250 · Northway, AK · Accident · No injuries · Closed · Jun 28, 1980 · N173K · Substantial damage
- [NTSB ANC78DAH04](https://openairdocs.org/ntsb/ANC78DAH04.md): Helio Acft 391B · Iliamna, AK · Accident · No injuries · Closed · Jul 26, 1978 · N6023 · Substantial damage
- [NTSB NYC78FGM07](https://openairdocs.org/ntsb/NYC78FGM07.md): Helio Acft 391 · Bedford, PA · Accident · No injuries · Closed · Oct 28, 1977 · N4169D · Substantial damage
- [NTSB ANC77DAH05](https://openairdocs.org/ntsb/ANC77DAH05-201360.md): Helio Acft H-391B · Anchorage, AK · Accident · No injuries · Closed · Oct 23, 1976 · N4144D · Substantial damage
- [NTSB CHI74FEP20](https://openairdocs.org/ntsb/CHI74FEP20.md): Helio Acft H-391B · Eau Claire, WI · Accident · No injuries · Closed · Oct 17, 1973 · N8750R · Substantial damage
- [NTSB FTW73FQD12](https://openairdocs.org/ntsb/FTW73FQD12.md): Helio Acft H-391B · El Paso, TX · Accident · No injuries · Closed · Dec 30, 1972 · N316HW · Substantial damage
- [NTSB ANC73DAG34](https://openairdocs.org/ntsb/ANC73DAG34.md): Helio Acft H-391B · Chitina, AK · Accident · No injuries · Closed · Aug 9, 1972 · N74037 · Substantial damage
- [NTSB ANC71DAG83](https://openairdocs.org/ntsb/ANC71DAG83.md): Helio H391B · Anchorage, AK · Accident · No injuries · Closed · Apr 10, 1971 · N4123D · Substantial damage
- [NTSB NYC71DFA35](https://openairdocs.org/ntsb/NYC71DFA35.md): Helio Acft H-391 · Malone, NY · Accident · No injuries · Closed · Jan 3, 1971 · N4169D · Substantial damage
- [NTSB ANC71DAG19](https://openairdocs.org/ntsb/ANC71DAG19.md): Helio Acft H-391B · Ninilchik, AK · Accident · No injuries · Closed · Aug 24, 1970 · N4123D · Substantial damage
- [NTSB SEA70D0134](https://openairdocs.org/ntsb/SEA70D0134.md): Helio Acft H-391B · Reedsport, OR · Accident · No injuries · Closed · Oct 7, 1969 · N6025 · Substantial damage
- [NTSB DIA69F0128](https://openairdocs.org/ntsb/DIA69F0128.md): Helio H-391B · Cumberland, MD · Accident · No injuries · Closed · Jan 7, 1969 · N12620 · Substantial damage
- [NTSB NYC69A0008](https://openairdocs.org/ntsb/NYC69A0008.md): Helio H-391B · Royalston, MA · Accident · 2 fatal · Closed · Jul 10, 1968 · N28B · 2 aircraft · Destroyed
- [NTSB NYC69A0008](https://openairdocs.org/ntsb/NYC69A0008.md): Helio Acft H-391B · Royalston, MA · Accident · 2 fatal · Closed · Jul 10, 1968 · N28B · 2 aircraft · Destroyed
- [NTSB MIA68F0266](https://openairdocs.org/ntsb/MIA68F0266.md): Helio Acft H-391B · Lithonia, GA · Accident · No injuries · Closed · Oct 26, 1967 · N4135D · Substantial damage
- [NTSB OAK67F0166](https://openairdocs.org/ntsb/OAK67F0166.md): Helio Acft H-391B · Oakland, CA · Accident · No injuries · Closed · Nov 15, 1966 · N4109D · Substantial damage
- [NTSB NYC67F0343](https://openairdocs.org/ntsb/NYC67F0343.md): Helio H-391B · Fisher, NY · Accident · No injuries · Closed · Oct 23, 1966 · N6022 · Substantial damage
- [NTSB NYC67F0308](https://openairdocs.org/ntsb/NYC67F0308.md): Helio H-391B · Manville, NJ · Accident · No injuries · Closed · Oct 20, 1966 · N6021 · Substantial damage
- [NTSB LAX67F0059](https://openairdocs.org/ntsb/LAX67F0059.md): Helio H-391B · Van Nuys, CA · Accident · No injuries · Closed · Aug 2, 1966 · N173K · Substantial damage
- [NTSB DEN66D0315](https://openairdocs.org/ntsb/DEN66D0315.md): Helio Acft H395 · Cliff, NM · Accident · No injuries · Closed · May 15, 1966 · N4200B · Substantial damage
- [NTSB NYC66F0638](https://openairdocs.org/ntsb/NYC66F0638.md): Helio H-391 · Orangeburg, NY · Accident · No injuries · Closed · Apr 17, 1966 · N6022 · Substantial damage
- [NTSB NYC66D0232](https://openairdocs.org/ntsb/NYC66D0232.md): Helio 391B · Livingston Mnr, NY · Accident · No injuries · Closed · Sep 6, 1965 · N74037 · Substantial damage
- [NTSB SEA66A0014](https://openairdocs.org/ntsb/SEA66A0014.md): Helio Acft H-391B · Mead, WA · Accident · 1 fatal · Closed · Aug 19, 1965 · N4132D · Destroyed
- [NTSB UNK65X0217](https://openairdocs.org/ntsb/UNK65X0217.md): Helio 391B · Perry, FL · Accident · Minor injuries · Closed · Oct 10, 1964 · N173K · Substantial damage

## 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_aircrafts.parquet' a JOIN 'https://openairdocs.org/data/latest/ntsb_case_detail.parquet' c ON c."mKey" = a.case_mkey
WHERE a.aircraft_model_code IN ('4300106')
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/model/helio-h-391b/ntsb

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