# NTSB investigations: Lycoming GO-435C&D series, MT

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 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 SEA68D0218](https://openairdocs.org/ntsb/SEA68D0218.md): Aero Comdr 520 · Bozeman, MT · Accident · No injuries · Closed · Nov 22, 1967 · N2625B · 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_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."eventStateOrRegion" = 'MT' AND c."eventCountry" = 'USA'
  AND c."mKey" IN (SELECT x.case_mkey FROM 'https://openairdocs.org/data/latest/ntsb_aircrafts.parquet' x WHERE x.engine_model_code IN ('41521'))
ORDER BY c."eventDate" DESC, c."ntsbNumber" DESC
```

This list as a web page: https://openairdocs.org/ntsb?engine=41521&state=MT

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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.