# Accident 19890731026159A: Bell 206B, Rialto, CA, July 31, 1989

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: July 31, 1989, 13:35 local time
- Place: Rialto, CA
- Airport: Rialto Municipal/Miro Field Airport
- Damage: Substantial damage
- Phase of flight: Autorot Descent (Rotorcraft)
- Operating rules: General operating rules (Part 91)
- Location: 34.1007° N, 117.3794° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=34.1007&lon=-117.3794&mi=10
- Aircraft: N10857 (not matched to a registry record)
- Reported make and model: BELL 206B
- Reported engine: ALLSN 250C20B
- People aboard: 2
- Fatal injuries: 0
- Pilot flight hours: 5,600 total, 1,400 in this make and model, 80 in the last 90 days
- NTSB investigation: [NTSB LAX89LA253](https://openairdocs.org/ntsb/LAX89LA253) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19890731026159A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

DRIVESHAFT COUPLING SEPARATED FROM TRANSMISSION ON FLAIR TO HOVER AUTOROTATION. COUPLING WAS IMPROPERLY SECURED.

## The NTSB's investigation of this event (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB LAX89LA253](https://openairdocs.org/ntsb/LAX89LA253), Jul 31, 1989: Bell 206B (N10857), Rialto, CA, substantial damage. Probable cause: FAILURE TO INSTALL TWO OF THE FOUR REQUIRED NUTS WHICH RETAIN THE HIGH SPEED COUPLING INPUT DRIVE SHAFT TO THE TRANSMISSION.

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

---
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.