# NTSB FTW86FA033: Bell 206B, N520EH, Port O'Connor, TX, January 7, 1986

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Field investigation · Final report
- Date: January 7, 1986, 16:35 local (22:35 UTC)
- Place: Port O'Connor, TX
- Coordinates: 28.410459, -96.710334 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=28.4105&lon=-96.7103&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 21885
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW86FA033
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/21885/pdf
- Page: https://openairdocs.org/ntsb/FTW86FA033

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Airframe/component/system failure/malfunction, takeoff
  - rotor drive system,tail rotor drive shaft - separation (cause)
  - reason for occurrence undetermined (cause)
- Loss of control - in flight, hover
- In flight collision with object, descent - uncontrolled
  - object - aircraft parked/standing
- In flight collision with terrain/water, descent - uncontrolled
  - terrain condition - dirt bank/rising embankment

## Analysis

THE HELICOPTER SUSTAINED A LOSS OF TAILROTOR DRIVE ON LIFT OFF. A BONDING IN A SHAFT COUPLING FAILED. EXTENSIVE RESEARCH AND ANALYSIS DISCOVERED NO DISCREPANCIES IN DESIGN, PRODUCTION, QUALITY ASSURANCE, MAINTENANCE OR OPERATING ENVIRONMENT THAT COULD HAVE RESULTED IN THIS FAILURE. ONLY ONE PREVIOUS OCCURRENCE WAS DOCUMENTED, IN AN ASSEMBLY FROM ANOTHER VENDOR.

## Aircraft

- Registration: [N520EH](https://openairdocs.org/deregistered/N520EH-1990-03-01), registration cancelled 1990-03-01, S/N 3020 (OpenAirDocs)
- Reported make and model: BELL 206B
- Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (OpenAirDocs)
- Category: Helicopter
- Serial number: 3020
- Airframe hours: 4594
- Engines: ALLISON 250-C20B 420 horsepower turbo shaft
- Damage: Destroyed
- Flight: Positioning, Part 91
- Registered owner: Era Helicopters Inc.
- Airworthiness certificate: Standard, Normal
- Last inspection: AAIP, January 3, 1986, 9 hours before
- Destination: OFFSHORE RIG, GM
- Flight plan: Company VFR
- Airport: 2TA5, Era Heliport

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 40; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: helicopter; medical: class 1, valid medical--no waivers/lim.; seat: right; flight hours: 2,136 total, 603 in this make and model, 1,751 as pilot in command, 204 in the last 90 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 340° at 20 knots, gusting 5
- Visibility: 5 statute miles
- Lowest ceiling: 600 ft overcast
- Temperature: 75 °F

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19860107000309A](https://openairdocs.org/incident/19860107000309A), Jan 7, 1986: Bell 206B, Port Oconnor, TX, Destroyed. Pilot lost control of helicopter in hover. Struck N374EH before rolling over. Tail rotor drive shaft separated.

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.

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