# NTSB ANC90LA056: Bell 206B, N1086Z, Drift River, AK, April 14, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: April 14, 1990, 09:30 local (17:30 UTC)
- Place: Drift River, AK
- Location: 60.5917° N, 152.1611° W: Placed by OpenAirDocs: center of Drift River, AK, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=60.5917&lon=-152.1611&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report March 5, 1993
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5352
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC90LA056
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5352/pdf
- Page: https://openairdocs.org/ntsb/ANC90LA056

## Probable cause

THE PILOT FAILED TO MAINTAIN CONTROL OF THE HELICOPTER DURING LIFT-OFF.

## Sequence of events

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

- Loss of control - on ground/water, takeoff
  - aircraft control - not maintained, pilot in command (cause)
- Roll over, takeoff

## Analysis

THE PILOT WAS CHECKING THE WATER DEPTH IN A RIVER. JUST AFTER LIFT-OFF FROM A AREA WITH A MILD CURRENT, THE HELICOPTER ROLLED OVER ON TO ITS RIGHT SIDE. IT WAS SUBSTANTIALLY DAMAGED AND THE PILOT AND PASSENGER WERE NOT INJURED.

## Aircraft

- Registration: N1086Z (not matched to a registry record)
- Reported make and model: BELL 206B
- Category: Helicopter
- Serial number: 2989
- Airframe hours: 5230
- Engines: ALLISON 250-C20 420 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Part 135
- Registered owner: Alaska Helicopter, Inc.
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, March 19, 1990, 22 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 33; commercial; airplane ratings: single-engine land; instrument ratings: helicopter, airplane; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 4,896 total, 1,719 in this make and model, 4,724 as pilot in command, 69 in the last 90 days, 23 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 90 statute miles
- Lowest ceiling: none
- Temperature: 39 °F, dew point 25 °F
- Altimeter: 30.00 inHg

## 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 19900414008799A](https://openairdocs.org/incident/19900414008799A), Apr 14, 1990: Bell 206B, Drift River, AK, Substantial damage. Turned float equipped helicopter sideways to River current prior to liftoff. Helicopter rolled over on its side.

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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