# NTSB ANC91LA058: Bell UH-1B, N87966, Dog Fish Bay, AK, May 21, 1991

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Limited investigation · Final report
- Date: May 21, 1991, 12:32 local (20:32 UTC)
- Place: Dog Fish Bay, AK
- Coordinates: 59.399242, -151.319076 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=59.3992&lon=-151.3191&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed, report July 13, 1993
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 5543
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC91LA058
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/5543/pdf
- Page: https://openairdocs.org/ntsb/ANC91LA058

## Probable cause

THE PILOT'S EXCEEDING THE GROSS WEIGHT OF THE AIRCRAFT AND INADEQUATE SUPERVISION BY COMPANY MANAGEMENT. CONTRIBUTING TO THE ACCIDENT WAS THE HIGH VEGETATION.

## Sequence of events

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

- Loss of control - in flight, takeoff - initial climb
  - terrain condition - high vegetation (contributing factor)
  - aircraft weight and balance - exceeded, pilot in command (cause)
  - supervision - inadequate, company/operator management (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE HELICOPTER HAD JUST LIFTED OFF WITH A LOG ON A 150 FOOT LONG LINE WHEN THE HELICOPTER CRASHED.  THE INVESTIGATION REVEALED THAT THE HELICOPTER WAS OVERWEIGHT BY 1,660 POUNDS.

## Aircraft

- Registration: [N87966](https://openairdocs.org/deregistered/N87966-2013-05-15), registration cancelled 2013-05-15, S/N 64-13968, built 1964 (OpenAirDocs)
- Reported make and model: BELL UH-1B
- Registry model: [Bell UH-1B](https://openairdocs.org/model/bell-uh-1b) (registry code 1181410) (OpenAirDocs)
- Registry engine: [Lycoming T-53 series](https://openairdocs.org/engine/lycoming-t-53-series) (registry code 41552, turbo-shaft) (OpenAirDocs)
- Category: Helicopter
- Serial number: 6413968
- Airframe hours: 3525
- Engines: LYCOMING T53-L11D 1100 horsepower turbo shaft
- Damage: Destroyed
- Fire: On-Ground
- Flight: Other work use, Part 133
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: 100 hour, May 18, 1991, 26 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 44; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; toxicology performed; flight hours: 10,965 total, 2,000 in this make and model, 10,000 as pilot in command, 55 in the last 90 days, 30 in the last 30 days, 6 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 270° at 10 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 61 °F, dew point 41 °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 19910521016719A](https://openairdocs.org/incident/19910521016719A), May 21, 1991: Bell UH1B, Dog Fish Bay, AK, Destroyed, 1 fatal. Ground crewman choker setter hooked long line to log 1600 lbs over gross. Ripped out helicopter belly causing crash

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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